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RECYCLING AND RE-USING OUTDATED PRE-PREG CARBON FIBER COMPOSITES FOR SOCCER SHIN-GUARD FABRICATIONS A Project by Yashwanth reddy bathula Bachelor of Technology, JNT University,2014 Submitted to the Department of Mechanical Engineering and the faculty of the Graduate School of Wichita State University inpartial fulfillment of the requirements for the degree of Master of Science May 2016

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Copyright 2016 by Yashwanth Reddy Bathula All Rights Reserved

PROJECT USING OUTDATED PRE-PREG CARBON AND GLASS FIBER COMPOSITES FOR SOCCER SHIN-GUARD FABRICATIONS The following faculty members have examined the final copy of this thesis for form and content, and recommend that it be accepted in partial fulfillment of the requirement for the degree of Master of Science with a major in Mechanical Engineering. _____________________________ Ramazan Asmatulu, Committee Chair _____________________________ Yimesker Yihun, Committee Member

ACKNOWLEDGEMENTI extend my heartfelt gratitude to my advisor Dr. Ramazan Asmatulu, for providing me an opportunity to work on a project under him. His brilliant idea and guidance through the years have helped me progress in my work efficiently. I am grateful to my committee member, Dr. Yimesker Yihun, who shared his knowledge and essential comments during various stages of this project work. I am thankful to the entire faculty and staff of Department of Mechanical Engineering, WSU, for being so helpful at all the times. I extend my vote of thanks to NIAR-WSU for letting me use their machines for the completion of project. I am gratified towards my lab mates, Praveen Kumar Bolavaram and Abhijeet Singamaneni for their assistance while I was working in the lab. I appreciate Vamsi Patlolla for his keen interest in my work and for their valuable efforts in completing my project.Lastly, I am greatly indebted to my family and friends for having immense faith in me and motivating me to keep moving forward.

ABSTRACTCarbon fiber is extensively used in shin guard materials and structures. The purpose of this research was to improve the impact resistance of the soccer shin guards which are made of outdated pre-preg carbon fiber composites. The composites are needed to be tested for impact damages for the designing and manufacturing of shin guards which determines the reduction of any damage to human leg tissues. The specimens were fabricated and cured under a vacuum and high temperature for the pre-preg, carbon fibers, namely unidirectional fiber, plain weave woven fiber. Carbon panels consisting 16 plies each underwent impact test using a low velocity impactor and visual damage inspection by C-scan to measure the damage area and depth of indentation. These composite panels were impacted with standard tup diameter and energy levels. The impact damages were dependent on the type of composite structure which may be critical for the design, manufacture of shin guard composites. These results may be helpful in improving the capacity of the carbon fiber with cost reduction and growing new markets thus making a carbon fiber more viable commercial product.Ultra-sonic C-scan tests were performed on the specimen to check any delamination and voids present in the specimen.

TABLE OF CONTENTSCHAPTER PAGE INTRODUCTION101.1 Motivation101.2 Background101.2.1Application to Sports101.2.2Introduction to football11CHAPTER II13LITERATURE REVIEW132.1Composite132.1.1Types of Composites142.1.2Manufacturing of composites162.2Fiber182.3MATRIX212.4Pre-pregs222.5Vacuum Bag Materials23CHAPTER III27EXPERIMENTAL273.1Test Procedure273.2Mold Preparation273.3Cutting and Lay up273.4Debulk Procedure303.5Bagging Procedure313.6Cure cycle333.7Bag Removal and Part Identification34CHAPTER-435RESULTS AND DISCUSSIONS354.1RESULTS354.1.1Before Impact C- Scan Images364.1.2Impact Analysis374.1.3 After Impact C- Scan Images384.1.4Graphical Modelling39CHAPTER-542CONCLUSION42CHAPTER-643FUTURE WORK43REFERENCES46

List of FiguresFigures Page1. Composite Laminate Specimen142. Continuous and Discontinuous Composites153. showing the plies of 0 and 45 plies164. Classes of Composites165. Matrix in a Fiber226. Tape and fabric reinforcements237. Vacuum Bagging Materials238. Peel Ply259. Application of Lay up tape on the specimen2510. Perforated Release Film2611. Solid Release Film2612. Breether Material2713. Vacuum Bagging Set up2814. Test Valve2815. Apparatus for the drop Wise test29Figure 16: Test fixtures for the experimental study32Figure 17: Impactor used for the experimental study32Figure 18: Figure: Ultra Sonic C Scan Tank34Figure 19: Carbon fiber panel with required orientation36Figure 20 Unidirectional Carbon Fiber Panel36Figure 21: Woven Fabric Panel with The Required Orientation37Figure 22: Layup Orientation37Figure 23: Laminate Layup (Vacuum Bag and Port Not Shown for Clarity).38Figure 24:Carbon fiber panel after applying silicone rubber adhesively and the plates on which the panel is to be placed.39Figure 25: After Bagging41Figure 26: Cure Cycles Information42Figure 27: Oven42Figure 28 : C scan Image before Impact of Uni directional carbon Fiber45Figure 29 : C- Scan Image before Impact of Woven fiber45Figure 30: After Impact 2-1A46Figure 31 :After Impact 2-2 A47Figure 32: Woven Fiber With silicone Rubber 3-1A47Figure 33 :Woven fiber with silicone rubber 3-2 A47Figure 34: Graph Energy v/s Time48Figure 35: Graph Load v/s Time48Figure 36:Graph Load vs Deflection49Figure 37: Load vs time49Figure 38: Time vs Energy50Figure 39: Load vs Deflection50Figure 40 : Figure Energy Vs time51Figure 41: Load vs Time51Figure 42: Figure Load vs Time52

List of TablesTable 1: Table: Dent Depths of specimens47

List of Abbreviations AS Asymmetric CF Carbon Fiber CFRP Carbon Fiber-reinforced Polymer FRP Fiber-Reinforced Polymer GFRP Glass Fiber-Reinforced Polymer GPa Giga Pascal J Joule PW Plain Weave RFI Resin Transfer Mold UD Unidirectional Pre-preg TapeWt.% Weight Percentage

CHAPTER 1INTRODUCTION

1.1 Motivation Even though the manufacturers take a lot of care while manufacturing the soccer shin guards which protect the athletes from getting injured. But the impact caused by the force could be such that the damage is huge. The depth until which the fiber composite can be resistible from getting damaged.1.2 BackgroundWhat we now refer to as shin guards look to have originated from protective armor that was used in various types of battles throughout history known as a greave in ancient times, the armor was often made from bronze and would cover a large area of the lower leg. Although they appeared in pictures beforehand, the earliest physical evidence of theguards in this form were when archaeologist Sir William Temple discovered a pair of bronze greaves with a Gorgons head design in the relief on each knee capsule. It was later estimated that the greaves were madein Southern Italy, around 550/500 B.C.E. So, the earliest discovered shin guards were custom shin guards.1.2.1Application to SportsFast forward into the 19th century and, inspired by their use in battle, various sports began to adopt the use of shin guards. Cricket batsmen however were less concerned with protection and more with using their oversized pads to block the stumps, an advantage that was later outlawed by the leg before wicket rule change. Other sports to adopt the use of shin protection include hiking, mixed martial arts, kickboxing and other combat sports.1.2.2Introduction to footballAs far as football is concerned, 1874 is the year shin guards are believed to have been introduced to the game by Sam Weller Widdowson. A cricketer for Nottinghamshire and footballer for Nottingham Forest, Widdowson strapped an altered pair of cricket pads outside his football socks and the first shin guards were born. Despite being initially ridiculed, his idea caught on and the equipment became commonplace. Eventually players grew frustrated with the burden of extra weight under their socks and began to play without shin guards again, however FIFA regulations were later introduced making them compulsory A composite is a mix of two or more materials with various properties to frame a material framework with properties superior to the individual guardian materials. Composite materials discover their applications in different commercial enterprises because of their fabulous mechanical and other physical properties. They have been in presence since the 1940s, and have grown altogether from that point forward. Glass fiber is the most regularly utilized composite material. Different fiber materials have been delivered throughout the years, and carbon filaments at first created in the 1960s have been widely used for the essential flying machine structures. As the filaments have high solidness and quality, the greater part of the fortifications utilized as a part of assembling a composite overlay are in stringy structures. As a result of their high angle proportion, load connected to the strands can be exchanged through a generally powerless lattice material without impelling the network disappointment. As these strands have little distances across, they are very adaptable which makes it conceivable to embrace different strategies to fabricate composite overlays. Carbon filaments installed in an epoxy lattice are progressively utilized for essential airplane applications in view of their long exhaustion life, erosion resistance, and high quality to thickness proportion and high solidness to thickness proportion.

CHAPTER 2LITERATURE REVIEW 2.1Composite A composite material is made out of two or materials of fundamentally unique material properties that together shape a material better than the child rearing materials (1). A composite material is proposed for better mechanical, warm, or electrical properties and can be modified for appropriate applications. Composites can be fabricated to be lighter, more grounded, and vigorous than the individual guardian materials.Few every now and again utilized composites are solid, where baggy stones are varying in concrete, and plywood, in which wood is amassed at various introductions (fiber bearings) to make the whole material more grounded [1]. Another procedure, and at present the most examined and inquired about, is fiber-strengthened polymers (FRPs). A FRP can be readied utilizing carbon fiber-strengthened polymer (CFRP) or glass fiber-fortified polymer (GFRP). There are reasons and points of interest for utilizing FRPs [2]. The fundamental advantage of utilizing a FRP is that the composite material can be effectively adjusted to meet the separate application necessities while holding the favored mechanical, warm, or flexible properties. Carbon fiber is another type of high quality material. Late patterns and gauges of carbon fiber utilization have strikingly duplicated. Cutting edge light-weight materials, for example, carbon fiber composites, could diminish traveler auto weight by 50 percent and enhance fuel effectiveness by around 35 percent without bargaining execution or wellbeing. In late decades, carbon strands have discovered broad applications in business shin protectors and modern markets, in light of the fact that the cost of carbon fiber has diminished and innovations have progressed. The business sector for carbon fiber has encountered great development as of late with the exception of 2009 because of retreat in different parts of the world and monetary turmoil. The development rate throughout the previous 23 years was around 10%. In case of making composites, two boss parts included: fiber and network. The lattice, or the epoxy, for polymers is arranged into two sorts: thermosets and thermoplastics, each having their own particular advantages and disadvantages, however all the more imperatively, they can be utilized and directed for a specific application, or they can be an inclination for use with a fiber to design the important composite. Figure 1 shows an illustration of a composite laminate.

Figure 1: Composite Laminate Specimen2.1.1Types of CompositesComposite materials are commonly classified at following two distinct levels: The first level of classification is usually made with respect to the matrix constituent. The major composite classes include Organic Matrix Composites (OMCs), Metal Matrix composites (MMCs) and Ceramic Matrix Composites (CMCs). The term organic matrix composite is generally assumed to include two classes of composites, namely Polymer Matrix Composites (PMCs) and carbon matrix composites commonly referred to as carbon composites [3]. The second level of classification refers to the reinforcement form - fiber reinforced composites, laminar composites and particulate composites. Fiber Reinforced composites (FRP) can be further divided into those containing discontinuous or continuous fibers. Fiber Reinforced Composites are composed of fibers embedded in matrix material. Such a composite is considered to be a discontinuous fiber or short fiber composite if its properties vary with fiber length. On the other hand, when the length of the fiber is such that any further increase in length does not further increase, the elastic modulus of the composite, the Composite is considered to be continuous fiber reinforced. Fibers are small in diameter and when pushed axially, they bend easily although they have very good tensile properties. These fibers must be supported to keep individual fibers from bending and buckling. Laminar Composites are composed of layers of materials held together by matrix. Sandwich structures fall under this category. Particulate Composites are composed of particles distributed or embedded in a matrix body.The particles may be flakes or in powder form. Concrete and wood particle boards are examples of this category [3]. Figure 2 shows the different types of composites. Figure 3 and 4 shows the plies of 0 and 45 and the different classes of composites.

Figure 2: Continuous and Discontinuous Composites

Figure 3 :showing the plies of 0 and 45 plies

Figure 4: Classes of CompositesRelation between the classes of engineering materials showing the evolution of composites1. Polymer-matrix compositesThe extensive variety of procedures used to create reinforced plastics is somewhat new, and incompletely determined established methods of processing ordinary polymeric materials. The way of combining fibers and matrix into composite materials depends very much on the particular combination and the geometry of the structured to be manufactured.The common varieties of thermoplastic-based materials, like glass-filled Nylon and glass-filled polyacetal, are made largely by the injection moulding of granules of material in which the chopped fibers and matrix have been pre-compounded [4]. The principal problem in such cases is that the flow of material during moulding may be non-uniform, especially in moulds of complex geometry. There may be regions in which the fibers are highly oriented and others where the degree of orientation is almost nil, as well as variations in fiber content from place to place.2.Metal-matrix compositesThe fundamental traits of metals fortified with hard clay particles or strands are enhanced quality furthermore, solidness, enhanced crawl and weakness resistance, and expanded hardness, wear and scraped spot resistance, joined with the likelihood of higher working temperatures than for the unreinforced metal (or contending fortified plastics). These properties offer potential for abuse in a scope of pump and motor applications, including compressor bodies, vanes and rotors, cylinder sleeves and supplements, associating bars, et cetera. Parts of this write are still a work in progress, yet few are in business creation (Feest, 1986) aside from maybe a couple constrained applications in Japanese vehicles. Hence, despite the fact that an extensive variety of assembling strategies has been utilized in the course of the last twenty a long time on a lab or improvement scale, at this stage moderately little can be said in regards to extensive scale creation forms for MMCs.3.Ceramic-matrix compositesCreation procedures are mind boggling and should be painstakingly advanced as a result of the unavoidable affectability of materials properties to microstructures controlled by preparing conditions and cooperations. A great part of the late work on CMCs in the US, Japan and Europe has to a great extent took after generally well known courses in endeavoring to strengthen glasses (like borosilicate) and glass-pottery (like lithium aluminosilicate or LAS and calcium aluminosilicate or CAS) with strands, for example, the business Nicalon and Tyranno assortments of silicon carbide [4]. Significant enhancements in mechanical properties have been accomplished, by correlation with early carbon-fiber/glass composites. The strands are for the most part impregnated with slurry of fine glass powder and in this way hot-squeezed (Dawson et al, 1987). In the event that the grid is a glass-fired, the last stage in production is the "ceramming" process, the last warmth medicines to change over the glass to a completely thick fired. Organizations like Corning in the US offer such materials for business deal. Basic control of assembling conditions is expected to create proper interfacial conditions for the ideal mix of quality and sturdiness. The point of preference of the glass-fired course is that generally unobtrusive preparing temperatures are included.4. Hybrid compositesReference to cross breed composites most every now and again identifies with the sorts of fiber-fortified materials, typically gum based, in which two sorts of filaments are consolidated into a solitary framework. The idea is a basic expansion of the composites rule of consolidating two or more materials in order to advance their worth to the designer, allowing the misuse of their better qualities while diminishing the impacts of their less alluring properties. All things considered, the definition is significantly more prohibitive than the truth. Any mix of divergent materials could actually be considered as a half breed. An exemplary case is the sort of auxiliary material in which a metal or paper honeycomb or an unbending plastic froth is attached to thin skins of some superior FRPs, the skins conveying the high surface ductile and compressive burdens and the center giving lightweight (and modest) basic security. The mix of sheets of aluminum amalgam with overlays of fiber-fortified gum, as in the business item ARALL (aramid-strengthened aluminum, Davis, 1985) is a related assortment of layered half and half, and the blending of stringy and particulate fillers in a solitary sap or metal grid delivers another types of half and half composite [5].2.2FiberThe fortifying fixing material in a composite is the fiber, which mostly helps the heap through the composite overlay. The fiber keeps up the inflexibility of the composite while obstructing split or harms engendering. Carbon filaments are on very basic level slim strands of carbon, thinner than human hair, which can be curved on the whole, similar to yarn. The yarns can be woven together, similar to material. To make carbon fiber tackle a changeless shape, it can be laid over a mold and after that solidified with a firm sap or plastic.Advantages of carbon strands utilized as a part of industry are as per the following: Advantages Very lightweight. Durable and safe. Five times as solid as steel, and lighter and more grounded than glass. Two times as firm as glass fiber, with high modulus and high strength.DisadvantagesWaste transfer.Low recyclability.Cost can fluctuate and difficult to reuse. Anisotropic properties. Matrix degrades. Low reusability.Time devouring to make. A unidirectional (UD) fiber is one in which the greater part of strands to keep running in one course as it were. A little amount of fiber or other material may keep running in different bearings with the fundamental aim being to hold the prime filaments in position. Unidirectional filaments regularly have their pivotal strands in the 0 heading (a twist UD) yet can likewise have them at 90 degree to the move length (a weft UD). UD strands are straight and non-pleated. For mechanical properties, unidirectional fiber must be improved on by pre-preg unidirectional tape, where there is no mediocre material at all holding the unidirectional filaments set up. A unidirectional pre-preg is appeared in the figure. Plain weave carbon fiber is by and large utilized for deficient streamlined parts. It wets out rapidly and handles effectively. A plain weave is characterizes as a 1X1 weave, meaning the weave is based on an example of one fiber more than, one fiber under, and so forth there is basically no refinement in the quality of the fabric taking into account its weave. Inclination of weave relies on upon the feel, bend and weight of the fiber considered important for the application. For every fiber twisting over or under another, its quality can be traded off to some degree. A plain weave, or 1X1 weave, is the most impenetrable weave. Since the weave is unbending, it is the in all likelihood not to shred at the finishes. A case of a plain weave composite is appeared in the figure. The strength and stiffness of a composite development depends on the orientation sequence of the plies. The extent of strength and stiffness of carbon fiber reaches out from qualities as low as those by fiberglass to as high as those given by titanium. This range of the qualities is determined by the orientation of plies to the applied load. Appropriate determination of employ introduction in cutting edge composite materials is important to give a fundamentally productive outline. The part may require 0 utilizes to respond to pivotal burdens, 45 handles to respond to shear loads, and 90 employs to respond to side burdens. Since the quality outline necessities are an element of the connected burden course, handle introduction and employ succession must be right. It is basic amid a repair to supplant each harmed employ with a utilize of the same material and handle introduction. The strands in a unidirectional material keep running in one heading what's more, the quality and firmness is just toward the fiber. Pre-impregnated (pre-preg) tape is a case of a unidirectional utilize introduction. The filaments in a bidirectional material keep running in two bearings, regularly 90 separated. A plain weave fabric is a case of a bidirectional utilize introduction. These employ introductions have quality in both headings yet not as a matter of course the same quality.The utilizes of a semi isotropic layup are stacked in a 0, 45, 45, and 90 succession or in a 0, 60, and 60 grouping. These sorts of utilize introduction recreate the properties of an isotropic material. Numerous aviation composite structures are made of semi isotropic materials.2.3MatrixInterfaces are in the midst of the huge and minimum discussed parts of a composite material. The framework plays a noteworthy assignment in a composite for the accompanying reasons: Holds the fortifications in the favored introduction. Serves6 as the middle person for transmission of burden inside the fiber. Shields filaments from dangerous ecological impacts like dampness and erosion. The decision of framework as indicated by the application prerequisites can fluctuate among clay, metal, and polymer. The most ordinarily utilized grid nowadays is a polymer tar, for example, Epon 828. Frameworks can be arranged into thermosets and thermoplastics. Figure 5 shows a matrix in a fiber material Thermosetting gum is a petrochemical that ways out in a supple strong or shabby state and afterward changes irreversibly into an infusible, insoluble polymer system by curing, which energizes polymer chain cross-connecting. Curing can be instigated utilizing warm or proper radiation, or both. A cured thermosetting tar is known as a thermoset, for example, epoxy, phenolic, bismaleimide, and fluoropolymers. Thermoplastic pitch is a polymer that changes into a fluid when warmed, and stops to a shiny condition when left to cool enough.

Figure 5:Matrix in a Fiber2.4Pre-pregsPre-preg material comprises of a combination of a matrix and fiber reinforcement. It is accessible in unidirectional structure (single reinforcement direction) and fabric form (different directions of reinforcement). Each of the five of the real groups of matrix resins can be utilized to impregnate different fiber forms. The resin is then no more in a low-viscosity stage, however has been progressed to a B stage level of cure for better handling characteristics. Some of the products available in prepreg form: unidirectional tapes, woven fabrics, continuous strand rovings, and chopped mat. Prepreg materials must be put in freezer at a temperature underneath 0 F to impede the curing process. Figure 6 shows different tape and fabric reinforcements in prepregs. Prepreg materials are cured with an increase in temperature. Numerous prepreg materials utilized as a part of aviation are impregnated with an epoxy sap and they are cured at either 250 F or 350 F. Prepreg materials are cured with an autoclave, stove, or warmth cover. They are regularly purchased and stored on a roll in a sealed plastic bag to avoid moisture contamination.

Figure 6: Tape and fabric reinforcements3.1.11ASTM Test Standard used and Terminology D 7137/D 7137M Test Method for Compressive Residual Strength Properties of Damaged Polymer Matrix Composite PlateDent Depth, d [L], nresidual depth of the depression formed by an impactor after the impact event. The dent depth shall be dened as the maximum distance in a direction normal to the face of the specimen from the lowest point in the dent to the plane of the impacted surface that is undisturbed by the dent.A = cross-sectional area of a specimen CE = specied ratio of impact energy to specimen thickness CV = coefficient of variation statistic of a sample population for a given property (in percent) D = damage diameter d = dent depth E = potential energy of impactor prior to drop E1 = absorbed energy at the time at which force versus time curve has a discontinuity in force or slope Ea. = energy absorbed by the specimen during the impact event Ei = actual impact energy (incident kinetic energy) Emax = absorbed energy at the time of maximum recorded contact force F = recorded contact force F1 = recorded contact force at which the force versus time curve has a discontinuity in force or slope Fmax = maximum recorded contact force g = acceleration due to gravity h = specimen thickness H = impactor drop height l = specimen length m = impactor mass md = impactor mass for drop height calculation mdlbm = impactor mass in standard gravity for drop height calculation n = number of specimens per sample population N = number of plies in laminate under test Sn-1 = standard deviation statistic of a sample population for a given property t = time during impactor drop and impact event ti = time of initial contact tT = contact duration (total duration of the impact event) w = specimen width v = impactor velocity vi = impactor velocity at time of initial contact, ti W12 = distance between leading edges of the two ag prongs on velocity indicator xi = test result for an individual specimen from the sample population for a given propertyx = mean or average (estimate of mean) of a sample population for a given property = impactor displacementThe performance of laminated plate specimen is dependent upon many factors, such as laminate thickness, ply thickness, stacking sequence, environment, geometry, impactor mass, striker tip geometry, impact velocity, impact energy, and boundary conditions to an out-of-plane drop-weight test. Comparisons cannot be made between materials unless identical test configurations, test conditions, and laminate configurations are used. Therefore, all deviations from the standard test configuration can be put into results.Anthony C. Francisco et.al explains that the objective of this study was to assess the adequacy of various shin protectors in securing against tibia break in soccer players. An optional reason for existing was to decide the relationship between the material and basic contrasts in shin protector outline and the assurance gave. Twenty-three industrially accessible shin protectors were tried on a model leg containing a manufactured tibia that had been adjusted against human dead body examples. Every guard was ordered into one of four material sorts: plastic (N 5 9), fiberglass (N 5 6), compacted air (N 5 4), and Kevlar (N 5 4). The most extreme joined power at the finishes of the tibia, the essential strain on the back side of the tibia, and the contact time of the effect were measured utilizing a drop track sway recreation. Shin protectors gave huge insurance from tibia crack at all drop statures. The normal gatekeeper diminished power by 11% to 17% and strain by 45% to 51% contrasted and the unguarded leg. At the higher drop statures, material synthesis and auxiliary qualities of the shin protectors demonstrated noteworthy contrasts in defensive capacities. These discoveries demonstrate that all shin protectors give some measure of assurance against tibia break, in spite of the fact that the level of insurance may fluctuate altogether among the distinctive guards.Bir CA et.al explains that Worldwide > 40 million amateurs participate in the team sport of soccer. With 647,368 injuries occurring from 1989 through 1992, the risk of injury during the play of soccer is evident. Lower extremity injuries have been found to comprise 13.1% of the total injuries in soccer. To date, a comprehensive evaluation of protective equipment utilized to prevent lower extremity injuries in soccer has been lacking. This study utilized a 5th percentile Hybrid III female dummy to evaluate the effectiveness of shin guards in attenuating the forces which can lead to lower extremity injuries. A pendulum impact apparatus simulated one player being kicked by another. Impacts were delivered to the anterior tibia region of the Hybrid III dummy and peak loads were recorded. Load forces were reduced 41.2-77.1% with the utilization of shin guards. Even at extreme temperatures, the guards were found to be effective in lowering the amount of impact force transferred to the shin region. The results of this study indicate that the use of shin guards will attenuate the force of impact to the tibia and thus reduce the risk of injury.Urho M Kujala et al, based on the defined injury profiles in the differentsports it is recommended that sports specific preventive measuresshould be employed to decrease the number of violent contactsbetween athletes, including improved game rules supported bycareful refereeing. To prevent dental injuries, the wearing ofmouth guards should be encouraged, especially in ice hockey,karate, and basketball.Sjoblom, P. O et al A method for predicting impact-induced delamination in composite laminates was proposed. This method is suitable for low velocity impact with heavy impactors. Static delamination fracture toughness was used to predict delamination crack growth under impact conditions. Curing stresses were also considered and found to play a significant role in evaluating the fracture toughness of some laminates such as [905/05/905]. Experiments were performed to obtain the impact force history from which the peak force was used to determine the extent of delamination crack length. The prediction of delamination size using static fracture toughness was found to agree very well with the experimental result.J.A.M. Ferreira et.al Composite materials have been widely used in several engineering applications. However, there are very few studies about the effects of Nano clays on the impact strength of laminates after exposure to the fire. Therefore, this paper intends to study this subject and the impact performance was analyzed by low velocity impact tests carried out at different incident impact energy levels. For better dispersion and interface adhesion matrix/clay, Nano clays were previously subjected to a silane treatment appropriate to the epoxy resin. The exposure to the fire decreases the maximum load and increases the displacement in comparison with the respective values obtained at room temperature. Mathematical relationships are proposed to estimate the maximum impact force and displacement, based on the total impact energy and flexural stiffness. Finally, a decrease of the elastic recuperation can be found, independently of the benefits introduced by the Nano clays.Kalla, D.K., Zhang et. al Fiber reinforced composites have been utilized for a number of different applications, including aircraft, wind turbine, automobile, construction, manufacturing, and many other industries. During the fabrication, machining (waterjet, diamond and band saws) and assembly of these laminate composites, various edge and hole delamination, fiber pullout and other micro and Nano cracks can be formed on the composite panels. The present study mainly focuses on the edge grinding and sealing of the machine damaged fiber reinforced composites, such as fiberglass, plain weave carbon fiber and unidirectional carbon fiber. The MTS tensile test results confirmed that the composite coupons from the grinding process usually produced better and consistent mechanical properties compared to the water jet cut samples only. In addition to these studies, different types of high strength adhesives, such as EPON 828 and Loctite were applied on the edges of the prepared composite coupons and cured under vacuum. The mechanical tests conducted on these coupons indicated that the overall mechanical properties of the composite coupons were further improved. These processes can lower the labor costs on the edge treatment of the composites and useful for different industrial applications of fiber reinforced composites.S. Ankrah et.al Football shin guards were evaluated against a kick from a studded boot. The bending stiffness of their shells, and their response when impacted by a stud, were assessed using finite element analysis (FEA) and determined experimentally. A test rig was constructed with the leg muscle simulated by flexible foam, with the force distribution along the tibia and to the lateral muscle measured using flexible force sensors. High-speed photography confirmed deformation mechanisms predicted by FEA. Load spreading from the stud impact site correlated with the guard shell bending stiffness. The best guards use shells of complex shape to increase their transverse bending stiffness.

CHAPTER 3 MATERIALS AND EXPERIMENTAL METHODS3.1Materials3.1.1Vacuum Bag Materials

Repairs of composite flying machine segments are frequently performed with a strategy known as vacuum bagging. A plastic bag is fixed around the repair zone. Air is then expelled from the bag, which permits repair plies to be drawn together with no air trapped in between. Atmospheric pressure bears on the repair and a solid, secure bond is made. A few handling materials are utilized for vacuum packing a part. These materials do not become part of the repair and are disposed of after the repair process. Different vacuum bagging materials are shown in the figure 7 below.

Figure 7: Vacuum Bagging Materials3.1.2Release Agents Release agents also called as mold release agents, are utilized so that the part falls off the device or caul plate easily after curing.

3.1.3Bleeder Ply The bleeder utilize makes a way for the air and volatiles to escape from the repair. Excess resin is gathered in the bleeder. Bleeder material could be made of a layer of fiberglass, nonwoven polyester, or it could be perforated Teflon covered material. The structural repair manual (SRM) shows what sort and what number of employs of bleeder are required. As a general rule, the thicker the laminate, the more bleeders plies are required. 3.1.4Peel Ply Peel plies are regularly used to make a spotless surface for holding purposes. A thin layer of fiberglass is cured with the repair part. Just before the part is bonded to another structure, the peel employ is removed. The peel ply is easy to remove and leaves a clean surface for bonding. Peel plies are produced from polyester, nylon, fluoronated ethylene propylene (FEP), or coated fiberglass. They can be hard to remove if overheated. Some coated peel plies can leave an undesirable contamination on the surface. The mostly used peel ply material is polyester that has been heat-set to dispose of shrinkage. Figure 8 illustrates the peel ply material.

Figure 8 :Peel Ply

3.1.14Layup Tapes To seal the vacuum bag to a part or tool layup tape is used which is also known as sticky tape. The temperature rating of the tape should be always verified to make sure that you use appropriately rated tape. Figure 9 shows the application of layup tape.

Figure 9: Application of Layup tape on the specimen3.1.5Perforated Release Film Perforated release film is utilized to permit air and volatiles out of the repair, and it keeps the bleeder handle from adhering to the part or repair. It is available with various size holes and hole spacing depending upon the measure of bleeding required. The perforated film shown in the figure 10 is used to allow air out of the repair material.

Figure 10: Perforated Release Film3.1.6Solid Release Film Solid release films shown in the figure 11 are used to ensure that the pre-preg or wet layup plies don't stick to the working surface or caul plate. It also prevents the resins from bleeding through and damaging the heat blanket or caul plate if they are utilized.

Figure 11: Solid Release Film3.1.7Breather Material The breather material shown in the figure 12 is utilized to give a way to air to escape the vacuum bag. The breather must contact the bleeder. Ordinarily, polyester is utilized as a part of either 4-ounce or 10-ounce weights. Four ounces is utilized for applications beneath 50 pounds for every square creep (psi) and 10 ounces is utilized for 50100 psi.

Figure 12: Breather Material

3.1.8Vacuum Bag The vacuum bag material gives an extreme layer between the repair and the air. The vacuum pack material is accessible in various temperature ratings, so ensure that the material utilized for the repair can deal with the cure temperature. Most vacuum bag materials are one-time use, however, material produced using adaptable silicon elastic is reusable. Two little cuts are made in the bagging material so that the vacuum test valve can be introduced. The vacuum bag is most certainly not extremely adaptable and plies should be made taken care of if complex shapes are to be bagged. At times, an envelope sort bag is utilized; however, the inconvenience of this strategy is that the vacuum weight may squash the part. Reusable bags produced using silicon rubber are accessible that are more adaptable. A few have an inherent radiator cover that disentangles the stowing undertaking. 3.1.9Vacuum Equipment A vacuum pump is utilized to empty air and volatiles from the vacuum bag so that atmospheric pressure consolidates the plies. A dedicated vacuum pump is used as a part of a repair shop. For repairs on the flying machine, a portable vacuum pump could be utilized. Most heat bonders have an implicit vacuum pump. Extraordinary air hoses are utilized as vacuum lines, since general air hoses may crumple when a vacuum is connected. The vacuum lines that are used in the oven or autoclave should be capable to withstand the high temperatures in the heating device. A vacuum pressure regulator is sometimes used to lower the vacuum pressure during the bagging process. The complete setup of vacuum bagging is illustrated in the figure 13. Figure 14 shows the test valve that is planted on the vacuum bag for carrying out the process.

Figure 13: Vacuum Bagging Set up

Figure 14: Test Valve3.1.10Drop weight TestDrop test is performed for a number of reasons one of them being to fabricate load tolerant goods, secondly to produce the damage data which may happen at the time of manufacturing, conveyance and using of the composite. Thirdly this test is used to estimate the life span of the product.A load is dropped in the vertical direction to impact the material which is to be tested. In this study drop wise test was used because of its real life conditions while testing. Low Velocity Impact testing was the most efficient test for this investigation. Low velocity drop test apparatus is shown in the below figure 15 with which the indentation is performed on the specimen. .Figure 15: Figure: Apparatus for the drop Wise test3.1.11Apparatus used for Measuring Thickness and other ParametersMicrometers and CalipersThe micrometer(s) shall be used for specimen length, width and thickness measurements, and shall use a 4 to 6 mm [0.16 to 0.25 in.] nominal diameter ball-interface on irregular surfaces such as the bag-side of a laminate, and a at anvil interface on machined edges or very smooth tooled surfaces. A caliper of suitable size shall be used for measurement of dimensions for detected damage. The accuracy of the instruments shall be suitable for reading to within 1 % of the specimen width and thickness. For typical specimen geometries, an instrument with an accuracy of 60.0025 mm [60.0001 in.] or better is desirable for thickness measurement, while an instrument with an accuracy of 60.025 mm [60.001 in.] or better is desirable for length, width, and damage dimension measurement.3.1.12C-Scan ImagesUltra sonic C-scan techniques of out dated carbon fibers. The Ultrasonic Inspection of the specimens was carried out by the pulse- Echo method. The C- Scan images are used to infer the delamination and other void in the structure of the panels. These images are processed by the ultrasonic waves. A quarter inch diameter uni-crystal transducer of 5 MHz from PANAMETRICS. The ultrasonic device which is generally used is a fully automated system which is known as ULTRAPAC II system. The Data for this c scan images is stored and re utilized for further calculation, control and imaging by using the software ULTRAWIN.In this Investigation of shin guards using outdated carbon fibers the C- scan Image set up was done at NAIR in WSU campus, Wichita, Ks. The Ultrasonic c-scan tank is shown in the figure 16 below.

Figure 16: Figure: Ultra Sonic C Scan Tank

3.2Experimental Methods3.2.1Test Procedure Carbon fiber panels with silicone rubber adhesively bonded were developed in this study. Four panels were fabricated for every kind of support to oblige the testing utilizing 1inch impactor at a given vitality level. Baseline models for the carbon fiber and woven fabric were taken into consideration and compared with the same models with silicone rubber adhesively attached to the baseline ones. Both the baseline and specimens were separately tested to impact. Carbon fiber composites were fabricated utilizing pre-pregs and Oven curing according to the producer details.3.2.2Mold PreparationEvery mold or lay-up surface might be tidied before lay-up, utilizing non-tainting cleaners, for example, acetone or alcohol. Mold arrangement should be performed outside the lay-up room. In the wake of cleaning, every mold might be treated with non-polluting discharge specialists in agreement with the supplier's guidelines. Thermocouple amount and area will be determined on the shop explorer.3.2.3Cutting and Lay upThe cutting and lay-up region might be kept free of contaminants. In the event that pre-preg laminations are pre-cut and assembled into packs for future lay-up and cure, the poly-film backing gave by PACM should not be expelled until every utilize is prepared to be put in the lay-up mold. Units might be put away in fixed, dampness verification compartments until prepared for lay-up. Upon expulsion from capacity, the pre-preg materials should be permitted to warm to room temperature inside the fixed dampness evidence pack for no less than 3 1/2 hours or until noticeable dampness has vanished from the outside of the sack. Any peel handle prerequisites will be determined on the drawing and/or shop explorer. Unless generally determined on the drawing, grafts are permitted. Be that as it may, they should cover by no less than one inch and no two grafts in a solitary handle should be nearer together than 24 inches. Least separation between grafts in adjoining plies is six inches. Butt joins are for the most part to be maintained a strategic distance from. On the off chance that butt grafts are utilized, the most extreme crevice anytime is 0.030 inches. Butt grafts might have one extra utilize of material, the same as the base overlay, stretching out for no less than one inch on either side of the graft joint. White, build up free cotton gloves are required for hand/individual insurance. Without talc latex on the other hand nitrile gloves are satisfactory substitutes. No cutting of pre-preg materials is allowed on the instrument. Figures 17,18 and 19 are the panels produced with unidirectional carbon fibers, woven carbon fibers with the layup sequence.

Figure 17: Carbon fiber panel with required orientation

Figure 18: Unidirectional Carbon Fiber Panel

Figure19: Woven Fabric Panel with The Required Orientation

Figure 20: Layup Orientation

Figure 21: Laminate Layup (Vacuum Bag and Port Not Shown for Clarity).The above figures 20 and 21 illustrates the layup orientation and the layup that is performed on the laminates.3.2.4Debulk ProcedureDebulking might be performed keeping in mind the end goal to accomplish suitable compaction. Debulking might be performed on the primary utilize and then extra debulks ought to be performed each two (2) plies of pre-preg with FAW of 500-900g/m2 on the other hand each three (3) plies of pre-preg of FAW of 300-500g/m2 on the other hand each five (5) plies of pre-preg with FAW 100-300g/m2a. Apply one layer of non-permeable discharge fabric over the pre-preg lay-up. b. Apply one layer of 340g/m2 (10oz/yd2) breather (N10 or two layers of N4) on top of the non-permeable discharge film. In the event that the breather is not tainted with pitch or other remote material, the breather might be re-utilized. c. Introduce nylon bagging film over the overlay or frame fit a silicone elastic pack and edge seal to the apparatus with vacuum sack sealant; introduce the vacuum connector through the sack. Utilize various vacuum connectors so that no point on the part is more than 60 inches from a vacuum source. Note: Install the vacuum connectors on the instrument surface outside the edge of the cover wherever conceivable. Setting the connector in a sack crease is a satisfactory exchange. On the off chance that that the mold is not sufficiently enormous to suit this kind of plan you can put the vacuum port on top of the part by collapsing the pack and utilize 4-6 plies of breather. d. Apply vacuum of no less than 25 inches Hg for no less than 15 minutes at a rate that does not cause the pre-preg to move. Figure 22 shows at the point when indicated by the appropriate shop explorer, the cover might be warmed to 1000F greatest and held for 10-15 minutes amid vacuum application however there might be close to six (6) debulks at 1000F on any lay-up. The last debulk might be for 30 minutes least.

Figure 22: Carbon fiber panel after applying silicone rubber adhesively and the plates on which the panel is to be placed.3.2.5Bagging ProcedureThe shop explorer will give particular guidelines with respect to the utilization of peel plies, bleeder materials, breather materials and bagging materials. The general methodology will be as per the following: a) The device is prepared with the proper mold discharge area 1. b) Apply the pre-preg on the discharge device. c) Apply one layer of peel utilize or equal the same size as the part. d) A Bleeder is prescribed if the sap substance of the pre-preg is more than 42% or for extremely thick part more than 0.5" thick. Two plies of 300gsm 7781 of E-Glass fabric or one utilize of 610gsm woven meandering can be utilized. e) Apply one layer on non-permeable discharge film, Teflon or proportional, over the lay-up; reaching out no less than 1/2 inch past every edge of the part. f) Apply one layer of breather fabric over the lay-up guaranteeing that it frames a way to the vacuum port. g) Vacuum sources are ideal not be on the surface of the part. 1) There ought to be no less than two (2) hotspots for any part bigger than four (4) square ft. For bigger parts, no less than one vacuum association ought to be accommodated each 18 square ft. of cover surface. 2) Where conceivable, the greatest separation to any point on the cover surface should not surpass 60 inches. Secure against obstructing with tar by applying additional breather under the vacuum port. 3) In the event that that the mold is not sufficiently huge to oblige this kind of course of action you can put the vacuum port on top of the part by collapsing the sack and utilize 4-6 plies of breather. h) Apply the nylon bagging film and edge seal to device with vacuum pack sealant. i) Clear the pack to no less than 25 inches Hg and conform the sack to take out wrinkles and crossing over. j) Introduce a vacuum gage at the vacuum probe connector. Permit the packed away get together to remain for no less than 15 minutes with a connected vacuum of no less than 25 inches Hg. Evacuate the vacuum source and screen the pack vacuum. Spillage may not surpass three (3) inches Hg in the initial five (5) minutes subsequent to evacuating the vacuum source. After completing the bagging procedure, the setup looks like in the figure 25 below.

Figure 23: After Bagging3.2.6Cure cycleAll pre-preg materials are to be cured by controlled time, temperature and, vacuum prerequisites. Quality Assurance might consistently record time, temperature and vacuum amid the cure process. Thermocouple wires ought to be utilized to screen and record the temperature of agent test panels. One technique is to put the thermocouple intersections at the overlay mid-plane and close to the edge of the cover where they will be trimmed off after the panels have been cured. The cure cycles used and the oven used is shown in the figures 26 and 27 respectively. Thermocouples might be set outside the pack just on the off chance that it has been beforehand exhibited that there is unimportant temperature distinction between within and outside of the pack.

Figure 24: Cure Cycles Information

Figure 25: Oven3.2.7Bag Removal and Part IdentificationBefore expulsion of the vacuum pack from the cured part, look at the sack for confirmation of ballooning, charring, rupture, pitch contact, tearing or other condition that would demonstrate pack disappointment amid the cure cycle. Record any perception of abnormal conditions on the shop voyager. Expel the vacuum sack. While expelling the cured cover from the device surface, keep away from the utilization of any sharp protests or instruments that could harm the surface of the part or the mold. Abstain from twisting the cured overlay or the subtle element part. Try not to evacuate any peel utilize as of now. Every part or gathering should be related to the particular part number, shop voyager number and cure cycle number. In the event that numerous parts are made on a solitary voyager (or Shop Request, Work Order, and so on.) then every individual part might be doled out a discrete serial number.

Figure 26: Test fixtures for the experimental study

Figure 27: Impactor used for the experimental study

.

CHAPTER 4RESULTS AND DISCUSSIONS4.1RESULTS Impact Testing: Dynatup 8250 impact unit was used to create impact damage on the composite panels. At energy level of 1500 in-lb./in and Tup impactor size of 1 inch were selected. The drop weight of the impact test setup was set to a certain height to achieve the required energy. The weight is then released to achieve kinetic energy at the point of impact. This kinetic energy is measured with the help of detectors as the impact energy. The impact load is measured with the help of a load cell. The principle of impact test is based on the law of the conservation of energy. The potential energy (E) attained by the total drop weight is given by: E=W*hEq. (1)Where w is weight (lb.) and h is the height (inch). As the impactor contacts the specimen, instantaneous forces and velocities are recorded. The impactor after impacting the specimen bounces back. Multiple impacts are prevented manually. Impact energy, absorbed energy and rebound energies are also reported for each specimen. Table 1 shows the Impact test matrix. Based on the thickness of each coupon and the energy level (in-lb./in), energy (in-lb.) is calculated for each test. Velocity, force and energy (in-lb.) are reported by the machine during the entire duration of testing. The difference between the impacted energy and the rebound energy is the energy required to create the damage inside the specimen. Figures 1a and 1b show the impact tower. Total drop weight is the sum of the weight of the cross head, extender, load cell and the impactor (tup). Total drop height is the distance between the top of the impact specimen and the tup. Figure 2 shows 3x5 inch opening on the support plates used to clamp the specimen. Specimen is securely held between the plates with the help of four corner screws so that the impact specimen cannot move during the impact test.4.1.1 Before Impact C- Scan Images

The C Scan images shown in the figures 28 and 29 gives us an idea of the delaminations and any other voids in the panels before the impact test is done on those panels.

Figure 28 : C scan Image before Impact of Uni directional carbon Fiber

Figure 29 : C- Scan Image before Impact of Woven fiber4.1.2Impact AnalysisImpact Energy= 1500in-lb/in Tup Diameter= 1in.The table below describes the dent depths of the different adherends used in the procedure which were carried out the drop test.

Table 1: Table: Dent Depths of specimensNameDent Depth

U-CF-1-10.0525

U-CF-1-20.0605

W-CF-1-10.0250

W-CF-1-20.0205

U-CF-1-1 With Silicone0.0335

U-CF-1-2 With Silicone0.0320

W-CF-1-1 with Silicone0.0165

W-CF-1-2 with silicone0.0185

The graph below in the figure 30 illustrates that the unidirectional carbon fiber and woven carbon fiber baseline models have higher dent depths compared to the silicone rubber bonded carbon fiber specimen.

Figure 30: Average dent depths of various composite panels4.1.2 After Impact C- Scan Images The figures 31 and 32 are the C Scan images of the unidirectional carbon fibers with silicone rubber bonded on it and the dent depths are very less for the silicone rubber carbon fibers thus improving the impact resistance of the panels.

Figure 31: After Impact 2-1A

Figure 32: After Impact 2-2 AThe below figures 33 and 34 illustrates the C scans of the woven fibers with silicone rubber on it and the dents are not clearly visible in woven fiber composites but the dent depths gradually decrease with the application of external foams..

Figure 33: Woven Fiber with silicone Rubber 3-1A

Figure 34: Woven fiber with silicone rubber 3-2 A

specimenthicknessImpact tupDrop heightDrop weightMaximum energyImpact velocityImpact energyTotal energyTotal time

PANEL2-1

0.110.62518.8168.771075.787247.28165.17151.266.7749

PANEL2-2

0.110.62518.8168.771201.177279.31167.17157.66.7505

PANEL3-1

0.150.62525.6598.77572.838462.38225.93223.1716.5283

PANEL3-2

0.150.62525.6598.77476.648474.54226.58222.2916.8823

Table 2 Raw data for the specimen

The above table2 shows all the parameters obtained after the impact drop test on the unidirectional and woven carbon fibers with silicone rubber bonded on them.4.1.4Graphical ModellingThe following graphical representation is shown to study the variation in the Impact load with respect to time and deflection individually. Also the variation in Energy with respect to time was studied with the Graphical Model.

Figure 35: Graph Energy v/s Time

Figure 36: Graph Load v/s Time

Figure 37: Graph Load Vs DeflectionThe above graphs were plotted for the data obtained from the unidirectional carbon fiber with silicone rubber and the figures 35,36 and 37 show the deviation of energy vs Time, Load vs time and load vs deflection.

Figure 38: Load vs time

Figure 39: Time vs Energy

Figure 40: Load vs DeflectionThe above graphs were produced for the woven fiber with silicone rubber adhesively applied over it and tested for drop at 1500 in.lb/in and tup size of 1 in. Load vs deflection is explained in figure 40 and energy vs time is explained in figure 39. Load vs time is compared in figure 38.

Energy v/s Time.

Figure 41: Figure Energy Vs timeThe Graph shows the energy absorbed of the different specimens with silicone and without silicone in its composition. It is inferred from the graph that the specimen with silicon absorbs lower energy than compared to the regular specimen without any silicone in the composition in the figure 41. Low absorbed energy here indicates the toughness of the material to break. Therefore, the specimen when silicone rubber is introduced has low absorbed energy and higher strength.Load V/s Time

Figure 42: Load vs TimeThe Graph shows the variation of load with respect to time in the figure 42. The specimen with silicone in its composition takes lesser load than compared to the specimen without silicone. As the time increases load reaches a maximum then dips to zero and remains constant.

Load V/s Deflection

Figure 43: Figure Load vs TimeFigure 43 shows that the graph plotted between load vs time and the graph explains us that as the load increases the deflection is such that it takes the opposite direction.

CHAPTER 5 CONCLUSIONResponses of the composite laminates to impact loading were studied experimentally. Two different kinds of adherend materials were used for the experimental study. Silicone rubber was adhesively bonded to the carbon plain and woven fibers. The fibers were laid up using quasi-isotropic lay-up sequence for the manufacturing of the adherends and all the adherends were 16 ply composites. A total of 8 test coupons were impacted The absorbed energies for the unidirectional carbon fibers and woven fibers were compared with and without silicone rubber adhesively bonded. The graphs show that the absorbed energies were high in silicone panels which in turn proves that the strength of those panels is better.

CHAPTER 6FUTURE WORKImpact drop test of composite materials is exceptionally pivotal keeping in mind the end goal to screen them for basic unwavering quality. Sway appraisal is an exceptionally expansive field study, and in this manner, further research is required. More research must be done in the range of examination of disappointment behavior after the preparatory flexible reaction of examples is subjected to extraordinary navigate loads, both logically and tentatively. Further work is additionally required in the zone of harm review and portrayal. Pressure after the effect examination technique covers the pressure lingering quality properties of multidirectional polymer grid composite overlaid boards, which can be tried utilizing ASTM D7137, "standard test strategy for compressive remaining quality properties of harmed polymer framework composite plates.'' This test can anticipate the harm resilience of the material, since the harm properties of the material are exceedingly dependent on the size, piece of the material, firmness, and so on ecological debasement influences these effect examples, substantial arrangements ought to thusly exist keeping in mind the end goal to enhance consumption resistance. What's more, pre-preg reusing ought to be considered, with a specific end goal to diminish the transfer of dangerous waste, landfill necessities, and the utilization of harmful items, since pre-pregs have constrained lifecycle, and the transfer of lapsed pre-pregs are to a great degree costly. At the point when composite materials neglect to capacity, they are generally decimated or castoff into landfills, because of the absence of reusing skill and the employments of reused composites and filaments. This has made an exasperating effect on the earth and economy because of deadly tar frameworks which are utilized to fabricate composite materials. The evacuation of this hazardous waste is exceptionally costly, so the effective utilization of materials is required. Presentation of conceivable enhanced procedure techniques, for example, use of scrap pre-pregs as fortifications in plastics and move of the recently prepare strategies into business division ought to be started. Likewise, reusing will ruin any shortcomings of these strands, particularly carbon filaments utilized today. The advanced shin protectors which are made of composites ought to be tried for the effect at which it achieves its limit. The spaces will help us figure the quantity of employs expected to get exact and exact results. The same boards can be utilized for effect testing which is the state of a shin protector to better evaluate the hassles at every purpose of the board fit as a fiddle.

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