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<p>Materials engineers are responsible for the research, specification, design and development of materials to advance technologies of many kinds. Their expertise lies in understanding the properties and behaviours of different substances, from raw materials to finished products. The field is also referred to as materials science or materials technology. They work with many different materials, including: ceramics; chemicals; composites; glass; industrial minerals; metals; plastics; polymers; rubber; textiles.</p> <p>y y y y y y y y y y</p> <p>Working in a diverse range of industries, materials engineers combine or modify materials in different ways to improve the performance, durability and cost effectiveness of processes and products. For ideas about the range of careers in materials engineering and science, go to UK Centre for Materials Education (UKCME) .</p> <p>Typical work activitiesWork activities vary according to the specific material and industry you work with, and the size of the organisation you work for, but there are a number of activities common to most posts. These include: selecting the best combination of materials for specific purposes; testing materials to assess how resistant they are to heat, corrosion or chemical attack; analysing data using computer modeling software; assessing materials for specific qualities (such as electrical conductivity, durability, renewability); developing prototypes; considering the implications for waste and other environmental pollution issues of any product or process; advising on the adaptability of a plant to new processes and materials;</p> <p>working to solve problems that may arise either during the manufacturing process or with the finished product (e.g., problems caused by daily wear and tear or change of environment); y supervising quality control throughout the construction and production process; y monitoring plant conditions and material reactions during use; y helping to ensure that products comply with national and international legal and quality standards; y advising on inspection, maintenance and repair procedures; y liaising with colleagues in manufacturing, technical and scientific support, purchasing, and marketing;</p> <p>y y y y y y y y</p> <p>y y y</p> <p>supervising the work of materials engineering technicians and other staff; considering the costs implications of materials used and alternatives, in terms of both time and money; taking account of energy usage in manufacturing and in-service energy saving, e.g., in transport and construction applications.</p> <p>At senior level, the work is likely to involve more innovative research or greater management responsibility. The latter will call for a range of additional skills that are not necessarily part of the routine work of a materials engineer.</p> <p>Materials engineers are responsible for evaluating materials and creating plans and processes for manufacturing products from various raw materials. The machines they develop may be specialized for specific products. Materials engineers create machines that create products from one type of material such as metal, graphite, glass, plastic and other natural resources. As long as society needs material for construction and products that will be sold either to other consumers in or out of the country, materials engineers will be needed.</p> <p>Responsibilities1. Materials engineers may analyze and interpret data or laboratory results that can cause a problem or failure within the machines. They may create their own tests and supervise existing tests on raw materials, as well as finished products to determine its quality. They take under consideration economic factors such as pollution and costs to create the best method of creating a product from raw materials. They may solve any issues within the industries of mechanical, chemical, electrical and nuclear products. They may train and supervise a technical staff in developing any materials and products for future devices or natural products. They try to find synthetic ways of replicating natural materials such as metals, glass, etc.</p> <p>Skills</p> <p>2. Materials engineers must have science skills, be proficient in math, technology, reading comprehension, effective communication and problem-solving skills. Analytical skills are needed to understand and interpret data from materials and machines. Advanced writing skills, researching, deductive and inductivereasoning, and interpreting information in order to convey to others are also necessary skills.</p> <p>Similar Job Titles</p> <p>3. Materials engineers can receive a bachelor's degree in materials engineering. The materials engineer program prepares students for the mathematical and science necessary to design, develop and operate various machines to bond, extract and create natural or synthetic materials. Students may have to considerresearching various schools in the area or out of state for specific material engineer degrees.</p> <p>What is material engineer job description?Material engineer is responsible for the research, specification, design and development of materials to advance technologies of many kinds of material. His or her expertise lies in understanding the properties and behaviors of different materials start from raw to finish products. They also called as materials technologist or materials scientist. They work with many different materials, including: metals; industrial minerals, composites, ceramics, glass, chemicals, plastics, polymers, rubber. Material engineer job description is diverse range of industries, aim to combine or modify materials in different ways to improve its performance, durability and off course cost effectiveness of processes and products.</p> <p>Typical Material Engineer Job DescriptionWork activities vary depend on the industry where the material engineer works with. However, typical material engineer job description or activities include: select the best combination of materials for specific purposes. Testing materials both destructive test or non destructive test to assess how tolerant they are to bending, tension, heat, corrosion or chemical attack, Assessing materials such as electrical conductivity or durability. Evaluate industrial minerals such as silica, sands, dolomites, limestones, magnesite, etc for glass or refractory manufacture. consider the implications for waste and other environmental pollution of any product or process. advise on the adaptability of a plant to new processes and materials. Problem solving which may arise either during the manufacturing process or with the finished product such as crack, wear and tear, or change of Supervise related to quality control throughout the construction and production process. Monitor the conditions reactions of material during use. Ensure that the products comply with national and international legal and quality standards such as ASTM, ASME, etc Advise on inspection, maintenance and repair procedures. Supervise the work of materials engineering technicians and other staff. Review the cost implications of materials used and alternatives, in terms of both time and money. Review the energy usage in manufacturing and in-service energy saving, e.g. in transport and construction applications. Research and develop materials which are amenable to recycling.</p> <p>y yetc.</p> <p>y y y y yenvironment.</p> <p>y y y y y y y y</p> <p>Document Review</p> <p>y y y y y y y</p> <p>Bid/project specifications and design Special provisions Agency requirements Traffic control plan Equipment specifications Manufacturers' instructions Material safety data sheets (if required for concrete slurry)</p> <p>Concrete Mixers and Concrete Mixing Methods:Introduction As for all materials, the performance of concrete is determined by its microstructure. Its microstructure is determined by its composition, its curing conditions, and also by the mixing method and mixer conditions used to process the concrete. The mixing procedure includes the type of mixer, the order of introduction of the materials into the mixer, and the energy of mixing (duration and power). To control the workability or rheology of the fresh concrete, for example, it is important to control how the concrete is processed during manufacture. In this overview, the different mixers commercially available will be presented together with a review of the mixing methods. Further, the advantages and disadvantages of the different mixers and mixing methods and their application will be examined. A review of mixing methods in regards to the quality of the concrete produced and some procedures used to determine the effectiveness. of mixing methods will also be given. To determine the mixing method best suited for a specific application, factors to be considered include location of the construction site (distance from the batching plant), the amount of concrete needed, the construction schedule (volume of concrete needed per hour), and the cost. However, the main consideration is the quality of the concrete produced. This quality is determined by the performance of the concrete and by the homogeneity of the material after mixing and placement. There should be a methodology to determine the quality of the concrete produced, but only few methods and only one attempt of standardization were found in the literature. The methodology to determine the quality of the concrete mixed is often referred to as the measurement of the efficiency of the mixer. The efficiency parameters of a mixer are affected by the order in which the various constituents of the concrete are introduced into the mixer, the type of mixer, and the mixing energy (power and duration) used. The Mixers Batch mixers Mixers that produces concrete one batch at a time, and needs to be emptied completely after each mixing cycle, cleaned (if possible), and reloaded with the materials for the next batch of concrete. In the second type, the constituents are continuously entered at one end as the fresh concrete exits the other end. The various designs of each type of mixer will now be discussed. The two main types of batch mixer can be distinguished by the orientation of the axis of rotation: horizontal or inclined (drum mixers) or vertical (pan mixers). The drum mixers have a drum, with fixed blades, rotating around its axis, while the pan mixers may have either the blades or the pan rotating around the axis. Drum Mixers All the drum mixers have a container with a cross section. The blades are attached to the inside of the movable drum. Their main purpose is to lift the materials as the drum rotates. In each rotation, the lifted material drops back into the mixer at the bottom of the drum and the cycle starts again. Parameters that can be controlled are the rotation speed of the drum and, and in certain mixers, the angle of inclination of the rotation axis. Mixing Method In describing the mixing process, the mixer hardware is only one of several components. The mixing process also includes the loading method, the discharge method, the mixing time, and the mixing energy. Loading, Mixing, and Discharging The loading method includes the order of loading the constituents into the mixer and also the duration of the loading period. The duration of this period depends on how long the constituents are mixed dry before the addition of water and how fast the constituents are loaded. The loading period is extended from the time when the first constituent is introduced in the mixer to when all the constituents are in the mixer. RILEM (Reunion Internationale des Laboratoires dEssais et de Recherches sur les Materiaux et les constructions) divides the loading period into two parts: dry mixing and wet mixing. Dry mixing is the mixing that occurs during loading but before water is introduced. Wet mixing is the mixing after or while water is being introduced, but still during loading. This means that materials are introduced any time during the loading period: all before the</p> <p>water, all after the water, partially before and partially after. The loading period is important because some of the concrete properties will depend on the order in which the constituents are introduced in the mixer. It is well known that the delayed addition of high range water reducer admixture (HRWRA) leads to a better dispersion of the cement. The same workability can be thus be achieved with a lower dosage of HRWRA. The discharge from the mixer should be arranged so that it increases productivity (fast discharge), and it does not modify (slow discharge) the homogeneity of the concrete. For instance, if the discharge involves a sudden change in velocityas in falling a long distance onto a rigid surface there could be a separation of the constituents by size or, in other words, segregation. Mixing Energy The energy needed to mix a concrete batch is determined by the product of the power consumed during a mixing cycle and the duration of the cycle. It is often considered, inappropriately, a good indicator of the effectiveness of the mixer. The reason that it is not a good indicator is because of the high dependence of the power consumed on the type of mixture, the batch size and the loading method. For example, a mixer that has a powerful motor could be used to mix less workable or higher viscosity concretes. The mixing energy could be similar to that of a less powerful mixer but one filled with a more workable concrete. Mixer Efficiency As it has been pointed out, the variables affecting the mixing method are numerous, not always controlled, and not a reliable indicator of the quality of the concrete produced. There is, therefore, a need for a methodology to determine the quality of the concrete produced as an intrinsic measure of the efficiency of the mixer. The concept of mixer efficiency is used to qualify how well a mixer can produce a uniform concrete from its constituents. RILEM defines that a mixer is efficient if it distributes all the constituents uniformly in the container without favoring one or the other. Therefore, in evaluating mixer efficiency, properties such as segregation and aggregate grading throughout the mixture should be monitored. Steel D Concrete Mixe 4c Electric 4c Poly D Concrete Mixe 6c Electric 6c 6c Electric 6c</p> <p>6c</p> <p>6c</p> <p>6c</p> <p>9c Electric 9c</p> <p>9c Electric 9c</p> <p>9c</p> <p>ConcreteConcrete surfaces (specifically, Portland cement concrete) are created using a concrete mix of Portland cement, gravel, sand and water. The material is applied in a freshly-mixed slurry, and worked mechanically to compact the interior and force some of the thinner cement slurry to the surface to produce a smoother, denser surface free from honeycombing. The water allows the mix to combine molecularly in a chemical action called hydration. Concrete surfaces have been refined into three common types: jointed plain (JPCP), jointed reinforced (JRCP) and continuously reinforced (CRCP). The one item that distinguishes each type is the jointing system used to control crack development.</p> <p>Join...</p>