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TASK 4 BIOMEDICAL ENGINEERING REPORT

Engineering Studies Assessment Task 4

(Bio Medical Engineering)

SN:#30604172

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Table of ContentsSocial & Ethical issues within Biomedical Engineering.........................................................................4

Engineering Report:..............................................................................................................................5

Abstract:...................................................................................................................................................5

Introduction:.............................................................................................................................................5

Analysis:..................................................................................................................................................6

Inventions that have shaped Biomedical engineering: The artificial heart..........................................6

Materials that are commonly used within biomedical engineering:........................................................6

Stainless steels.....................................................................................................................................7

Polymers..............................................................................................................................................8

Titanium...............................................................................................................................................8

Ceramics..............................................................................................................................................8

Processes used within biomedical engineering materials:.......................................................................9

Forging.................................................................................................................................................9

Blacksmithing:.....................................................................................................................................9

Drop Forging:......................................................................................................................................9

Press Forging:......................................................................................................................................9

Swagging:............................................................................................................................................9

Casting:..............................................................................................................................................10

Sand casting.......................................................................................................................................10

Investment Casting:...........................................................................................................................10

Polymers:...............................................................................................................................................11

Thermoforming (Polymers):..............................................................................................................11

Fabrication:............................................................................................................................................11

Welding..............................................................................................................................................11

Brazing...............................................................................................................................................12

Soldering............................................................................................................................................12

Bolting...............................................................................................................................................12

Grain Structures and their effects within casted products and forge products:.....................................12

Casted products:.................................................................................................................................12

Forged products:................................................................................................................................13

Innovations occurring within biomedical engineering:.........................................................................13

Tissue engineering:............................................................................................................................13

Neural engineering.............................................................................................................................14

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Microbubbles.....................................................................................................................................14

Conclusion:............................................................................................................................................14

Appendix:...............................................................................................................................................15

Bibliography:.........................................................................................................................................20

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Social & Ethical issues within Biomedical EngineeringBio Medical Engineering is a study and application that specialises both in engineering and medical biology providing solutions and testing of biological problems. Biomedical engineering is responsible for the development and invention of prosthetic limbs, body parts and organs. This development in biomedical engineering has led to a social and ethical issue within testing, materials, cost and hazards of biomedical engineering. The aims of this report are to examine these social and ethical issues.

Belief and religious concerns:

Biomedical engineering is constantly evolving and developing in major transitions leading to more newer research in newer fields which is good for the ongoing development and advancement of biotechnology since many human parts can be replaced. But, this can cause problems since body parts such as the (nervous system, eyes, heart, ankles, muscle tissue, sperm or eggs etc.) require such biological forces that cannot be replaced or fixed with biotechnology, generating religious and environmental concerns within society because the use of biotechnology may contravene with their beliefs. Consequently, before the patient or victim is getting an implant they must have full consent and must be ok with getting the implant for belief reasons. If they are not ok with the implant, then they will need to be faced with an alternative option

Health and Safety risks within materials:

Due to the diverse field of bioengineering one of the biggest social and ethical issues are health and safety matters. Biomedical engineering requires the use of using materials to replace broken parts. However, these materials must be biocompatible. If a material implanted within the body is not appropriate and reacts with the body then serious risks and health hazards may occur, e.g. blood poisoning, cancer, infections. Therefore, all surgery and material testing and development must be done to an acceptable & safe standard so that these hazards can be avoided and the invention can be used without concerns.

Funding:

Finding the right material and manufacturing with the material may financially impact the company or the funding (company, organisation) leading to more expenses to be paid for the patients. This would have a major impact on the business (especially if the organisation is government or tax payer funded) leading to less financial support. Causing a cease in major developments for biomedical engineering.

Ethical Testing:

Within ethical issues one major concern from society is the testing methods. These can range from:

Who/what is being tested

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Why are they being tested How will they be tested

In Australia, general testing is done on animals and then tested on humans. This is done in a legal and ethical way that does not harm the test subject which also follows guidelines that are set down by the Animal Welfare Acts (AWA). However, some testing may require certain subjects or specimen for validity reasons.

Since the testing is related to the biomedical field, society generally does not have a positive opinion on biomedical engineering leading to more arguments and debates whether the testing is ethical or not. An example of this can be the recent developments of sperm modifications and neuro-modifications (brain). Causing a fear or controversy within society because of religious beliefs and unknown side effects thus, not being able to find test subjects leading to financial impacts.

In conclusion of this report the main social and ethical issues of biomedical engineering are religious concerns, health and safety risks, funding and ethical testing. In which all showed positive contributions to biomedical engineering but had major setbacks which needed certain processes to be done that would address these problems.

Engineering Report:

Abstract:This report is about the developments of biomedical engineering and their new innovations that are occurring in the biomedical engineering field. This report also analyses biomedical inventions ad their processes such as forging, casting, vacuum forming and fabricating. And the differences between a casted, machined product compared to a forged product.

Introduction:Biomedical engineering is the application of creating solutions and problem solving techniques that confront problems within the field of medicine and biology. Biomedical engineering dates to almost 30 centuries ago when ancient methods were first to create solutions to biological problems such as prosthetic limbs and implants. Eventually constant research, development and advancement of technology have shaped newer methods for these biological problems and have significantly impacted the average life span of humans. However, because biomedical engineering is such a diverse field, inventors, researchers, manufacturers and test subjects must follow and ensure certain factors are met such as

Constant developments and advancements within new innovations and their control & testing methods.

The materials used in biomedical engineering. The manufacturing processes of these materials.

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The aims of this report are to outline and discuss these certain processes and factors that biomedical engineers face and to provide reasons for and/or against these methods or developments.

Analysis:

Inventions that have shaped Biomedical engineering: The artificial heartOne of the most crucial influences within bio medical engineering are the inventions that have been developed from solutions to biological and medical problems. The artificial heart is an invention that replaces the heart for a device which can pump blood to the body. Initially the artificial heart was designed to bridge the time during a heart transplant surgery. Design and research were done in the 1940s and eventually took 42 years until the first successful artificial heart had been implemented.

There are mainly two types of artificial hearts:

One that provides an extra ventricle to stop blood clots from forming (Ventricular Assist Device) Fig1.1

One that totally replaces your heart (Total artificial heart) Fig 1.2

Your heart works by pumping blood and distributing it all around your body. When blood enters the artificial heart from either the led or right atrium ( the chamber that receives blood) it is pumped into the aorta (artery to the body) or the pulmonary artery (artery to the lungs) depending which side of your heart is being supported.

An artificial heart is powered by air or electricity, a cable connects to the pumping system in your heart and a console that controls and regulates the pump function. This console is either a big box with wheels or if the patient needs a permanent artificial heart then a mini console connected to a belt or vest can be worn for more mobility and freedom.

These devices are made from titanium and plastic. This is because titanium and plastic do not react with the body and is also very durable. An artificial heart can last from several weeks to over a few years.

The development of artificial hearts are one of the biggest contributions to biomedical engineering and is constantly evolving. Biomedical engineers are now looking at ways to:

Find newer materials to create these artificial hearts. To grow artificial hearts therefore creating a heart that will not react with the body

and does not require an electronic system or external control system Shrink the size of these artificial hearts therefore making them smaller and easier Reducing surgery time so that fewer risks occur.

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Materials that are commonly used within biomedical engineering:Bioengineering requires the skill of using materials that are highly biocompatible. If not serious hazards can occur. Therefore, a bioengineer must choose the right materials to work with. Generally, regular engineers look for these properties within materials:

Modulus of elasticity Tensile, Compressive and shear strength Yield Strength Ductility Hardness and toughness

However, when a Bioengineer chooses certain materials they must also consider:

Corrosion and corrosion resistance Crevice corrosion Pitting corrosion Galvanic corrosion Electrochemical corrosion Clinical significance of corrosion

The most common used materials within bio engineering are:

Stainless steelsStainless steel is an alloy of steel. One of its main advantages within bioengineering is its ability to form a thin oxide layer on its surface within the atmosphere or body fluids therefore, making it biocompatible. This thin oxide layer can resist corrosion and is stable making it able to protect the components or other materials within the biomechanical part. Regular steel such as tool steel or mild steel, are the least suitable steels since they can release and dislodge microscopic particles that will be rejected by the body causing infections and hazards to the body.Stainless steel is commonly used in surgical pins, bionic ears and artificial hearts.

Stainless steels are also very expensive. Not only to buy but to produce and fabricate since stainless steel is one of the hardest materials to fabricate and weld with because of its high heat dissipation time compared to other materials.

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A thermal conductivity table comparing the thermal conductivity of stainless steel to other metals.



















PolymersPolymers are also used in a variety of biomedical components since they have a stable and inert nature with the body. Many polymers are used within implants and artificial limbs, breast implants and smaller components within biomedical devices. Polymers are also responsible for applications such as crating a biocompatible housing that weighs less than stainless steel. Still today, polymers are still being researched for further advancements such as nanotechnology, genetics, wound closures, bone regeneration, tissue engineering and even virus control. Polymers are also considered environmentally friendly since they are biodegradable but due to the intensive interaction with body fluids that contain chemicals, they can also degrade into the body leading to wear and tear. Polymers have also been proven to absorb important nutrients and water from blood thus another disadvantage.

TitaniumOne of the most common materials used in biomedical engineering is titanium. Titanium is not only biocompatible but has an excellent strength to weight ratio and has a high fatigue. Titanium, just like stainless steels, forming an oxide layer when exposed to body parts or body fluids thus, less resistance to corrosion making it one of the most lightweight- durable and biocompatible materials to use for biomedical engineering. However, since titanium is hard to extract it is expensive costing more to develop and test with.

Titanium is commonly used in prosthetics such as hip joints, knee joints, bone plates and screws, dental plates, pacemakers and anything from small to large, since it has great machinability. Another one of titanium’s advantages is the ability to be detected or compatible with computer tomography scans (CT) or Magnetic Resonance Imaging scans (MRI).

CeramicsCeramics are used in biomedical engineering as a less ductile material. This is good for components that relate to bones such as tooth filler and bone filler. Ceramic materials are mainly for orthopaedics, dentists and neurosurgeons. Ceramics are also used to coat on prosthetics so that the parts will biologically bond with bones.

Just like stainless steels and titanium, ceramics are hard to manufacture, giving it a higher cost and expensive process. Ceramics can also minimize bone ingrowth and their implants can become loose making them dislodged.

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Processes used within biomedical engineering materials:As these materials are created and used for bodies the biomedical engineer must know what process they will be using to create the part to ensure the part is long lasting and biocompatible.

ForgingIn general, Forging is when a steel or metal is crushed into its desired form. This creates an even, flowing grain structure within the material giving it a longer lasting property.

Refer to Fig 3.1 in appendix

There are 3 main types of forging that is used within biomedical steels and metals.

Blacksmithing Drop Forging Press Forging Swagging

Blacksmithing:The oldest form of forging. Involves heating the metal to a temperature that makes the metal plasticise and then deformed with a hammer into the desired shape. The main disadvantages of blacksmithing are the size inaccuracy and the amount of labour for a small outcome. Blacksmithing was mainly popular in the past but after advancements within manufacturing technology black smithing is now rarely used within biomedical engineering except for surgical tools.

Drop Forging:Drop forging is the technique that uses a hydraulic hammer that pounds the metal into the desired shape. The heated metal can be put onto a die with the desired shape and then pounded continuously so that the metal forms into the die with the shape. However, even with a dimensional die, drop forging has the disadvantage of being size inaccurate compared to machining but has the advantage of grain flow.

Press Forging:Like drop forging, but slower. Press forging is when the metal is put onto the die and pressed slowly squeezing the metal into the desired shape. This requires a lot of hydraulic pressure and bigger machinery leading to higher costs.

Swagging:Main process for the forging of cylindrical bars, rods or tubes. Only used for increasing or decreasing diameters. This is done by forcing the tube into a die that is wider or has a smaller die in the middle to decrease cross sectional area. These dies can also be different shapes so that hexagonal structures can be made for fittings.

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Casting:Casting is the process of pouring molten metal into a mould to form the shape. After the metal cools down the metal solidifies, making it into a solid mould. Then further machining and fabrication can be done to enhance the look of the final product.

within manufacturing there are many different types of casting each having their own advantages and disadvantages.

Sand castingSand Casting is the most common form of casting, used in a variety of industries to mould, process or form using a sand mould. It requires the use of a furnace, metal, pattern and sand mould.

This application is commonly used to mould or process a variety of metal components with complex shapes. Regardless of weight and size sand casting can be used to form large objects such as heavy machinery components and housings for large equipment. Smaller components such as prosthetic legs, hips and surgical equipment. However, sand casting is labour intensive and is dimensionally inaccurate from shrinking.

The sand mixture is firstly mixed and formed. Then the mixture is put on top of a pattern within a casting box. Then once the sand mixture put on top it is then rammed and compacted to ensure the mould does not fall apart when the metal is poured in.

After, the other side of the pattern is positioned and a riser and gate plug is positioned. And then the sand is poured and compacted again. Then the casting box is split apart and all patterns and risers are taken out. The ingot (inside a ladle) is then heated in a furnace until it reaches melting point and the molten metal is poured into the mould.Once the product is formed, solidified and cooled. The product gets taken out to be machined and fabricated.

Refer to fig 4.1 in appendix

Investment Casting:Commonly known as lost wax casting. Investment casting is when patterns are moulded from wax. Then the wax patterns are dipped in multiple layers of ceramic slurry which can withstand high temperatures. Once the ceramic slurry is dried out the wax is melted inside without destroying the ceramic slurry. Then the molten metal is casted into the ceramic slurry solidifying into the moulds. After everything is solidified and cooled down the ceramic is smashed and the metal castings are then pulled out leaving a final product.

Investment casting is not only efficient witch large quantities but is dimensionally accurate and has a finer finish. However, investment casting is high in cost for materials, labour and equipment. Refer to fig 4.2 in appendix

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Polymers:Within the processes for polymers there is only one main process for polymers within biomedical engineering. Since polymers are mainly thermosetting or Thermosoftening they cannot follow the same process of forging or casting and must use other forms of processes that will not burn the polymer or break the polymer.

Thermoforming (Polymers):Thermoforming is a process used in polymers to quickly form sheets of materials into three dimensional shells. Firstly, a sheet of Thermosoftening polymer is heated on top of the machine. Then the pattern is then placed on top of the forming bench which has a series of holes connected to a vacuum. Then the top collapses and drops the heated sheet of polymer on top of the pattern creating a blanket. The vacuum then sucks and tightens the polymer on top of the pattern cooling and forming the mould of the pattern. This can be used for tool holders, bionic ears, complex shapes or even components within a part. Thermoforming is low cost and easy to do however generally the materials are weak and tend to break easily.


Fabrication:Fabrication is the process of constructing the individual parts and putting them together. These types of fabrication are:

WeldingWelding is the joining of two metals by fusing an external piece of metal that will melt and overlay the two metals thus, joining them together. There are 3 main types of welding.

MIG welding (Metal Inert Gas) is when a high current is passed through a thin piece of wire electrode that will melt once the high current passes through it. As the wire is fed onto the piece of metal (held by a grounding clamp) the electrode melts into the two joining pieces fusing them together. At the same time a shielding gas is released to prevent oxidisation during the welding. MIG welding is only used for carbon steel, stainless steel, aluminium, magnesium, copper, nickel, silicon bronze and other alloys.

TIG welding (Tungsten Inert Gas) is the same as MIG but however the shielding gas consists of Tungsten instead of other noble gasses. TIG welding is more accurate, easy to use and more concentrated. TIG welding is only used for thin sections of stainless steel and nonferrous metals.

Oxy acetylene welding is when gas and heat energy is used to melt a rod of the joining material. Oxy acetylene can weld most metals since it does not need to pass and electric current through them.


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BrazingBrazing describes the process of joining two sheets of steel together with a brass alloy the parent metal is heated to a temperature higher than the melting point of brass. Then the brass is placed onto the material causing it to become liquid and flow into the gap bonding the two metals together.


SolderingSoldering is just like brazing but instead using a material called solder (an alloy of lead). This makes the process easier since it has a lower melting point and is more controlled with a lower risk of burning yourself. Soldering is used for major electrical work to join wires together.


BoltingBolting is when a hole is drilled, tapped out with a spiral pattern inside. The bolt is a long piece of steel which has a thread on the surface (Spiral pattern). This bolt is then screwed into the threaded hole and held by friction. Bolts can be obtained from 1mm in diameter to 300mm in diameter.


Grain Structures and their effects within casted products and forge products:

Casted products:Casting is a cheaper way to make products when it comes to another method of forming. One major difference with casting is the physical properties that need to be considered. This is so that even knowing casted products are not as strong they still have to be assured that it is of the highest quality. Time, heat and material need to be considered as factors of casting to determine the quality.

If the material has a quick cooldown temperature, then finer grain structures are formed. If the material has a slow cool down temperature, then it will have larger grain structures. The direction of the grain structure within the metal can be determined by the direction of the heat that was removed.

The mould material can also affect the quality of the product such as if the mould was made from sand then crystallisation happens on the outer surface of the mould, forming small grains called chill grains. In which once the mould has fully cooled all the chill grains then formations of larger grains form known as columnar grains. These grains grow in the direction of the heat dissipation.

Refer to fig 3.2 in the appendix

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If different materials were put in different ways then the casting grain structure can be altered. For example, if two metal sides were used adjacent to two sand mould sides the grains would be lengthy towards the sides of the metal side. Since the heat dissipation is drawn out more within the metal sides.

fig 3.3 in appendix

However, this forms shear planes from a weak core, this is avoided by forming equiaxed grains. This is when the grains are equal in length which can withstand forces equally in all sides. To do this the casting temperature is monitored and controlled so that chill grains are formed, then columnar grains are formed and by slowly cooling off the core equi-axed grains are formed.

fig 3.4 in appendix

This process is a great way to strengthen the casted metal, but is a long and slow process. also, the labour required for preparation of different materials is intensive.

Forged products:Forged products are more expensive than casted products because they are better quality, tougher, harder and more durable.

Forged products harness these properties because of their different grain structure. Instead of having the problem of directional shear points and the use of equiaxed grains, forged products have a grain flow that follows the profile of the product as shown in figure 3.5 in appendix. Therefore, no shear points or weak planes exist and the product is tougher, harder and more malleable rather than brittle.

Forged products however, are way more labour intensive, time consuming, expensive and can prevent work hardening on the product.

Innovations occurring within biomedical engineering:Everyday biomedical engineers are constantly trying to develop newer innovations within control methods, materials used and inventions. These innovations are highly beneficial since they can increase the average human life span but can harness social and ethical issues.

Tissue engineering:Tissue engineering is the use of combining cells, materials and methods to form and grow human tissue. This can also be applied to growing bones, cartilage, muscles and blood vessels. This type of engineering requires the newer development of advanced polymers and materials. Tissue engineering can be used for people who have major skin conditions or need new body parts that are not mechanical.

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On the other hand, tissue engineering deflates the belief of being all natural and develops religious concerns. There is also a concern of the control methods if the original growing sample has a hidden disease then it can easily spread to patients.

Neural engineeringNeurological engineering is about the engineering of neuro systems (nervous systems) this research looks at repairing neurological paths, creating neurological paths with computers and even has links to robotics such as a brain wired prosthetic arm.

Neural engineering began in the brink of 2004 and has started to become more advanced ever since. However, lack of test subjects has led to slow developments within this technology. The benefits of neural engineering are being able to communicate with computers; therefore, humans can link and receive computer signals to control and harness computers and electrical components.

The disadvantages are mainly the ethical issues, the fact that it is not right to alter our body in an unnatural way. Also, a fear of computers taking control of the neurologically connected patient is an issue.

MicrobubblesMicrobubbles are bubbles that are smaller than 1 millimetre in diameter, but larger than one micrometre. These microbubbles can harness drugs inside and can be injected into the body allowing the drugs to flow directly to the designated spot. They can also contain nonhazardous chemicals as a contrast agent for ultrasound imaging.

The advantages of microbubbles are the accessibility for more information to be received during an ultrasound. Also for drug delivery purposes, microbubbles are the most efficient and quickest way of getting drugs into the designated area.

However, microbubbles are expensive to make, form and create. Microbubbles can also be lethal if they have been injected incorrectly as it can allow air into the blood system.

Conclusion:The development of biomedical engineering is dependent on the processes and materials were chosen which determine the quality and usability of the product. As these processes, all have specific pros and cons, the choice is also dependent on the situation.

Biomedical engineers not only face the difficulties within processes and material choices but also the social and ethical issues within society and society’s opinion of biomedical engineering.

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Appendix:

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Fig 1.1 A totally artificial heart.

Fig 2.2 A ventricular assist device attached to a patient. Fig 2.2 A ventricular assist device attached to a patient. Fig 2.2 A ventricular assist device attached to a patient. Fig 2.2 A ventricular assist device attached to a patient. Fig 2.2 A ventricular assist device attached to a patient. Fig 2.2 A ventricular assist device attached to a patient. Fig 2.2 A ventricular assist device attached to a patient. Fig 2.2 A ventricular assist device attached to a patient. Fig 2.2 A ventricular assist device attached to a patient. Fig 2.2 A ventricular assist device attached to a patient. Fig 2.2 A ventricular assist device attached to a patient. Fig 2.2 A ventricular assist device attached to a patient. Fig 2.2 A ventricular assist device attached to a patient. Fig 2.2 A ventricular assist device attached to a patient. Fig 2.2 A ventricular assist device attached to a patient. Fig 2.2 A ventricular assist device attached to a patient. Fig 2.2 A ventricular assist device attached to a patient. Fig 2.2 A ventricular assist device attached to a patient.

Fig 1.1 A totally artificial heart.Fig 1.1 A totally artificial heart.Fig 1.1 A totally artificial heart.Fig 1.1 A totally artificial heart.Fig 1.1 A totally artificial heart.Fig 1.1 A totally artificial heart.Fig 1.1 A totally artificial heart.Fig 1.1 A totally artificial heart.Fig 1.1 A totally artificial heart.Fig 1.1 A totally artificial heart.Fig 1.1 A totally artificial heart.Fig 1.1 A totally artificial heart.Fig 1.1 A totally artificial heart.Fig 1.1 A totally artificial heart.Fig 1.1 A totally artificial heart.Fig 1.1 A totally artificial heart.Fig 1.1 A totally artificial heart.


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Figure 6.2 The brazing process using a furnace. As the material is left in the corner and is melted from the furnace, it fuses the two materials together.

Figure 6.3 The soldering process. mainly a diagram of the tip . very similar to brazing

Figure 6.4 The bolting process. Notice the threads within the end of the bolt.

Figure 6.2 The brazing process using a furnace. As the material is left in the corner and is melted from the furnace, it fuses the two materials together. Figure 6.2 The brazing process using a furnace. As the material is left in the corner and is melted from the furnace, it fuses the two materials together. Figure 6.2 The brazing process using a furnace. As the material is left in the corner and is melted from the furnace, it fuses the two materials together. Figure 6.2 The brazing process using a furnace. As the material is left in the corner and is melted from the furnace, it fuses the two materials together. Figure 6.2 The brazing process using a furnace. As the material is left in the corner and is melted from the furnace, it fuses the two materials together. Figure 6.2 The brazing process using a furnace. As the material is left in the corner and is melted from the furnace, it fuses the two materials together. Figure 6.2 The brazing process using a furnace. As the material is left in the corner and is melted from the furnace, it fuses the two materials together. Figure 6.2 The brazing process using a furnace. As the material is left in the corner and is melted from the furnace, it fuses the two materials together. Figure 6.2 The brazing process using a furnace. As the material is left in the corner and is melted from the furnace, it fuses the two materials together. Figure 6.2 The brazing process using a furnace. As the material is left in the corner and is melted from the furnace, it fuses the two materials together. Figure 6.2 The brazing process using a furnace. As the material is left in the corner and is melted from the furnace, it fuses the two materials together. Figure 6.2 The brazing process using a furnace. As the material is left in the corner and is melted from the furnace, it fuses the two materials together. Figure 6.2 The brazing process using a furnace. As the material is left in the corner and is melted from the furnace, it fuses the two materials together. Figure 6.2 The brazing process using a furnace. As the material is left in the corner and is melted from the furnace, it fuses the two materials together. Figure 6.2 The brazing process using a furnace. As the material is left in the corner and is melted from the furnace, it fuses the two materials together. Figure 6.2 The brazing process using a furnace. As the material is left in the corner and is melted from the furnace, it fuses the two materials together. Figure 6.2 The brazing process using a furnace. As the material is left in the corner and is melted from the furnace, it fuses the two materials together.

Figure 6.4 The bolting process. Notice the threads within the end of the bolt. Figure 6.4 The bolting process. Notice the threads within the end of the bolt. Figure 6.4 The bolting process. Notice the threads within the end of the bolt. Figure 6.4 The bolting process. Notice the threads within the end of the bolt. Figure 6.4 The bolting process. Notice the threads within the end of the bolt. Figure 6.4 The bolting process. Notice the threads within the end of the bolt. Figure 6.4 The bolting process. Notice the threads within the end of the bolt. Figure 6.4 The bolting process. Notice the threads within the end of the bolt. Figure 6.4 The bolting process. Notice the threads within the end of the bolt. Figure 6.4 The bolting process. Notice the threads within the end of the bolt. Figure 6.4 The bolting process. Notice the threads within the end of the bolt. Figure 6.4 The bolting process. Notice the threads within the end of the bolt. Figure 6.4 The bolting process. Notice the threads within the end of the bolt. Figure 6.4 The bolting process. Notice the threads within the end of the bolt. Figure 6.4 The bolting process. Notice the threads within the end of the bolt. Figure 6.4 The bolting process. Notice the threads within the end of the bolt. Figure 6.4 The bolting process. Notice the threads within the end of the bolt.

Figure 6.3 The soldering process. mainly a diagram of the tip . very similar to brazingFigure 6.3 The soldering process. mainly a diagram of the tip . very similar to brazingFigure 6.3 The soldering process. mainly a diagram of the tip . very similar to brazingFigure 6.3 The soldering process. mainly a diagram of the tip . very similar to brazingFigure 6.3 The soldering process. mainly a diagram of the tip . very similar to brazingFigure 6.3 The soldering process. mainly a diagram of the tip . very similar to brazingFigure 6.3 The soldering process. mainly a diagram of the tip . very similar to brazingFigure 6.3 The soldering process. mainly a diagram of the tip . very similar to brazingFigure 6.3 The soldering process. mainly a diagram of the tip . very similar to brazingFigure 6.3 The soldering process. mainly a diagram of the tip . very similar to brazingFigure 6.3 The soldering process. mainly a diagram of the tip . very similar to brazingFigure 6.3 The soldering process. mainly a diagram of the tip . very similar to brazingFigure 6.3 The soldering process. mainly a diagram of the tip . very similar to brazingFigure 6.3 The soldering process. mainly a diagram of the tip . very similar to brazingFigure 6.3 The soldering process. mainly a diagram of the tip . very similar to brazingFigure 6.3 The soldering process. mainly a diagram of the tip . very similar to brazingFigure 6.3 The soldering process. mainly a diagram of the tip . very similar to brazing


Figure

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Figure 6.1 The main 3 different types of welding . (sequential order) TIG,MIG, Oxy acetylene


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Figure 4.2 Investment casting process diagram labelled and sequentially planned.

Figure 5.1 The thermoforming principle where the sheet of Thermosoftening polymer is pushed onto the vacuum forming pattern.

Figure 4.1 Sand casting . This is when the sand is all prepared and the molten metal is poured into the sprue.





















































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Figure 3.2 The formation of a sand mould.

Figure 3.3 The formation of a sand mould with altered grain structures caused using different materials.

Figure 3.4 The formation of a strong equiaxed grain structure within the metal.


Bibliography:https://www.livescience.com/48001-biomedical-engineering.html

http://www.irma-international.org/viewtitle/43282/

http://www.monash.edu.au/lls/llonline/writing/engineering/technical-report/4.xml

http://modelsofexcellence.eleducation.org/attributes-high-quality-work

https://www.utwente.nl/en/bms/wijsb/staff/brey/Publicaties_Brey/Brey_2009_Biomed_Engineering.pdf


http://www.bmecentral.com/a-history-of-biomedical-engineering/

http://content.time.com/time/specials/packages/article/0,28804,2029497_2030617,00.html

https://en.wikipedia.org/wiki/Artificial_heart

https://www.heartfoundation.org.au/images/uploads/publications/Artifical-hearts-information-sheet.pdf

http://science.howstuffworks.com/innovation/everyday-innovations/artificial-heart.htm

http://s.hswstatic.com/gif/artificial-heart-abiocor-hand.jpg

http://www.mayoclinic.org/-/media/kcms/gbs/patient-consumer/images/2013/11/15/17/38/my01077_my00361_im04277_mcdc7_lvadthu_jpg.jpg

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4295219/

http://www.exmetalworks.com/stainless_steel.htm

http://sciencing.com/advantages-disadvantages-biomaterials-8385559.html

http://www.aplusphysics.com/courses/honors/thermo/heat.html

http://www.yourarticlelibrary.com/metallurgy/press-forging-process-advantages-and-disadvantages/95518/

https://en.wikipedia.org/wiki/Gas_metal_arc_welding

https://www.embs.org/about-biomedical-engineering/our-physician-members/advances-in-biomedical-engineering/

https://en.wikipedia.org/wiki/Neural_engineering

https://www.sciencebuddies.org/Files/2084/5/Elec_primer-solder2.jpg

https://upload.wikimedia.org/wikipedia/en/thumb/7/7d/Furnace_Brazing.svg/300px-Furnace_Brazing.svg.png

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https://www.sciencebuddies.org/Files/2084/5/Elec_primer-solder2.jpg

https://en.wikipedia.org/wiki/Neural_engineering



https://en.wikipedia.org/wiki/Gas_metal_arc_welding



http://www.aplusphysics.com/courses/honors/thermo/heat.html

http://sciencing.com/advantages-disadvantages-biomaterials-8385559.html

http://www.exmetalworks.com/stainless_steel.htm

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4295219/



http://s.hswstatic.com/gif/artificial-heart-abiocor-hand.jpg

http://science.howstuffworks.com/innovation/everyday-innovations/artificial-heart.htm



https://en.wikipedia.org/wiki/Artificial_heart

http://content.time.com/time/specials/packages/article/0,28804,2029497_2030617,00.html

http://www.bmecentral.com/a-history-of-biomedical-engineering/




http://modelsofexcellence.eleducation.org/attributes-high-quality-work


http://www.irma-international.org/viewtitle/43282/

https://www.livescience.com/48001-biomedical-engineering.html


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