Automotive Materials Info Needed....

danza

danza

danza

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Hi all,

I'm writing an assignment about materials used in the automotive industry, and need to select and describe about a dozen materials and why they are suitable for the job. I basically need a reference that I can work from as although I know a fair bit about what the materials actually are, I'm not so sure on the reasons they are chosen etc. and need a little guidance on this.

I could probably wing it on what I already know, but I want a little more depth to my assignment than 'aluminium is used for cylider heads because it is light and corrosion resistant'.

Are there any really useful sites out there (I can't find them)? I'm not doing an automotive course, it's just that the materials engineering section of my Manufacturing Engineering HND ties in with automotive engineering (they're trying to kill two birds with one stone and group us all together for ME).

Cheers!
 
Cover Plastics, steel and the different tensile strength steels in a monocoque chassis to tune its energy absorption characteristics. Aluminium is also being used to reduce weight and reduce CO2 emissions, new Range Rover will be 500kg ligher from the use of aluminium.

The cylinder head one for example is thats its also a lot easier to cast and then machine to the desired shape.

Cant really think of where you would look, google stuff like nylon 66 for why its used in things like intake manifolds. Also a lot of materials are now selected on there recylablility due to the end of life legislation rather than purely performance/cost.
 
Carbon composites is a good topic to cover. All F1 props are made from this as well as the pressure vessels. Got a friend who is in charge of the motorsport division for a big composite supplier, will ask if he has any useful info he can pass on.
 
Indeed it does, good suggestion, I just wanted to rant about carbon in cars :D Definatley include that one in your report.

The longer and heavier the prop shaft, the lower its resonant frequency and the more likely it is to cause vibration problems when the vehicle is travelling at high speed. For this reason, the prop shaft is usually split into two sections connected by a centre bearing. But this kind of construction invites extra weight, the enemy of good sports car design. Furthermore, attaching the centre bearing to the floor of the car encourages seepage of prop shaft vibration.
To overcome this problem, manual transmission models employ a lightweight one-piece prop shaft composed of steel, carbon fibre and high-strength plastic (AT cars use a steel prop shaft), and the transmission and differential are mounted on a rigid Power Plant Frame (PPF). This arrangement not only weighs about five kilograms less than a conventional two-piece prop shaft, it also eliminates the need to attach the prop shaft to the vehicle floor. The result is a substantial reduction in NVH levels.
Additionally, the PPF is equipped with dynamic dampers that control resonance and have a closed section structure, improving the direct, linear acceleration feel in response to accelerator pedal inputs
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Like I was saying about carbon composite, it does get used in road cars....I had a carbon prop on my scoob (obviously didnt pay the £1200 it cost) and you could definitely feel the difference.
 
panthro said:
Like I was saying about carbon composite, it does get used in road cars....I had a carbon prop on my scoob (obviously didnt pay the £1200 it cost) and you could definitely feel the difference.
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Cost bit is exactly why most OEM's dont use them!

A WRC car was once a road car, its not actually a road car though is it. This is an engineering course, unless its aerospace, cost will always be a big consideration.
 
CFRP: light, stiff, strong, eye-wateringly expensive. Used for body panels and structural elements depending on application. If the car is rebuilt every race (i.e. F1) then more exotic materials can be used. This is coming down in price, too, as techniques get more sophisticated. Cool things can be done with structural members through using piezo-electrics to determine damage to such components.

Aluminium alloys: going out of vogue in motorsport to a degree, because CFRP is lighter and can be stronger. It's reasonably strong and pretty light. It can be used for structural elements, too (think Jaguar XJ, Lotus Elise, Audi A2/8. It's quite popular in production suspension compnonents, now, too. Corrosion resistant by virtue of their oxide layer.

Titanium alloys: very strong alloys (depending on alloy type and composition). and pretty light, too. Rubbish wear resistance means they have to be treated before being used in load-bearing applications, but can be used for structural elements as required. Generally not, because it's so expensive and difficult to work with. Corrosion resistant by virtue of their oxide layer.

Magnesium alloys: rubbish wear resistance, not particularly stiff/strong, but very, very light. Engine blocks can actually be made out of them assuming they're appropriately sleeved. Other mechanical components are also made from Mg alloys, but this is also really expensive. F1 wheels used to be made (last time I looked around 3/4 years ago) from magnesium alloy... corrosion resistant by virtue of their oxide layer.

Steel (stainless, too): very strong, can be very hard. Very heavy. Very cheap in most instances. very expensive in others (not quite Ti-alloy levels, though). It depends on how clever the fabricator is. Can be very corrosion resistant: can also be readily attacked in air.

Silicon carbide: composites 'tis was brakes can be made from. Potentially cobalt-base matrix with large amounts of SiC particulate in suspension. Ridiculously hard and durable, but very brittle. These probably won't warp or anything under constant braking. If you're very rich, you could make them out of carbon composite (fix SiC in carbon-based resin - i.e. some polymer - and heat to a high temperature.. the result will be a carbon block with SiC in 'solution' as such. Very brittle, however.).

There are also any other number of wierd and wonderful materials used within the automotive industry, for instance Honda have been known to play with aluminimum engine blocks with ceramic fibre reinforcement for strength. Surface treatments are also very important to consider as unremarkable base materials can be made to exhibit remarkable properties through the correct application of surface treatments (look up PVD/CVD, titanium nitride, amorphous carbon/diamond, MoS2, titanium oxide, carburising/nitriding, ion beam nitriding, anodising... the list goes on).

Drop me an email if you have any questions: I did my PhD in surface engineering and have done a huge amount of research on surface engineering in motorsport.
 
Jonnycoupe said:
Cost bit is exactly why most OEM's dont use them!

A WRC car was once a road car, its not actually a road car though is it. This is an engineering course, unless its aerospace, cost will always be a big consideration.
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To be fair, OP doesnt mention anywhere about cost or what applications it is used for in the automotive industry.
 
Manufacturing engineering would tend to bias towards mass production rather than bespoke fabrications. Hence by guidance towards those types of materials with more quantifiable reasons on the selection rather than the more petrolhead reasons you will find in motorsport/low volume.

Its certainly where I'd focus my efforts anyway.
 
Jonnycoupe said:
Manufacturing engineering would tend to bias towards mass production rather than bespoke fabrications. Hence by guidance towards those types of materials with more quantifiable reasons on the selection rather than the more petrolhead reasons you will find in motorsport/low volume.

Its certainly where I'd focus my efforts anyway.
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Yeah, it would help if I read the last paragraph more carefully, I assumed he was doing automotive engineering, not manufacturing eng.
 
Blimey, zero replies last time I looked!

You've certainly added fuel to the fire, and things I wouldn't otherwise have thought of.

I think I might be taking this assignment too seriously though - my lecturer told us what he expects from us, and it isn't very in depth.

Hell to it though, I'll go all guns ablazin' and teach myself some things about automotive materials, and send my lecturer to sleep at the same time.

Cheers!
 
I have a whole booklet on this.

About 45 Auto Engineer students from my course had to do a material each, then write 2pages on its application in the industry. I think I had ceramics, so i just wrote about turbos :D
 
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