Lighten my car

[LITLNTUFF]

I sent my car in to get the rust cut out, have it stripped and resprayed. NOT CHEAP as we all know...
so much so thats its going to be cheaper for me to have the car lightened rather than have the panels repaired.

Does any one know what the strength and wheight saving properties of aluminum are? should I be considering a different material?

What else should I be taking into consideration? help

[DJJC]

As with anything motorsport - it depends one one major thing. How deep is your pocket.

if its rather shallow and the missus is saying that we DO have to eat this week (as if!), then i would simply stay with the steel body and rust proof it. take the weight out of the car somewhere else.

if you were considering buying a swimming pool this week and are prepared to push it back a while, aluminium as rather nice stuff, both mechanically and aesthetically. from memory, the desity of steel is around 7.4 g/cm^3, whereas aluminium come is at 2.8 g/cm^3 (or something like that...if i get excited ill look it up and post the actual numbers). but, aluminium is only around 2/5ths as strong as steel, which means that the strength to weight ratio is brought a little closer to steels favour. aluminium is still the better material. then consider that it doesnt rust as well. aluminium is nice stuff.

but then if you can seriously look at ivory backscratchers and reach for the wallet (i.e. filth rich) then go to carbon fiber. wonderfully light, tensilly strong and very stiff. and a lot of old school car people have said to me "its too stiff and its not right to build a car out of anything thats not a metal". to quiet those naysayers, look at the roof of a BMW M3 CSL...if that car isnt right, i want to be wrong.

then if you read the ivory backsratchers bit and thought "ivory, my bentley has a wheel made outta that!", then go for titanium. disgustingly expensive, quite dense (more dense than steel, but waaaaay stronger) and used in stuff like rockets and F1 and the like. you dont need to paint it (in fact, it should be a crime to paint such a wonderfully coloured material) and the car will have a fatigue life longer than you could think of. be prepared to spend more than 10 times the cost of the car to get it though.

[DJJC]

mediunm carbon steel density - 7.87 g/cm^3
yeild tensile strength - 380 MPa

aluminium (6061 T6) - 2.7 g/cm^3
yeild strength - 276MPa
(i believe that this is before heat treating, which will up the strength a little)

Hexel 12000 filament carbon fiber desity - 1.79 g/cm^3
ultimate tensite strength - 4280 MPa
(note, although very strong in tension, you have to layer it alot to make it stiff laterally and undercompression)


Titanium Ti-6Al-2Nb-1Ta-0.8Mo density - 4.48 g/cm^3
yeild strength tensile - 790MPa
Component Wt. %


Al 6
Mo 0.8
Nb 2
Ta 1
Ti 90