In the 1930s some American cars (Nash?) had stainless bodies. Why didn't it catch on? Even the extra expense of the stainess steel must be less than has been spent on achieving decent rust protection on normal steel. I imagine a stainless body with a low drag coefficient could be upgraded with better engines etc. as the years went on, rather than buying a new car.
Chris
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Aluminium?? or aloominum if you're a septic......
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De Loreans weren't successful in bare s/steel as they apparently showed every finger mark.
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Well, if planned obsolescense fails to work you might as well try corrosion.
In Germany in 1948 we had fun with the vast pre- production transport hailed by AFN as the "great aluminum freightship".
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Chris
Probably cost is the key issue. Basic material cost is higher, fabrication is more expensive, and it still needs painting. As has been mentioned, a number of DeLoreans were painted because they looked awful with finger prints etc after a while. You've got to use the right stainless too. The cheaper stainless steels will rust, especially when exposed to chlorides. Corrosion can also be a problem at welded joints. Given how long modern mild steel plus some galvanising plus paint lasts, it's not going to be a big selling point, even for those who like to hang onto their cars.
The key reason for this is that whilst it's commonly said that components could keep being changed, eventually reliability would suffer, or owners would tire of the style, and, importantly, require the latest safety innovations. Imagine you bought your everlasting stainless car 20 or more years ago. You might by now fancy the latest suspension to give it modern levels of roadholding and handling, current standards of crash protection design, improved brakes and ABS, aircon, airbags etc all of which would be prohibitively expensive, or more likely impossible, to retrofit and on that basis a modern mild steel body will last more than long enough. I'm not advocating a throwaway approach, but things really have moved on in terms of what current cars offer.
Regards
john
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John S is absolutely right in that the issue of cost and required obscolescence is the key to this.
Its quite possible to design and build in special stainless with high strength very resistant to chloride attack thus things can be built with significant weight savings.
A guy consulted me on a few occasions on a design he was doing to build an entire sailing yacht out of duplex stainless to take advantage of the high strength. The problem I could see was when he was in some godforsaken place t'other side of the world and wanted to do a weld repair, they would probably have the kit to do a low alloy or mild steel weld but not a satisfactory stainless one, though that is getting better. In summary it was a good concept for something like a yacht that, if done right, will last a lifetime and save weight. But hate to think of situation if we were running around in cars designed 25 years ago?
Just think if I had had that Mars Bar Viva made in stainless.... hmmm,........no its too early for horror stories, want to sleep tonight.
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Chris
There was an article in I think "OEM Design" magazine this month about stainless in cars. You are going to see more of it. Its main benifits are that its strength increases when its deformed, as in a crash and that in the right grades it won't corrode to quickly.
Duplex stainless steels are far more corrosion resistant than nomal types of stainless but do cost more. I specified a new boiler hotwell tank in 1999 to be made in 2304 duplex stainless due to its superior hot temp and chlorine resistance.
Stainless will, I think be used in sub frame parts first and in the interior sections of the body rather than on the outside. Its hard to paint, or at least so the paint stays on for any length of time, and DeLorean did have some sort of budget to keep to.
Bill
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Worth remembering that stainless rusts anaerobically,or rather corrodes,it is also susceptible to electrolytic decay when other metals are present.
It is also heavy,expensive,and a swine to work.
Years ago I was taught that there were no bad materials,only bad applications...
we can easily make lightweight,cheap and adequately corrosion resistent structures,we can make them very strong and with excellent deformation characteristics.
Or rather the aero-engineers can,auto engineers apparently havent a clue.
If they spent less time farting about with new door panel designs and competing to see how heavy they can make seats we might see some progress.
In fact,what will happen is that the upcoming CAFE regulations will force them to.
Unless they just stop making those strange mobile garages with big chunky tyres,of course...
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