Hello Napier, this is the multi billion dollar question isn't it?
How do car manufacturers reduce weight without loosing strength or increasing costs.
I think carbon fibre or similar laminated materials have a lot of potential in the mass market one day but then you are looking at future production and assembly techniques rather than debating the pro's and con's of the materiel itself.
Because it is so time consuming to produce material this way it is expensive; will machine tool technology allow rapid cnc construction of carbon fibre panels anytime soon? Maybe.
Another drawback of carbon fibre is the complexity of trying to assemble the parts and the specialist equipment required. We have all seen the robot spot welding arms on the T.V. pinching body panels together at pre determined points, making a nice shower of sparks and within minutes they have created the monocoque. So how do you go from that to assembling carbon fibre panels? do they re-tool? is it possible to adapt what they have? are they going to have to invent the equipment to do it?
Will the speed of introduction and frequency of use depend on how many and how big future grants/incentive packages for low emissions vehicles are, as well as how keen the aerospace industry are to keep increasing the number of CF components on airliners? Maybe.
Engine blocks in Formula 1 are still cast aluminium, pistons are forged aluminium, rods are titanium, and crankshafts... are... steel, I believe, as are gears, drive shafts could be Ti by now but I suspect they could be steel still, so it is not necessarily the place to look for inspiration. Titanium torsion springs are a neat trick but not sure if one would last 100,000 miles if it was soft sprung enough to give a nice ride on a road car.
One of the biggest problems for future material in the mass market is steel is a very good material. There are many better materials in the bespoke world of F1, many have been tried and banned.
Steel is easy to form and weld, (important to insurance companies too, y'know accidents) a good strength/weight/cost ratio, and with a minor change in composition and possibly some heat treatment it can be a body panel, a wheel, a con-rod, a track-rod end a shock absorber. A piece that is machined with uniform properties throughout, i.e. in a soft state can be case hardened to give a very hard surface whilst being malleable in the middle to increase resistance to shock loading. Titanium is always hard and therefore a bastard to machine.
In fact the more I talk about it the more I think Wow! Steel, it's a wonder material! I would say you will see further increases in the quality of steel and changes in the types, stronger, thinner parts as this has less of a knock on effect on infrastructure like factories.
In some ways road cars may be showing the future materials of F1, when plastic technology reaches a certain point F1 may have to adopt parts similar to those on the humblest of motors. The number of plastic components on road cars is increasing each model cycle as the technology to make these parts stronger, more temperature resistant and to a greater accuracy is being driven by a very great variety of consumers in the wider marketplace (in other words there's so much money in plastics the people making it can't afford not develop it). It could be argued that plastic is currently less recyclable than metal and requires a fair amount of oil to produce, I don;t know the figures, shame on me.
Perhaps it is safe to say that for the time being the future of materials in the automotive industry revolves around steel, aluminium and probably more plastic. CF may be seen in greater quantities amongst niche cars, brand leaders such as the BMW M3 CSL & Audi R8 would be a prime examples, and due to it's attractive (or possibly just fashionable) finish when coated with clear laquer the perception that it it's use is becoming more widespread may far overshadow the actual increases that are happening.
speedsense said the future could lay in coatings and I think he could be onto something there.
I'm sure I saw a coating quite a while back that you can put on say aluminium (just as an example) which then allow it to be used as the outer race of a steel balled bearing, now that has potential but it's not really the aluminium that has made that possible. it may have been a Poetons coating.
Some other firms to Google are Sulzer, Balzers.
There was a great article on here a few weeks ago about a coating:
http://www.f1technical.net/features/12397
This is not a very well put together post, I know it rambles because im a bit tired but hopefully some food for thought.