Alloys are less dense, so the wheels are lighter, and thus have a lower moment of intertia so are fitted to racing cars. Hence why they are essential on a 1.1 Nova.
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Alloys fitted to standard cars are not significantly lighter than steels(in some cases are heavier)-what you see on rally and racing cars are alloys with a high percentage of magnesium.
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because steel wheels are ugly, plastic hubcaps are naff, alloys aint and becuase we have the moeny to pay for what we want.
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Steel wheels aren't always or necessarily ugly AE, they just usually are these days. Everything else you say is right though.
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because steel wheels are ugly
Why should stainless steel wheels be ugly?
plastic hubcaps are naff
..and why should stainless wheels have "hubcaps"?
alloys aint
They are once the silver paint on 'em has been scratched a bit, and bubbled..
and becuase we have the moeny to pay for what we want.
So why not use a superior material?
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I have to agree with FT that once even slightly scraped, alloys start to look moth-eaten and dissolve into white powder.
Actually there aren't any scrape-proof wheels. Perhaps a replaceable throwaway-price plastic rim-guard can be devised.
I have to say that hearing an alloy wheel scraping a kerb (how many here are going to claim they never have?) makes the heart sink much further than the jolly crackle of a carp silver plastic wheel trim getting a richly-deserved drubbing... but absolutely nothing beats the horror of pinching a tyre-wall against a sharp projecting kerbstone...
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>>So why not use a superior material?
Materials choice is not so straightforward, and in this application stainless is not at all superior.
The type of stainless that might find favour in wheel applications is Austenitic stainless steel - this is because it has some plasticity, and the wheel would deform slightly upon kerb impacts, rather than break suddenly.
The problem is that Austenitic stainless steel is prone to stress corrosion cracking, especially in a chloride rich environment, so, the stainless wheels might only be suitable in Summer!, and would have to be put away before the first gritting truck hit the streets.
The marketing people have won people round to the idea of fitting naff alloy wheels by hinting that alloy wheels are the performance option (despite in truth being no such thing). How would expensive, Summer only, stainless wheels be sold?
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The problem is that Austenitic stainless steel is prone to stress corrosion cracking especially in a chloride rich environment
(snip)The marketing people have won people round to the idea of fitting naff alloy wheels
So, can you tell me whether the light alloy used for car wheels is more or less resistant to stress corrosion cracking than is Austenitic stainless, or is it about the same? What about other forms of stainless steel?
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So can you tell me whether the light alloy used for car wheels is more or less resistant to stress corrosion cracking than is Austenitic stainless or is it about the same? What about other forms of stainless steel?
Yes I can, and so could you were you to try googling scc.
www.azom.com/details.asp?articleid=102
Why do you imagine that you have suddenly managed - whilst sitting in front of your computer with nothing better to do - to think of a new materials solution to an engineering problem that no engineer has ever come up with?
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>> So can you tell me whether the light alloy used for car wheels is >> more or less resistant to stress corrosion cracking than is Austenitic >> stainless or is it about the same?
Yes I can and so could you were you to try googling scc. www.azom.com/details.asp?articleid=102
The contents of that link does not mention the light alloy used for car wheels.
So, is it more, or less, resistant? I haven't yet read NC's explanation, but I suspect he'll let you off the hook.
Why do you imagine that you have suddenly managed - whilst sitting in front of your computer with nothing better to do - to think of a new materials solution to an engineering problem that no engineer has ever come up with?
I made no such claim. You seem a bit tetchy.
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NC did not answer the question. I'd love to know what it is - so - over to you!
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>>So, can you tell me whether the light alloy used for car wheels is more or less resistant to stress corrosion cracking
Off the top of my head, no - I'm sure there are many different types and grades of alloy have been used over the years. What I can say is that the grade of alloy which I make a great deal of use of in my work has *no* recorded instances of stress corrosion cracking.
Stress corrosion cracking is an odd phenomenon, and can easily catch people out - for example, Titanium, cleaned with methanol is prone to SCC, but, use another alcoholto clean the surface, and you're OK.
The real danger of SCC is that the corrosion isn't like normal rust and rot, in that it happens between grain boundaries within the metal - the outer surface can look OK to the naked eye.
The problem with the other grades of SS is that they are all more brittle, and hence are subject to simple fracture during an overload. Perhaps there is a compromise between grades which are subject to SCC, and grades which have no plastic behaviour, but, it wouldn't be cheap, and it wouldn't be light. If you're spending serious money, why not use a good, light, magnesium alloy.
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(in answer to NC, in case the threading isn't obvious)
Well, you see, the issue is that should "normal" car wheel alloys be at least as susceptible to SCC as is composition X of stainless, then the use of X would, at first sight, be quite acceptable. Also, without knowing about the effects of SCC, if any, on other alloys, such as the sort you mention, it's again very hard to know which is acceptable.
I actually suspect that there're reasons, other than metallurgical ones, why S/S isn't currently used in this application. A quick Google suggests that use of this material is being explored, BTW.
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It's simply that stainless isn't a superior material in this application. It offers no weight benefit, and it is higher cost than a mild steel rim with a plastic whel trim.
There's no performance gain, and a cost hit - no wonder they aren't used.
Added to that is the metallurgical problem, the problem in making the wheels look nice - it's much harder to make stainless (or any steel) look nice than it is aluminium alloy - aluminium alloy cuts really easily, and can be turned to a good polishable finish with any great fuss.
I'm fairly sure (although if I were actually specifying the material in a real application, I would do quite a bit of research work) that the alloy used for wheels isn't subject to SCC in any serious way - the grades of alloy that are susceptible to SCC are a bit too expensive for car use.
>>A quick Google suggests that use of this material is being explored, BTW.
Doubtlessly by a stainless steel manufacturer's lobby group - these types are always cropping up suggesting inappropriate material uses.
FT - stainless for car wheels is a non-starter. (I suppose there could be silly niche applications, akin to expensive "pilots" watches which are no more accurate than a £2 quartz watch!)
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It's simply that stainless (..) offers no weight benefit and it is higher cost than a mild steel rim with a plastic whel trim.
From previous posts, it would seem that an alloy wheel for a car offers no benefit compared to a mild steel wheel. The extra cost of S/S (above mild steel, below "alloy") ought to be trivial.
There's no performance gain and a cost hit - no wonder they aren't used.
I am not wondering merely about performance - I'm not sure how that particular thought came in. There's appearance, as in the OP - polished S/S. You realise that your statement above, about "no performance gain, and a cost hit", applied to the vast majority of alloy wheels fitted to cars now, compared to mild steel wheels, is applicable? Yet there are lots and lots of examples of alloy wheels in production right now!
Added to that is the metallurgical problem the problem in making the wheels look nice
Oh, come on. If it can be done for saucepans, I'm sure it can be done for car wheels.
I'm fairly sure (although if I were actually specifying the material in a real application I would do quite a bit of research work) that the alloy used for wheels isn't subject to SCC in any serious way
I might look into that, a little. How do you justify that statement, given your previous posts on SCC and materials used to clean metals? Perhaps stainless, in one guise or another, would be similar to light alloy in this respect. The answer is not plain at all. I wonder whether Mapmaker will find it out. All I've seen so far is - no real answer.
>>A quick Google suggests that use of this material is being explored BTW. Doubtlessly by a stainless steel manufacturer's lobby group
It was some sort of Hitalian concern who make wheels, AFAIR. Different techniques of forming and putting together wheels.
FT - stainless for car wheels is a non-starter.
This sort of statement, backed up by nothing real, won't really do at all.
Have you a background involving formal metallurgical studies, BTW? OT, but interestin to know who I'm talking to!
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FT - you are on the wrong track.
If SS wheels were such a good idea, we wouls already have seen more of them - perhaps at least on the Delorean
>>If it can be done for saucepans, I'm sure it can be done for car wheels.
There's no similarity between making pans and making car wheels.
>>How do you justify that statement,...
Simple - cars with alloy wheels don't seem to suffer from SCC. General corrosion, yes, buckling and kerbing damage, yes. I haven't, in my experience, seen any evidence of SCC. That level of evidence is sufficient IMO for a car forum debate; it's just, I would be so cavalier if I were making a career critical material specification.
>>but interestin to know who I'm talking to!
Sorry, but that's not a conversation I'm going to indulge you in.
>>won't really do at all.
It's all you're getting!
;-)
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cars with alloy wheels don't seem to suffer from SCC. General corrosion yes buckling and kerbing damage yes. I haven't in my experience seen any evidence of SCC. That level of evidence is sufficient IMO for a car forum debate;
No. You've said that Stainless wheels are not used because of SCC. You have said that you have seen no evidence that alloy wheels suffer from SCC. To form the conclusion that you do - that S/S wheels are not used because of SCC, because yoy think that "alloy" ones don't, without offering up any real evidence at all, is, IMO, uncharacteristic.
>> >>but interestin to know who I'm talking to!Sorry but that's not a conversation I'm going to indulge you in.
So you have no background in metallurgy. At least I have some, if only briefly, a long time ago. Now the debate falls back on MM.
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Despite your childish attempts to goad, I will answer two points;
>>without offering up any real evidence at all
I have said that the grades of aluminium alloy I use in my work do not succumb to SCC. Therefore aluminium alloy can be made to avoid SCC.
If grades of aluminium alloy which were known to be subject to SCC were used by a manufacturer, that would be negligent, and the company would be leaving itself open. Car makers are far too cautious and conservative for that. Consider just how recently Japanese manufacturers have even begun to think about using aluminium for clutch slave cylinders.
The problem of SCC in the common austenitic grade of stainless steel is a really well known problem. No responsible manufacturer would be able to use the material in a structural capacity on roads which are known to be salted without some serious development work. The choices would either be; to use a more suitable, more expensive grade, perhaps a duplex?, or to paint the stainless steel to protect it, thus obviating one of the reasons for using stainless in the first place.
>>So you have no background in metallurgy.
My refusal to bandy qualifications and experience allows you to draw no conclusion at all. That you do choose to attempt to draw a conclusion about me tells us all a great deal.
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There's no similarity between making pans and making car wheels.
Apart from manufacturing process, finish, metal, working environment - apart from industrial pans, processes, a rather more extreme environment... wet, salt, pressure, temperature, stress, manufacturing issues... oh, actually there are quite a few similarities. Ho hum.
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how many here are going to claim they never have?
I've never kerbed an alloy wheel, and I've had alloys for the last 22 years. However, since 1981 when my kerbside parked car was severely damaged by a passing car, I've only parked on the road once in a blue moon.
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I suppose I must believe you escargot. What is your secret?
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I suppose I must believe you escargot. What is your secret?
Simple. Don't park on the road!
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Aren't the rims on the Bugatti Veyron made of stainless steel?
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I prefer steel wheels (never owned a car with alloys), entirely down to cost and practicality!
1) Standard car models fitted with steel wheels are usually an insurance group lower than equivalent models fitted with alloys.
2) Steel wheels are less likely to get nicked (see point 1).
3) Steel wheels should last the life of the vehicle (assuming you manage to avoid the potholes)
4) They are painted black so you really on't have to bother cleaning them, just a quick wipe over of the wheel trim and job done. Alloys take ages to clean.
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To answer Chrome's message.
You can add:
5) Standard steel wheels don't normally use low profile tyres so the car rides better.
6) Here in Germany where everyone has 2 sets of wheels and tyres for summer and winter use it makes sense to have steel wheels in the winter to avoid your expensive alloys suffering grit damage.
When I bought my Mercedes W124 Coupe I originally wanted to get a set of cheapo steel wheels for winter use. Fortunately I did some background research before wildly bidding on eBay and discovered to my horror that I cannot fit steel wheels to my particular model.
Further research indicated this was because the brakes on later 6 cylinder W124 Coupes were enlarged and there are no known steel wheels which will clear them. I also discovered that, in addition to this, the offset of the wheel is critical on this particular model otherwise the tyres will foul the wheel arches.
eBayers clearly know their stuff because finding a set of alloys with the correct offset was expensive and time consuming. All the more galling because, as I said, I only wanted a cheap set of wheels to get me through the winter.
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I have to say that my current car, a MK 5 Golf (soon to be discontinued), was my first car to have alloys as I thought that they would be an answer to my prayers, including being easier to handle when removed but nothing could be further from the truth.
They look 'cool' but are too easily damaged and are a damned nuisance to keep clean.
I do wish that any further new car I buy eg. Golf MK 6 and of a suitably high spec. could be ordered with standard steel wheels and simple push-on plastic wheel trims!
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Chrome. I couldn't agree wit you more, but I think you missed one important point.
Steel wheels usually carry a higher profile tyre, and therefore are likely to give a more comfortable ride with better economy (I'm getting old).
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In the 'old days', a car wasn't a proper car without a set of wolfrace alloys - really set a car orf like ... I owned some 'cosmics' once and had em blasted by a mobile alloy wheel geezer - they came up a treat.
*Light* alloy wheels affect the unsprung weight, so I read once upon a time in a car mag. and hence improve a cars ride.
Dog.
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Steel can be beautiful too! Ford used to do some pretty tasty looking steel wheels fitted to Capris & Escort Mexicos, and Vauxhall did some nice black star pattern ones fitted to mid-80's Novas / Astras, the white steel wheels fitted to Land Rover 90/110's are classics......
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I once had some genuine Minilite mag alloys on a car I bought and they were really light. They were worth more than the old Escort GT they were on!
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How about alloy wheels with plastic covers.......as in the Prius - what's that all about ?
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Aerodynamics? Citroen did it better on the BX using Steel wheels and flat wheel trims!
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These would enhance any car, but they need to be lacquered to keep them looking nice!
~ www.wolfrace.com/
bad dog.
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There have also been some nice looking hubcaps, Lotus Cortinas / Escorts and those fitted to the first V6 Cavs spring to mind.
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The Rostyle steels fitted to some '80s Fords looked pretty good. If you dinged one on a kerb you could fix it with a rubber hammer and a tin of Humbrol.
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230292713884
The above is an item number from an electronic auction site and is for a stainlees outer rim for a Jag BBS split rim alloy
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stainlees outer rim for a Jag BBS split rim alloy
Yes, it's a trim, not a structural part of the wheel. Stainless is excellent for trims.
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The above is an item number from an electronic auction site and is for a stainlees outer rim for a Jag BBS split rim alloy
That looks like what I think Ford used to call an "embellisher" - purely cosmetic trim!
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Why not plastic wheels of some sort? Do we have the technology and materials? Or do the manufacturers make too much profit from alloys?
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I did once own a bike for a few months with carbon fibre wheels.
Great care had to be taken though as they were around a grand each - and did not bend, but shatter.
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