997 2005-2012 911 C2, C2S, C4, C4S, GTS, Targa and Cabriolet Model Discussion.
Sponsored by:
Sponsored by: CARiD

Wheel Material

Thread Tools
 
Rate Thread
 
Old Jul 15, 2007 | 02:10 PM
  #1  
hozer's Avatar
Thread Starter
|
Banned
Joined: Jun 2007
Posts: 101
From: Dallas
Rep Power: 23
hozer is infamous around these parts
Wheel Material

There is a lot of talk of "soft" and "hard" wheels and of course their associated weight. I was looking at the Kinesis F110 wheels since they look great and found this....

Kinesis F110 wheels are forged of 6061-T6 aircraft quality aluminum making them strong yet very lightweight.

I dont really know much about wheel materials, but I am a structural engineer working the aerospace industry. 6061-T6 is a pretty poor material structurally and about the only thing we use it for is brackets since its pretty easy to bend in its heat treated condition. Evenso...most newer airplanes are going for better aluminum for even brackets. I have never seen 6061-T6 used for any primary structure, its just very weak.

On the other hand, 7075-T6 and 2024-T4 are "real" "aircraft quality" alloys (and associated heat treats). This is what has generally been used for wings, bulkheads,frames, skins.

So if 6061-T6 is good for a wheel and is "aircraft quality", then what the heck is the back stuff? I cannot think of anything too much worse than 6061 off the top of my head, but I am sure there are some worse alums.

Of course the process will make it different (i.e. cast versus forged), but still 6061 just isnt that great.

For ref, 6061-T6 has a Ftu of 44ksi die forged while 7075-T6 has an Ftu of 78ksi die forged...nearly 80% stronger.

mil-hdbk-5 provides material data and is public domain.

 
Old Jul 15, 2007 | 02:32 PM
  #2  
dndodd's Avatar
Registered User
Joined: Nov 2006
Posts: 546
From: Birmingham, AL
Rep Power: 41
dndodd is infamous around these parts
Interesting. So in your opinion who makes a good qaulity lite weight wheel mfg from good aircraft alum?
 
Old Jul 15, 2007 | 03:00 PM
  #3  
hozer's Avatar
Thread Starter
|
Banned
Joined: Jun 2007
Posts: 101
From: Dallas
Rep Power: 23
hozer is infamous around these parts
There may be several reasons of practical purposes. Yes, 6061-T6 had decent ductility and this will help to absorb energy beyond the elastic limit (the wheel is essentially ruined at this point) in the event of a hard bump, etc.

I suspect cost and availability may be good reasons they dont use better alloys either.

Casting/forging probably doesnt change the strength of the material too much, but it may help at the part level due to potential porosity and added brittleness of the casting (getting a little out of my domain though).

I guess what surprises me (and I suppose it shouldnt) is that they call 6061-T6 an "aircraft aluminum". Heck, if you are going to say that than any alum is an aircraft aluminum...you can probably find many different alloys for nonstructural applications. Its not a bad material and I have used it a lot in prototyping because its cheap and easily formable...but by no means is ever used on anything truly structural (unless for some reason a higher ductility is needed). Never heard of that situation, but it could exist.

I am not too familiar with auto materials and usage, but aerospace is highly concerned with weight. So more money can be spent on better material to achieve lower weights. I think right now good alum is in shortage because of programs like the Boeing 787 and Lockheed Joint Strike Fighter.
 

Last edited by hozer; Jul 15, 2007 at 03:03 PM.
Old Jul 15, 2007 | 04:45 PM
  #4  
hozer's Avatar
Thread Starter
|
Banned
Joined: Jun 2007
Posts: 101
From: Dallas
Rep Power: 23
hozer is infamous around these parts
Haha...I doubt it. This is all very common knowledge if you work in the aerospace business. I really doubt I know more than the guys who make the wheels. I think there must be financial/mnfr/etc factors to consider that make true aerospace allows unpractical. Although, I wonder if true high end wheels would warrant stronger alloys?
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Zero911
997 Turbo / GT2
4
Aug 24, 2015 06:51 PM
plenum
991
2
Aug 21, 2015 10:02 AM
vividracing
997 Turbo / GT2
8
Aug 21, 2015 06:34 AM
ModBargains
Tesla Motors Vendor Classifieds
0
Aug 20, 2015 12:28 PM



You have already rated this thread Rating: Thread Rating: 0 votes,  average.


All times are GMT -6. The time now is 06:56 AM.