Aluminium alloy Al7075

[Gaurav]

I am looking for aluminium alloy Al 7075 grade for the fabrication of uprights.Since the alloy is not available in my country,I am searching for its dealer. Please suggest some dealers of the same and help me out.

[Gaurav]

I am looking for aluminium alloy Al 7075 grade for the fabrication of uprights.Since the alloy is not available in my country,I am searching for its dealer. Please suggest some dealers of the same and help me out.

[Mi_Ko]

Hi Gaurav

I know what you mean with "is not available in my country"! We also have some troubles finding parts for the car.

Try AircraftSpruce and The Chassis Shop. I could also reccomend you impol.si, an aluminium manufacturer in Slovenia, but I doubt they'll send you to India.

Good luck.

PS.
Hope we'll see you in Leicester 04!

2002/03 University of MARIBOR - Team Member

[ben]

At this point I suspect Mr Clark will chip in and question making uprights out of aluminium at all. I would tend to agree from a stiffness point of view.

If you're set on making them out of Al though bear in mind that 7075 is very expensive. Surely if you're having trouble sourcing material a fabricated mild steel upright might be a better solution?

Ben

University of Birmingham
www.ubracing.co.uk (http://www.ubracing.co.uk)

[Frank]

Companies that repair aircraft landing gear will know who the most reputable and reliable supplier is.

Ring up a local aircraft repairer.

You might find a supply of 2024 alloy in T3 or T351 temper (this is almost as strong, better fatigue properties at elevated temperatures, higher fracture toughness, easier to machine, but has less desirable corrosion resistance).

They might also use British Aerospace classifications.

QQ-A-200/3 2024 Bar

QQ-A-250/4 2024 Plate

QQ-A-250/5 2024 Alclad Plate

QQ-A-200/11 7075 Bar

QQ-A-250/12 7075 Plate

QQ-A-250/13 7075 Alclad Plate

Personally I don't think 7075 or 2024 is really much more expensive than the more common 2011, 2030, 6060, or 6061 alloys, but it is far more difficult to source.

There is a good list of specs in this PDF

http://www.corusgroup-koblenz.com/english/company/brochures/pdf/AC_technical_feb_2003_6.pdf

Why don't you contact these guys..

AGM (Integrated Material Management)
Hindustan Aeronautics Limited
15/1 Cubbon Road
Bangalore 560 001, India

Tel : 91 - 080 - 2860292
Fax : 91 - 080 - 2867234

[This message was edited by Frank on February 19, 2004 at 09:24 AM.]

[Didier Beaudoin]

7075-t6 is more expensive, I'm positive about that.

One thing you should also bear in mind is that 7075 is really harder to weld. If you need to weld, I'd suggest 6061-T6.

Didier Beaudoin
Team Leader -
École Nationale d'Aérotechnique

[PatClarke]

Ben,
http://fsae.com/groupee_common/emoticons/icon_wink.gif
PDR

I'd rather have a bottle in front of me than a frontal lobotomy

[zorr0]

Matweb:

E_4130=29700 ksi

E_7075-T6=10400 ksi

Rho_4130=.284 lb/in.^3

Rho_7075-T6=.102 lb/in.^3

E4130/rho_4130=104577 2.6 whopping % stiffer.

E7075-T6/rho_7075-T6=101961

The alloy you use and its condition makes a huge impact. 6061 in its as welded state is not suitable for flatware.

7075 is not considered weldable.



http://www.auburn.edu/~zornmat/eagleside.jpg

http://www.auburn.edu/~zornmat/pics/img_0399.jpg]

[PSU Racing]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>At this point I suspect Mr Clark will chip in and question making uprights out of aluminium at all. I would tend to agree from a stiffness point of view <HR></BLOCKQUOTE>

Ben, here are a few material properties from Matweb.com

Aluminum, 7075-T651:
Modulus of Elasticity / density = 25.51 Gpa cc/g
Yield Strength = 501 Mpa

Steel, 4130 annealed:
Modulus of Elasticity / density = 26.11 Gpa cc/g
Yield Strength = 460 Mpa

Titanium, Grade 5 annealed:
Modulus of Elasticity / density = 25.73 Gpa cc/g
Yield Strength = 830 Mpa

As you can see the stiffness to weight ratio of all the metals are within 5% of each other. So using these metals you can't make a part stiffer and lighter. But what you can do is increase a parts yield safety factor with the proper material selection.

Choose your materials wisely!

Garth Frederick
2004 Project Engineer
PSU Racing

1996-2002 Georgia Tech Motorsports Alumni

[Jackson]

Be careful about welding aluminum!

If 6061 is welded it needs to be COMPLETELY RE HEAT TREATED.

After welding, 6061 returns to its "O" or un heat treated state, which has a yield strength of 8 ksi or 55 MPa -- IE it is worse than pot metal.

That has burned us in the past.

As for suppliers, look up FORTAL on ebay-- it is an alloy essentially the same as 7075-T651 but the composition is owned by a die manufacurer -- there are lots of decent size "scraps" for sale. We have got quite a bit of material from ebay, but of course we are stateside. Of course we have an endless supply of super cheap 2024T351 and 7050T6 from Boeing surplus as well...

Brian
Washington State U FSAE

[Denny Trimble]

Yeah, Boeing Surplus is great if you have a good band saw to make parts out of large brick shapes http://fsae.com/groupee_common/emoticons/icon_smile.gif

Sunshine Metals (www.sunshinemetals.com (http://www.sunshinemetals.com)) has the best price for aluminum plate, bar, etc. that we've found yet. They have distributors across the country I believe.

University of Washington Formula SAE ('98, '99, '03, '04)

[Jackson]

What do you make your parts out of Denny?
Shavings? http://fsae.com/groupee_common/emoticons/icon_smile.gif

Usually material does come in brick type shapes.

I guess we are just used to scrap. None of this 6 square edged plate stuff! Although BS does have some nice 2" 2024T351 plate in 2x4' sheets pretty regularly.

Hard to beat $0.87/lb for 7000 series aluminum!

Brian
WSU FSAE

[Sam]

haven't read the thread properly but why don't you try 2024 T3 - T4 or somehting dude. and who is the clown that wants to weld ally uprights in there somewhere... duuuuude.... http://fsae.com/groupee_common/emoticons/icon_confused.gif

Sam Graham
Random Stooge 2004
UQ Racing

[Denny Trimble]

Yeah, I've made plenty of parts out of big bricks - and I mean little stuff out of really big stuff. I'm just lazy in the shop and I like starting with a nice flat plate, instead of spending 4 hours getting to that step.

University of Washington Formula SAE ('98, '99, '03, '04)

[ben]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by PSU Racing:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>At this point I suspect Mr Clark will chip in and question making uprights out of aluminium at all. I would tend to agree from a stiffness point of view <HR></BLOCKQUOTE>

Ben, here are a few material properties from Matweb.com

Aluminum, 7075-T651:
Modulus of Elasticity / density = 25.51 Gpa cc/g
Yield Strength = 501 Mpa

Steel, 4130 annealed:
Modulus of Elasticity / density = 26.11 Gpa cc/g
Yield Strength = 460 Mpa

Titanium, Grade 5 annealed:
Modulus of Elasticity / density = 25.73 Gpa cc/g
Yield Strength = 830 Mpa

As you can see the stiffness to weight ratio of all the metals are within 5% of each other. So using these metals you can't make a part stiffer and lighter. But what you can do is increase a parts yield safety factor with the proper material selection.

Choose your materials wisely!

Garth Frederick
2004 Project Engineer
PSU Racing

1996-2002 Georgia Tech Motorsports Alumni<HR></BLOCKQUOTE>

This is true but seeing as you aren't going to make a strong enough part using welded aluminium you have to machine it and you very rarely see machined aluminium uprights for these cars that are as stiff as the fabricated steel ones.

This isn't just about the material properties, it's also about the manufacturing abilities of the uni and students and the cost of those materials. Why make a machined 7075-T6 upright when a welded mild steel one will weigh about the same and cost a small fraction of the aluminium one?

Ben

University of Birmingham
www.ubracing.co.uk (http://www.ubracing.co.uk)

[Frank]

the material costs are not that much

even a beastie rear upright should only need a US$50 billet

and i guess it depends on what is easier / cheaper (which depends on a number of different resources)

post machining a hacked up mild steel stress skin thingy

or

NC'ing a billet of ally

http://www.uq.edu.au/fsae/2003%20Photos/Comp/Dsc01223.jpg