Just a query regarding some 6082 grade aluminium which is in a sheet 3mm thick. Will this bend to gentle radius easily enough?

Is 6082 a high strength alloy grade and will it be good for a floor on my race car. I've had problems with intrusion on 2mm 1050 which is what I have used previously. This has been punctured last weekend.

Please let me know if there is a better grade to use or if you think 3mm is overkill?

What punctured the 2mm ally floor?

Would it be better to add an extra layer of 2mm in the vulnerable areas - under ya bum

Its not just the puncturing, 1050 alloy in 2mm with the off road running we do just gets so dented so quickly and looks tatty!

I would have thought that 3mm 6082 is overkill. Its tensile strength is approximately 3 time 1050, so it would be like 9mm sheet!

I remember noting that one of the kit manufacturers uses 1.2mm 5000 series alloy, which is about 1.6 times the strength of 1050.
In terms or wear resistance, the relative hardness of 500 series alloys is about 1.8 times 1050, and 6082 about 2.8 times as good.

I was going to 2mm 5083 for my floor.

Regards
Hugh

Thats brilliant information High, thanks!

One last question though was on wether it will bend round a shallow radius OK?

I think I may opt for some 2mm sheet instead!

Should bend easy enough - may need some blocks and rachet straps to persuade it while you drill and rivet to the chasis.

I have bent 6082 50mm*6mm strip in a 50mm radius ok. Sharp bends tend to tear at the crease, and definately not good if bend back and forth a few times, but I don't know what the minimum recommended radius is.

What radius do you intend to bend to, what width of sheet and how do you intend to do it? Remember its much harder to bend than 1050.

Regards
Hugh

If you are going to research the quality of the aluminium you'll need to know the type of treatment is has been through. There should be a code, for example T6 following the 6082 which, depending on the treatment, will have a huge impact on hardness, malleability etc.

HTH

Mike

Yes it's T6, is that OK to bend?

I've used a hell of a lot of 6082 T6 but for machined components. The only experience I have of bending was in accidents but the cases I have seen the material stood up well to being bent and very rarely tore. These were components 6mm thick bent cold in violent accidents.

I'll have look and see if I can find you some more reliable data.

Cheers,

Mike

I've had a look at Aalco's spec for this material and while it gives a 'Good' for cold workability it shows an 11% elongation before breakage. Assuming the outer edge of your rad takes all the elongation this would mean that a cold bent rad of 28mm (internal) would be the tightest you could make while respecting the 11% elongation.






TBH I find this a bit hard to believe and my approach would be to take a test piece and simply try some folds, first cold and then hot.

The Aalco stuff is here

And there's a good bit of info here on an aluminium boat builders forum.

I suspect that nearly all the bends in the ally floors used on Locosts exceed the specified elongation. It's the inner material that is streched less that holds the job together!

Out of interest if you went to 2mm 6082 T6 the minimum internal rad drops to 19mm and 1.5mm to 14mm.

I hope this is of some help.


ETA Here's a good bit of help on annealing 6061 T6 which is a very close alloy to the 6082 T6

[Edited on 2/9/10 by MikeCapon]

When i looked at making my floor i ended up going for 1.2mm steel. It was much better at resisting penetration, was weldable in (when i started silkaflex wasn't common knowledge) and weighed the same as 2.something, maybe 3mm ali.

Sure i posted about it a few years ago.

Mike you are right, however 6082 sheet seems to be almost universally supplied as T6 grade 'off the shelf'. Its officially listed as 'not suitable' for cold bending by eltheringtons (The supplier I use). You can phone them on 01482 621610 for technical assistance.

From their site, if you can reconstruct the table:

Aluminium Guide




Home > Aluminium Stockholding > Aluminium Guide
Rolled Product Alloys
Specifications Mechanical Properties General Characteristics

"Alloy" "Tempers" "Old References" "0.2% Proof Stress (Mpa)" "min. Tensile Strength (Mpa)" "Elongation
% on 50mm *Depending
on thickness" "Typical Hardness HBS" "Cold Forming" "Machining"
1050 H14 S1B 85 105-145 2-6 34 V F
3103 H14 NS3 120 140-180 2-5 45 V F
5005 H24 - 110 145-185 3-8 47 G G
5251 H22 NS4 NP4 120 190-230 4-12 56 F F
5083 O NS8 NP8 125 275-350 11-16 75 V G
5754 H111 AlMg3 MIN 80 190-240 12-18 52 G V
6082 T6 HS30TF 260 310 6-10 94 N G


Materials are graded thus E-excellent V-Very good G-Good F-Fair P-Poor N-Not recommended. Tempers indicate hardness for example the 3rd digit (e.g. the 4 in H14) indicates the degree of hardness (e.g. for 1050 & 3103, 2 is the quarter hard, 4 is half hard, 6 is 3/4 hard and 8 fully hard). The 2nd digit (e.g. the 1 in H14) shows the method used to achieve hardness; 1 is rolled to hardness, 2 is rolled more than required then partially annealed ‘back’ to the correct hardness. M represents ‘As manufactured’ and O means soft (annealed).

1050 is the standard commercially available 99.5% pure aluminium sheet. Excellent resistance to corrosion, easily welded and fabricated. Common Uses: Insulation & flashings, vehicle panelling & signs, most general uses.
3103 is slightly harder than 1050 mainly due to the addition of manganese, other properties similar. Common Uses: Roofing sheet & vehicle panelling.
5005 is of an architectural anodising quality. Medium Strength. Common Uses: Decorative & architectural signs and curtain walling. However for a guaranteed consistent anodised finish, alloy J57S should be requested.
5251 is a medium strength alloy, work hardens rapidly, easily welded & resistant to salt water. Common Uses: Panelling, Internal cladding in ships, tanks & containers.
5083 is a high strength alloy, good weldability & corrosion resistance. Very resistant to sea water industrial atmospheres. Common Uses: Pressure vessels, road & rail transport and ship building.
5754 offers good weldability & corrosion resistance. Resistant to salt water. Common Uses: treadplate for flooring and general fabrications.
6082 is a fairly high strength Alloy but unsuitable for bending. Common Uses: Flat bed & Drop side lorry bodies and structural engineering.



Hope that helps
Regards
Hugh

ETA, had a read of the aalco data- interesting that they say 6082 is good to cold work! MikeCapon - thanks for the minimum bend data - I'll keep a nore of that.
Hugh

[Edited on 2/9/10 by hughpinder]