Aluminum Casting in Oven

[BobM2]

We're thinking about power coating our aluminum products. The powder needs to be baked @375 Deg F for 10 minutes. The castings are 356 - T6 both permanent mold and sand cast. I'm worried they might distort in the oven. Anyone with experience with something like this?

 

[unclesyd]

I have seen numerous parts made from 356-T6 powder coated and have never seen nor heard of any problems.
As you know 356-T6 is used in come pretty warm places and is ceramic coated. We used a phenolic coating that required a bake at 250°F and quick excursion to 600°F on this alloy.

I don't have this particular alloy on my list of reheat times but the lowest maximum allowed time at 325°F for any alloy listed is 1 hour.

 

[NickE]

They wont distort. I'd be more worried about overaging, though I dont have enough practical experience with Al (esp 356-T6) to figure that one out.

nick

 

[TVP]

The artificial aging temperature is usually ~ 160 C for this alloy, so it will definitely overage if the powder curing temperature is 375 F (~190 C). You should investigate a lower curing powder if the mechanical properties need to be at T6 levels.

 

[swall]

Get some 356-T6 p.m. test bars from your casting supplier and run them through the paint cure oven at normal line speed.Then run a tensile test (your supplier or outside test lab) to see where your mechanical properties are.

 

[BobM2]

All great input! Thanks.