390 Aluminum

[JPMach]

Where can I find hypereutectic 390 raw material? preferably somewhere close to WI. I've tried a few places on the net and one of my local suppliers and just cannot seem to find it. I'm trying to put a quote together and need to find like some 4" round stock probably like ground on the outside or something as it is for pistons, can you even get it this way?

Also any cutting recomendations would be much appreciated (how does it compare to 6061).

JP

[psychomill]

Give these guys a call... http://www.metprodco.com/index.php

They produce the 390 alloy and can answer all of your questions about the material...

[NC Cams]

If you want billet piston alloys, use 4043 (high silicon content for lower thermal growth) or 2618 (better high temp strength albeit more thermal expansion). There are others that can be used but these are the predominant alloys that could/should be used/considered.

Both need to be solution and age heat treated prior to machining to achieve optimum hardness/toughness/durability (go for a BHN hardness of 120 to 140).

Both are MUCH more machineable in piston configurations than 390. Besides, they also do not need to be specially treated/plated/etched so as to make them compatible with use in conjunction with piston rings and/or piston pins as 390 needs to be.

390 is not really as suitable for pistons as it is for blocks and/or other near net shape cast items.

BTW: hypereutectic piston alloys are real bears to machine. When pistons are made of hypereutectic alloys, you pretty much have to use diamond tooling to cut the materials properly and accurately.

6061 has not been used in any commercial automotive/truck/racing piston use that I know of.

[JPMach]

Thanks for the info I will pass it to the customer if he ever shows up

JP