The authoritative public forum
  for Metal Finishing since 1989
  

  -----

Vacuum treatment for SS316L

I would like to make MIM parts using SS316L; this metal is being sintered in vacuum. Does the properties of the final part are identical to SS316LVM?

Oded Nissan
OPTONOL - NEVE ILAN, Israel
2001

---

Hello Oded!

It's my GUESS that the "VM" at the end of the "SS316LVM" designation refers to vacuum melting. If so, then they are not quite equivalent. Vacuum melting is inherently a nice clean process for making material, and you don't get that with MIM. In fact, the metal injection molding process is inherently a DIRTY one, since you have to mix the metal powder with a wax-like slurry to get it to flow into your mold. The debinder-ing step, done in a vacuum, and the vacuum sintering, are good things to do to make sure you don't make the situation any worse: but they don't clean the metal.

What I would do is check with my customer and find out if the reduced cost of the MIM process gets them sufficiently interested to reduce the requirement to 316L stainless. You may also have to prove that the part actually meets the carbon requirement after sintering, since MIM often adds carbon to the metal, from the debindering process.

Good luck!

Lee Gearhart
metallurgist - E. Aurora, New York
2001

---

Dear Lee:

If one starts with 316L MIM material and goes through the MIM process, will you end up with parts that meet 316L specifications? Stan Yang
- Laugna Hills, California, USA
2002