Repair Weld (build-up) on 410 Stainless

By jandruschi Date 01-25-2006 19:59

I am evaluating a proposed in-service repair: a very small build-up on a 410 stainless steel piston heat treated to 180-120ksi. The part has tolerances that preclude the conventional PWHT of tempering at 1200F or re-hardening. The fabriicator has proposed GTAW of the deposit (a ring around the piston) using 410 wire, with minimal preheat, then PWHT of about 400F for stress relief.

The HAZ and weld on a sample were not unusually hard (</= base metal). HAZ was about 0.080" deep.

Review of various popular handbooks (ASM, etc.) reveal a consensus,: the weld and HAZ should be rehardened or tempered at 1200-1300F as PWHT. Anything else might work on small parts but is unconventional and requires some sort of qualification. Primary issue would be brittleness.

My question: does anyone have experience making small welds of 410 on 410 with minimal PWHT and therefore some idea of how deleterious such a process actually is to ductility (and hopefully fatigue)?

By G.S.Crisi (****)

Date 01-26-2006 19:03

Would it be possible to make Vibrational Stress Relieve (VSR) in this piece instead of PWHT? Have you considered that? I'm just asking, not recommending, because I don't know the size nor other features of the piece.
The great advantage of VSR is that it doesn't cause the piece to warp or distort, as heat treatment does.
Giovanni S. Crisi
Sao Pauloi - Brazil