HY130 Seawolf submarine welds (hydrogen cracking)

Used as an illustration of hardness above Rockwell C40 producing hydrogen cracking — the weld wire was within spec but all alloying elements were at the high end of the range, producing effectively HY130 weld metal.

Hardness Vickers is about Rockwell C40, and 350 is about Rockwell C35. I told you in general you have a hard time getting cracking below Rockwell C30. Once you start getting into this 35 to 40 range, that's the problem with the HY130 Seawolf welds. I call them HY130 — the weld metal was sort of an HY130 weld metal. They were up there above Rockwell C40, and that's why they're getting hydrogen cracking. It was within the specification range for the welding wire, but it was on the high side. All the carbon was at the high end of the range, the chromium was the high end, the nickel was the high end, the vanadium, everything was the high end. So it really was an HY130 weld metal, it had crossed the line, and you could get very high hardness.