Where do knife steels come from?

[Mark Reich]

Thank you very much Scott. We're learning although slowly. So I think that we read earlier in this thread that the potential HRC on this powder material (SV30) is in the 60-62 range. Does that mean approximately the same for sintered? Here's where we're going next with this question assuming that the answer is in the affirmative. John Lucas mentioned ( in one of his wood working posts here or emails) that he had done some work with sintered hand plane blades. He commented that they had arrived quite sharp, were very durable edges, but were extremely difficult to re-sharpen. Does this seem to follow? If so, why would they be so difficult to sharpen?

Yes, thank you for the clarifications you point out, Mr. Scott. I am so used to the new version of blade steel type M4, powder CPM M4, I tend to overlook the other ones. Besides Hitachi's awesome "colored" high carbon blade steels, they make my favorite stainless powder steel, ZDP 189.

Your suggestion of CPM steel orifices for injection molds does sound most likely as well.

I assume that one could use the term "sintered" to describe the formation of an ingot of powder steel, or the formation of a molded part. It seems like totally different ways of ending up with about the same resultant steel to me. With molded, sintered parts, you can eliminate what would be a lot of arduous, if not impossible, machining.

Whether you're talking about molded powder steel parts or rolled powder steel blade material, the hardness and other properties are going to totally depend on the heat treatment of either one. 

I too would assume that John Lucas's plane blades are rolled, and not "just sintered", as Mr. Me2 described. In other words, as far as sintered steel blades go, they are not molded, but rolled and ground, like all powder blades, because it's very straightforward stock removal. 

I have a Veritas PM 11V plane blade and a PM 11V wood chisel. I know of other woodworking blades in CPM 3V, and it wouldn't surprise me if they are identical, with Veritas just giving theirs a proprietary name. I don't know of any other steel designated PM 11V, and I rather doubt Veritas would be able to convince Crucible or whoever to make a different powder steel just for them. 3V would be a good candidate for woodworking blades, as it is a very tough powder steel. 

Manufacturers almost certainly use diamond or CBN abrasives to turn out acceptably sharp powder steel blades from the factory. John Lucas may be using his standard regimen for good carbon steel blades, which simply won't be effective on high vanadium powder steel.