CPM3V Properties

Nullack, normalizing is taking a material above it's transformation temp and letting it air cool. Non-air hardening materials result in a usable structure that is not hardened. Air hardening grades harden. It may be simpler to say you can't technically normalize an air hardening grade due to the wrong structure issue. I agree with Larrin that decarb and carburizing are not an issue, that is unless they show up during heat treatment. 3V will behave like any other tool steel and you need to address these issues if they show up.
Compressive strength was mentioned. Compressive strength is directly proportional to hardness (that's what a Rockwell test measures) and is about 5-10% higher than tensile. Metallurical data on high end steels like stainless and tool steels is very limited. You will always have some subjective input because of that. It's general, but the basics of all steels are usually pretty close if compared to the right group of alloys. The key is to not over analyze the small stuff. Steels somewhat simple and the properties, even though variable, are somewhat predictable.
 
Thanks Ed. Is there no further gain to mechanical properties by trying to further refine the grain of cpm3v through heat treating or cold working it? (that's the reason I had for thinking about normalising cpm3v. I've read elsewhere for other materials that normalising for grain refinement might harden the part which I don't care about as Im quenching anyway thereafter. I've also read normalising could crack other materials but so far I have not personally seen this.)

Also how does it polish up on the surface finish?
 
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The grain size due to the PM process is nearly impossible to improve upon by thermal cycling. More than not it will grow the grain size. Conventional grades have relatively big grain size and can benefit from thermal cycling if done right. Done right is difficult even with controlled furnaces etc. At home, more than likely not beneficial. Grades with vanadium carbide in their structure can be a pain to polish. This is mainly due to the fact vanadium carbide is harder than most abrasives used for polishing. Ask someone to mirror polish 10V or S90V and they will probably have a heart attack. The carbides in PM steels are 4-6 microns in size so polishing to that level is no problem. Beyond that, use diamond polishing if you can, or leave it alone. I've got one of Phil Wilson's chef knives in 3V with a hand rubbed finish and it looks great and works great.
 
Thanks Ed that's great. If you ever come my way to Australia Ill shout ya a night on the town. I greatly appreciate you sharing your insights.
 
So Ed, Having launched this product with Crucible, would you by chance hail from the the "burgh" near the rivers 3?

When polished, how would the corrosion resistance be, assuming the blade is not abused, for household/kitchen use on acidic fruits for example.
 
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