Super high carbon/high vanadium steels.

[bodog]

At first glance, that might appear to be the case. However, even in 1095, dissolving all the carbides is not desirable. First, it puts too much carbon into the austenite and, upon quenching, the hardness will start going down. This decrease in hardness is due to an increase in retained austenite. Second, those undissolved carbides provide the wear resistance these complex alloys are known for. Third, dissolving those carbides and putting carbon into the austenite also means putting the other elements into the austenite, such as chromium, vanadium, etc. These will typically increase the amount of retained austenite as well. Third, these complex alloys require high temperatures to harden. The carbides act as speed bumps to slow down grain growth. If they were all gone, the grains would grow very large very quickly. Now, some carbides have to dissolve. The trick is how much and at what temperature. It's a balancing act; just enough, but not too much.

So say you had a bar of steel with 30% carbide volume in the annealed state and were able to dissolve all of the carbides, just as an experiment, not because you think it'd be beneficial. If you were successful in dissolving all of the carbides but your final hardness was only capable of being 58 HRC with, say 10% retained austenite, would the final product act like any poorly treat eutectic steel at 58 HRC that also had 10% RA? Am I looking at this right or are there other factors that need to be taken into account like pearlite and bainite (not that I'm very familiar with what these are exactly).

Is there any way of checking any of this once you get a final product? If I bought a knife from whoever and the steel was performing badly, how could I pinpoint was caused the problem without breaking the blade to see the grain size? I'm assuming there would need to be some pretty expensive testing done, but is it possible?

Do most of these major manufacturers simply follow the industry standard hardening protocols? Is there any real reason not to?

 

[me2]

So say you had a bar of steel with 30% carbide volume in the annealed state and were able to dissolve all of the carbides, just as an experiment, not because you think it'd be beneficial. If you were successful in dissolving all of the carbides but your final hardness was only capable of being 58 HRC with, say 10% retained austenite, would the final product act like any poorly treat eutectic steel at 58 HRC that also had 10% RA? Am I looking at this right or are there other factors that need to be taken into account like pearlite and bainite (not that I'm very familiar with what these are exactly).

Is there any way of checking any of this once you get a final product? If I bought a knife from whoever and the steel was performing badly, how could I pinpoint was caused the problem without breaking the blade to see the grain size? I'm assuming there would need to be some pretty expensive testing done, but is it possible?

Do most of these major manufacturers simply follow the industry standard hardening protocols? Is there any real reason not to?

Your first question is fairly complex and starts from a lot of assumptions. A simple answer is no, it wouldn't act like any poorly treated eutectoid (eutectic is liquid to solid, eutectoid is from solid to solid). There's no telling what you'd wind up with.

If you bought a poorly performing blade, and you eliminated sharpening and geometry issues, just breaking the blade to see the grain size won't tell you much. It may not even tell you the grain size. Some testing would be needed. There's no way to tell what manufacturers use. It may be stock HT procedures, or they may have developed their own.

 

[bodog]

Your first question is fairly complex and starts from a lot of assumptions. A simple answer is no, it wouldn't act like any poorly treated eutectoid (eutectic is liquid to solid, eutectoid is from solid to solid). There's no telling what you'd wind up with.

If you bought a poorly performing blade, and you eliminated sharpening and geometry issues, just breaking the blade to see the grain size won't tell you much. It may not even tell you the grain size. Some testing would be needed. There's no way to tell what manufacturers use. It may be stock HT procedures, or they may have developed their own.

You're full of all kinds of helpful information. Thank you again!

 

[stezann]

at 4%-4.3% carbon in solution you have liquidus
Anyway your first question... yes, a fine ausgrain won't help so much if you don't have comparable size carbides.
So called supersteels sell a lot, so don't expect makers using them to tell you they are not super. All those box shaped carbides do wonders if you need to protect surfaces from wearing (mold and die industry, they developed those steels), but for keen edge tools we need finer carbides, so we rely on simpler steels or powder tech. steels.