Deadboxhero wrote: ↑Sat Sep 06, 2025 8:52 am
LazyOutdoorsman wrote: ↑Fri Sep 05, 2025 7:56 pm
Also, what makes a steel retain that super sharp edge as opposed to "breaking down" into a working edge?
Differences in retained austenite, carbide size/volume, hardness, stress/fatigue, grain growth, plate martensite vs lath and heat build up during processing.
Lastly, your sharpening skill is probably the biggest most immediately controllable factor.
This means even the same steel can have a different behavior depending on the factors above.
7 years ago I had a similar question, at the time it seemed like CPM 4V was the answer since it seemed like back then it was the nexus of strength and toughness.
I ran it 65rc and ground the knife as thin as possible and the edge failed hard carving wood.
Maybe it was the 8% carbide volume?
I talked to Larrin at the time and he recommended a "matrix" steel.
Caldie, which is technically a matrix of "4V" without the carbide.
However, to dissolve all the carbide causes EXTREME grain growth without carbides to pin grains along with detriments from the other variables I shared above due to overaustenitizing.
This causes the properties to drop in performance.
So, it might not be as simple as hardness, impact toughness and carbide.
7 years later and I certainly know that the factors I shared above
(retained austenite, hardness, stress/fatigue, grain growth, plate martensite vs lath and heat build up during processing, how it's sharpened)
Play a bigger role than just the carbides alone.
To actually answer your the question it requires physical experiments that factor in the variables I shared above along with good control.
Simulation and speculation alone will not work.
You'll have to invest into some equipment and gather more knowledge and skills to execute the testing and correct your procedures after scrutiny.
Regardless, you will never achieve a fine edge that holds that kind of sharpness similar to how the working edge lasts but there are certainly features that could prolong it compared to other conditions.
TL:DR
Steel chemistry is not the only factor but the name of the steel gets the credit or the blame for expectations good or bad.
Now that we got that out of the way the answer is Nitrobe 77.
