Your ideal rockwell hardness?

[tomhosang]

1. Heat treat (none of the below matter without a solid HT)
2. Hardness (proper hardness comes from a good HT)
3. Geometry (can't take things to thinner geometry without adequate hardness to support it)
4. Steel type/composition (least important. "Lesser" steels that have the above 3 will perform better than "better" steels that don't)

With all that being said, I love my tool steels that are 65+.

 

[scdub]

With modern tech, the hardness/toughness debate is kinda moot. We have highly alloyed 60+ HRC-possible steels that have higher toughness than low alloyed 55-57 HRC steels. Some of the steel/geometry used in those BladeSports chopper knives could be easily adapted to kitchen duty.

Do we though? I mean there might be a case or two, but generally a low alloy steel will be tougher than a high alloy steel at the same hardness.
I love having a range of hardness levels. I have Japanese kitchen/utility knives in white paper steel or Aogami super blue at ~65, while my outdoor blades go from ~56 for tomahawks to ~56-60 for fixed blades.
I believe my hardest knife is a flexible ceramic kitchen utility from Rahven knives which I sharpened once on arrival and haven’t touched since. They don’t publish the measured HRC but it’s probably getting up to 68+…

 

[Londinium Armoury]

I personally think low alloy high HRC steels are best suited for cutting blades. You do lose some of the high wear properties of high alloy steel. But you still retain the high edge stability. And as long as you aren't using your knives as actual crow bars. A 65 HRC knife should be fine in low alloy steel. It's not going to act like a true spring and will have a limit before it snaps. But I don't think those things need to be a concern in a cutting blade. Nothing wrong with highly alloyed stuff it has its place.
I would say high alloy steels are good work general use knives that need a working edge, like maybe cardboard shredders, zip tie cutters, warehouse duties etc. But for slicing blades and fine cutting tools like kitchen knives, even folders I would choose low alloy high HRC everytime. Those carbides are not great for fine edges.

 

[K.O.D.]

I could say about 100 things right now that would land me in the "Dumbass Valley of Death"!

I'm evil like that.

 

[JR42]

Yeah, good thing Cedric and Ada exposed that. Lots of non-knife folk probably fell for that.

I’ll admit I’m not that familiar with the exact mechanics behind HRC. I know the Kershaw Camp series has HRC 56 I think? And the Beckers are around 58-60 (correct if I’m wrong). I’ve also heard that steels like ZDP-189 can comfortably reach into the range of 60s.

The Camillus Beckers were around 59, and the KaBar Beckers are around 57.

 

[Fir Na Tine]

A smart man once said, “A dull knife cuts better than a broken knife.” I say it is also easier to resharpen a dull knife than a broken knife. I prioritize toughness over the last few percentage points of edge retention. I also hate chips in my blade. A big difference in a touch up and a repair.

 

[Spears]

Yeah, good thing Cedric and Ada exposed that. Lots of non-knife folk probably fell for that.

I’ll admit I’m not that familiar with the exact mechanics behind HRC. I know the Kershaw Camp series has HRC 56 I think? And the Beckers are around 58-60 (correct if I’m wrong). I’ve also heard that steels like ZDP-189 can comfortably reach into the range of 60s.

I've seen some ZDP-189 get up to 67. Look like toughness at 67 of ZDP is around 8 ft/lb for toughness, which, honestly is kinda impressive considering that's the same toughness for 1095 at 60.

Do we though? I mean there might be a case or two, but generally a low alloy steel will be tougher than a high alloy steel at the same hardness.
I love having a range of hardness levels. I have Japanese kitchen/utility knives in white paper steel or Aogami super blue at ~65, while my outdoor blades go from ~56 for tomahawks to ~56-60 for fixed blades.
I believe my hardest knife is a flexible ceramic kitchen utility from Rahven knives which I sharpened once on arrival and haven’t touched since. They don’t publish the measured HRC but it’s probably getting up to 68+…

Generally? Yea, I guess; however, the low-alloy steel also means less hardenability, so, yea, it'll be tougher because it's also softer. Though, really, if you go look at high-alloy non-stainless steels and compare the toughness with commonly used low-alloy non-stainless steels for knives, the toughness is pretty similar at any given hardness. The high-alloy stuff can just maintain same toughness of a low-alloyed steel, but at a couple points higher hardness. So, why wouldn't you want to use (besides the obvious cost in manufacturing) the higher-alloy stuff that has the same toughness at higher hardness (meaning higher strength so you can go a little thinner at edge) and the additional benefit of having some carbide content to increase wear resistance?

With things like tomahawks and axes, any issues with toughness can kinda be brute forced out with thicker geometry. I mean, there used to be hawks/axes made out of stone; stone isn't the toughest of materials but a thick enough cross section and you can still do work.

I think the high impact ceramic stuff was over 70 and technically beyond the HRC scale.