H1 Steel - How it Works

[Larrin]

An article about the highly corrosion resistant H1 steel. It's very different than most other knife steels for several reasons, including that the steel is not heat treated by the knife manufacturer. In fact, the steel isn't quenched and tempered like typical knife steel. Learn about how it works instead here: https://knifesteelnerds.com/2019/06/24/h1-steel-how-it-works/

 

[Nick Dunham]

Interesting, thanks! I wasn't aware of the used of work-hardening in modern production knives at all.

My previous work involved a lot of austenitic stainless (304/304L). It's interesting to note that we saw work hardening during machining when feedrates didn't match speeds (eg, not being aggressive enough on a drill press or bandsaw). Of course grinding differs from conventional machining in some ways, but both rely on shearing the material.

My suspicion is that localized stresses are very high, which perhaps leads to additional work-hardening.

 

[Larrin]

Interesting, thanks! I wasn't aware of the used of work-hardening in modern production knives at all.

My previous work involved a lot of austenitic stainless (304/304L). It's interesting to note that we saw work hardening during machining when feedrates didn't match speeds (eg, not being aggressive enough on a drill press or bandsaw). Of course grinding differs from conventional machining in some ways, but both rely on shearing the material.

My suspicion is that localized stresses are very high, which perhaps leads to additional work-hardening.

Those are usually cases where the machining isn't working (rubbing not removing material). Of course if someone has some information on the degree of work hardening from grinding operations I would be happy to see it.

Edit: And that work hardening would only be at the surface. Sharpening would remove it.

 

[Willie71]

I have some generic low cost folding knives that I put in the glove box of all my vehicles, tool boxes etc. They are nicknamed Jarbenza knives. https://www.amazon.com/SE-KVS2101-3...coding=UTF8&psc=1&refRID=TNFZYZYRKBJQMXVW1HQ3

I tested them at Rc55, and most have serrated edges. I’m assuming the are H1 now that I read this article.

Now, I’m looking for an explanation of what causes non-magnetism in austenite?

 

[Larrin]

I have some generic low cost folding knives that I put in the glove box of all my vehicles, tool boxes etc. They are nicknamed Jarbenza knives. https://www.amazon.com/SE-KVS2101-3...coding=UTF8&psc=1&refRID=TNFZYZYRKBJQMXVW1HQ3

I tested them at Rc55, and most have serrated edges. I’m assuming the are H1 now that I read this article.

More likely some kind of 420/440.

Now, I’m looking for an explanation of what causes non-magnetism in austenite?

Electrical/magnetic properties of materials is not my strong suit. It has to do with electron states.

 

[Willie71]

More likely some kind of 420/440.

Electrical/magnetic properties of materials is not my strong suit. It has to do with electron states.

I looked it up, about a year ago, and it was like you said, to do with electrons, but it was just something I read, rather than actually understanding it.

 

[Larrin]

it was just something I read, rather than actually understanding it.

Then you and I are in the same boat.

 

[Nick Dunham]

Those are usually cases where the machining isn't working (rubbing not removing material). Of course if someone has some information on the degree of work hardening from grinding operations I would be happy to see it.

Edit: And that work hardening would only be at the surface. Sharpening would remove it.

Yeah, agreed. It also seems unlikely that Spyderco would allow their grinding to cause significant work hardening, considering that would likely indicate glazing or other counter-productive phenomena.