Spyderco Forums

https://www.diamondbladeknives.com/friction-forging

This is from the Knives of Alaska parent website. Has anyone heard of friction forging? Does it really accomplish all that they claim?

@Larrin, what do you think?

Larrin wrote about that here: https://knifesteelnerds.com/2020/02/

It's his second, of two articles from February of last year.

Yes I wrote about it, thanks Pokey. The technology is somewhat interesting though performance claims can be exaggerated, of course.

Interesting discussions and comments.

sal

Ok, I read all of that. Why choose D2 over something like S30V or S90V? How would SPY27 perform with friction forging?

Wayne Goddard, one of my mentors, told me about the program. I purchased one and tested it, and still have it.

sal

Doc Dan wrote: ↑

Tue Feb 16, 2021 11:26 pm

Ok, I read all of that. Why choose D2 over something like S30V or S90V? How would SPY27 perform with friction forging?

I don't know that friction forging would offer any advantages that the PM process doesn't already give you.

I've heard of "friction welding", maybe it's my pessimistic side but "friction forging" sounds like a sales gimmick.

The Meat man wrote: ↑

Wed Feb 17, 2021 3:48 pm

I don't know that friction forging would offer any advantages that the PM process doesn't already give you.

I can get pretty much any knife I own sharp enough to hurt myself, if I slip. If I'm going to be cutting a material that's known to dull knives I'll use one made of Maximet. So far, for what I use them for, I haven't needed one where it needs to be "springy".

I'll admit, maybe, I'm doing it wrong, but I'll just stick with the ones I've got. :o

Evil D wrote: ↑

Wed Feb 17, 2021 4:15 pm

I've heard of "friction welding", maybe it's my pessimistic side but "friction forging" sounds like a sales gimmick.

It's virtually the same process, spin a carbide tool at high speed while forcing it into the substrate. Great friction is created turning the metal into a hot pliable state, think alloy taffy. The hardest part to wrap your head around is that it doesn't melt. It's right on the edge of melting but instead of creating a re-solidification cast structure you get a homogenous fine grain.

Friction stir can be used to join metals that are not weldable by conventional arc welding processes, like joining high carbon steel to 7075 aluminum

sal wrote: ↑

Wed Feb 17, 2021 2:07 am

Wayne Goddard, one of my mentors, told me about the program. I purchased one and tested it, and still have it.

sal

What did you find out? I'd really like to know.

Pokey wrote: ↑

Tue Feb 16, 2021 8:34 am

Larrin wrote about that here: https://knifesteelnerds.com/2020/02/

It's his second, of two articles from February of last year.

This was a good article, as usual. But, it does not answer some of my other questions, such as why D2 and not S90V, etc.? How much hardness can be gained and what is the optimum temperature? At what point is the grain the finest and is there such a thing as being too fine?

Interesting. Definitely another take on the differentially hardened approach but I wonder how much more cutting performance it actually liberates in small knives.

I suspect D2 is being used as it's a simple air hardening tool steel and very well characterised.