The Future of Stainless Knife Steel Design

[Larrin]

A new article about why non-stainless powder metallurgy steels are better than the stainless versions and what can be done about it. I also summarize some of the discoveries in steel design over the past 20-30 years and which of those might be applied to future stainless knife steels to make them perform closer to the non-stainless steels. https://knifesteelnerds.com/2020/10/12/ ... el-design/

[rabbitanarchy14]

great arcticle, as always and thank you for you work and contribution. but what it honestly tells me is i know very very little about metals. much to learn from you.

[JohnDoe99]

The major loss in corrosion resistance is a problem from a business standpoint. Actually not just business, but if the edge corrodes, then that of course compromises the steel and accordingly decreases edge retention, requiring a new sharpening, which defeats the purpose of the larger carbide load. Harder carbide aggravates sharpening because of the double edged sword of wear resistance, and the better edge retention really shines on specific medium.

It's the old Crucible argument from the birth of s30v, which keep in mind they have to sell.

[Larrin]

The major loss in corrosion resistance is a problem from a business standpoint. Actually not just business, but if the edge corrodes, then that of course compromises the steel and accordingly decreases edge retention, requiring a new sharpening, which defeats the purpose of the larger carbide load. Harder carbide aggravates sharpening because of the double edged sword of wear resistance, and the better edge retention really shines on specific medium.

It's the old Crucible argument from the birth of s30v, which keep in mind they have to sell.

The first version of S30V had only 2% vanadium but Chris Reeve wanted more edge retention. Crucible also came out with S35VN and CPM-154 which were tougher and easier to sharpen but S30V continues to outsell both. It’s the knife companies that decided on S30V not Crucible. Or perhaps their customers.

Using vanadium doesn’t automatically make something hard to sharpen. Very few complaints about sharpening 3V, CruWear, or 4V. Sometimes complaints about CPM-M4, S30V, or M390, and many more complaints about 10V, S90V, or S110V. I think the overall wear resistance may matter more. For example, 3V is only about 5% carbide and 95% steel. 4V and Vanadis 4 Extra brings that up to 8%. Though of course I have pointed out the abrasive hardness issue many times. CBN/diamond make sharpening faster with vanadium steels though that is also true of non-vanadium steels. I personally don’t like the trade off of slightly easier sharpening to bring the toughness down by half. But the popularity of M390 is a good counter-argument about what “the public” prefers. I still think education could push the needle, especially if something truly better came along.

[zuludelta]

Another excellent read, Larrin.

I do have a question, though—and maybe it was addressed in the article & I just missed it—but what are the possible implications regarding cost with these proposed improvements to future PM stainless steels? I understand that economies of scale will probably ameliorate cost if and when these improvements become more widespread, but I imagine the financial outlay for certain elemental substitutions & additions are not scalable, and may in fact probably rise as the demands of production increase.

As a knife hobbyist with a limited budget (as I imagine many of us are), I'm always asking myself if any improvements in a cutlery steel are worth the additional cost, and that's probably one of the main reasons why I have only a theoretical interest in many of the "latest & greatest" steels.

[Larrin]

Another excellent read, Larrin.

I do have a question, though—and maybe it was addressed in the article & I just missed it—but what are the possible implications regarding cost with these proposed improvements to future PM stainless steels? I understand that economies of scale will probably ameliorate cost if and when these improvements become more widespread, but I imagine the financial outlay for certain elemental substitutions & additions are not scalable, and may in fact probably rise as the demands of production increase.

As a knife hobbyist with a limited budget (as I imagine many of us are), I'm always asking myself if any improvements in a cutlery steel are worth the additional cost, and that's probably one of the main reasons why I have only a theoretical interest in many of the "latest & greatest" steels.

Nitriding powder and adding graphite to powder are both extra steps that mean labor and logistics costs. Neither of those processes are necessarily required for new steels, however. In terms of alloy additions nothing I talked about is really any more expensive, certainly not more so than anything else already available. Expensive alloying elements include molybdenum, niobium, vanadium, tungsten, and cobalt, and we already have many steels that use those liberally.

[sal]

Hey Larrin,

Excellent as usual.

I heard a rumor about a Larrin steel? Any thoughts to share? I want to put in for first dibs, if nobody else has?.

sal

[Larrin]

Hey Larrin,

Excellent as usual.

I heard a rumor about a Larrin steel? Any thoughts to share? I want to put in for first dibs, if nobody else has?.

sal

Nothing yet!

[sal]

Can we help?

sal

[Larrin]

Can we help?

sal

I will let you know. :)

[dj moonbat]

Oh, man. If our own resident PhD and Sal set their minds to making the perfect production knife steel, I’m going to need to cut back on luxuries like shoes for my kids and that second dress my wife’s been wanting.

[p_atrick]

This was an absolutely fascinating article. Thanks for sharing.

[JuPaul]

Oh, man. If our own resident PhD and Sal set their minds to making the perfect production knife steel, I’m going to need to cut back on luxuries like shoes for my kids and that second dress my wife’s been wanting.

Lol - exactly! One steel to rule them all...

[Dazen]

Awesome article Larrin! I really makes me wonder what’s next, and how soon will Spyderco make a knife with it!

[Enactive]

Larrin, once again, an outstanding article. I think this one is particularly excellent. Thanks so much for your contributions! :cool:

[Bemo]

Really awesome stuff. This is the best forum hands down. I understand so much more about the trade offs between wear resistance, hardness, sharpness, toughness and stain resistance. And it really is helpful. Living in an arid part of the country, corrosion resistance isn't the highest priority but I like tough steels. I'd rather deal with a re-sharpening than taking chips out. Thanks so much Larrin!

[Holland]

Awesome read as usual, thanks for sharing!

[curlyhairedboy]

Great overview of steel development from the perspective of edged tooling. I think you're really doing well refining the themes that come through in each post.

For the NioMax heat, did you work with a particular manufacturer? Part of me wonders if recent trending interest in proprietary/exclusive steel chemistries is going to be supported by small batch sizes from foundries. We could see some rapid iteration if the aim isn't production-level output.

[Larrin]

Great overview of steel development from the perspective of edged tooling. I think you're really doing well refining the themes that come through in each post.

For the NioMax heat, did you work with a particular manufacturer? Part of me wonders if recent trending interest in proprietary/exclusive steel chemistries is going to be supported by small batch sizes from foundries. We could see some rapid iteration if the aim isn't production-level output.

I am working with Alpha Knife Supply on NioMax.

Lab scale production is good for development but not for cost in terms of dollars per pound. But smaller batch production is something I have considered in the past. Either way it doesn’t seem feasible for powder metallurgy steels as the lab scale companies are few and the costs astronomical.

[curlyhairedboy]

very true. now you have me wondering if we can persuade some very-well-off knife fan to try making a single crystal blade....