Category: Steels

4 thoughts on “Steels”

  1. Thanks for what you are doing. There is so much misinformation, hyperbole, and exaggeration being presented as fact on the internet regarding knife blade steel. I felt like the skies cleared when I discovered your site. I really appreciate your science-based approach to demystify so many issues.

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Edge Retention, History - Articles - Books, Super Steels

CPM-15V and the Lost CPM-20V – How Much Vanadium Can you Add?

Larrin

Thanks to Tim Marais, Daniel DeRosia, Jess Hoffman, David Rogers, Mo, John Macklis, and R. Thomas Buffenbarger for becoming Knife Steel Nerds Patreon supporters!

History of CPM-15V

CPM-15V is essentially a higher vanadium extension of CPM-10V developed by Crucible steel in the late 1970s. I wrote about the history of CPM-10V in this article so I won’t copy-paste all of that here. Prior to powder metallurgy technology it was known that adding higher vanadium would lead to greater wear resistance due to the very high hardness of vanadium carbide. However, once the vanadium content exceeded 4-5% the carbides would be large enough that the steel would fail in forging, and toughness would also be reduced. So the highest wear resistance steel for many years was T15 high speed steel with ~5% vanadium. With CPM-10V they saw what the limit was for vanadium additions and found that once they reached about 11% vanadium the carbide size would be increased because the vanadium carbides would form in the liquid steel before the steel could be gas atomized into powder. Read about the powder metallurgy process in this article. The more vanadium that is added the higher the temperature where the vanadium carbides form. When the formation temperature is higher than the temperature of the liquid steel then they form prior to atomization giving the large carbides in the 11% vanadium PM steel below (labeled CPM 11V): read more

Edge Retention, Super Steels

Edge Retention Testing of Seven More Steels – XHP, SPY27, Maxamet, Rex 45, 420, T15, Rex 76

Larrin

Thanks to Knife Thoughts, Nicholas Rossi, Jason D. Stone, and Ken McCurdy for becoming Knife Steel Nerds Patreon supporters!

Update 1/5/2024: I neglected to mention in the original writeup of this article that the Z-Max was retested along with the new Maxamet and Rex 121 tests. The total cardstock cut was updated from 909 in the original testing to 948 mm. read more

Edge Retention, History - Articles - Books, Super Steels, Toughness

Vanadis 8 – Better than CPM-10V

Larrin

Thanks to Will and Justin Mann for becoming Knife Steel Nerds Patreon supporters!

My book Knife Engineering is available for Christmas and Hanukkah presents.

History of Vanadis 8

The history of Vanadis 8 goes back a lot further than just the steel itself, really we have to know the history of 10V to know all of the background that is relevant. You can read about CPM-10V in this article. CPM-10V is important because Vanadis 8 is intended as a replacement for CPM-10V, or at least for similar applications. CPM-10V was developed by Crucible in the late 70s, as the first powder metallurgy steel to utilize a microstructure made up of only vanadium carbide, as opposed to chromium and molybdenum/tungsten carbides. This gave 10V a combination of good toughness along with very high wear resistance from the ~10% vanadium and therefore ~17% vanadium carbide. read more

Corrosion Resistance, Edge Retention, Steel and Knife Properties, Super Steels, Toughness

CPM-S110V Steel – History and Properties

Larrin

Thanks to Aaron @ Gough Custom, Aaron McVay, Mark Scott, Jeffrey St. Claire, Grant Seim III, and saiiiiiii1 for becoming Knife Steel Nerds Patreon supporters!

I’m eventually going to stop plugging my book Knife Engineering in every new article, but that day is not today. Go buy one for yourself, and everyone you know, as a Christmas present. read more

Carbides, Corrosion Resistance, Niobium-Alloyed, Nitrogen-alloyed, Powder Metallurgy, Steel and Knife Properties, Super Steels

What is the Future of Stainless Knife Steel Design?

Larrin

Thanks to Aram Compeau, Gordon Olafson, and John Walton for becoming Knife Steel Nerds Patreon supporters! I have an update on Patreon about the “rare earth” elements in AR-RPM9 steel.

I completed a minor revision to my new book Knife Engineering to correct a few typos. Some readers outside the USA also asked for more conversions from Fahrenheit than were present originally, so I incorporated both Celsius and Fahrenheit everywhere in the book in the text and tables, though some images and charts still have only one temperature scale or the other.  I wouldn’t say that the changes in the revision are big enough to buy a new one if you have it already, this is not a new edition, but if you haven’t purchased one yet this is as good a time as any. read more