Category: Steels
4 thoughts on “Steels”
Leave a Reply
Spyderco-Exclusive CPM SPY27 Steel Analysis
Thanks to ShavedAlpaca, giorgi chubinidze, and Сергей Якунин for becoming Knife Steel Nerds Patreon supporters!
Update 3/10/2020: We did a range of experiments with SPY27 to supplement the estimates in this article. You can read those experiments here.
ZDP-189 and Cowry-X – Super Steel or Overrated?
Thanks to Aaron T Grote, J. Braun, Mr. KnifeGuy, jethro fluegel, Philip Ward, and Matt Peterson for becoming Knife Steel Nerds Patreon supporters!
ZDP-189 and Cowry-X
ZDP-189 is a steel produced by Hitachi and Cowry-X is produced by Daido. I have not been able to find much background information on the development of these steels. Sal Glesser of Spyderco reported he first heard about ZDP-189 around the year 2000 [1], and the earliest reference I have found to Cowry-X on Bladeforums in 2001 [2]. So both of the steels have been around for some time. The fact that two companies released essentially the same product perhaps indicates that the steel was not patented, which means little information would be available about its development. Both steels have an interesting composition with 3% carbon and 20% chromium along with a few other small additions. There are a few different reported compositions for ZDP-189 in terms of the Mo, V, and W content but below is from Spyderco.
VG10 and Super Gold 2 – Takefu Stainless Steel Properties and History
Thanks to Larry Elletson, Tim Sigwarth, Steve Matthes, Curtis Seizert, Kristian Gasparius, and Will Collins for becoming Knife Steel Nerds Patreon supporters! We now have over 150 supporters!
History of VG10
Super Hard (70 Rc) High Speed Steels – Maxamet, Rex 121, and More Explained
Thanks to Roberto J. Rodriguez and J. Kelley for becoming Knife Steel Nerds Patreon supporters! We only need a few more for 150 supporters!
Super Hard High Speed Steels
The super hard high speed steels (>68 Rc or so) are interesting from the standpoint of knife enthusiasts and knifemakers, particularly since knives are so often produced in the 58-61 Rc range. The metallurgy of these types of steels is also interesting. But before we get to what exactly these steels are and how they work, it makes sense to look at what led to their development first.
Sandrin Carbide – What is it?
Thanks to Justin Anthony, Stephen Pastore, David Singer, Chester Dussault, Joseph M. Lewanowicz, Mike Opitz, Murray Fox, and Robert Hatcher for becoming Knife Steel Nerds Patreon supporters!
Cemented Carbide
Crucible S45VN Steel – Everything You Need to Know
Thanks to John Dyess, Michael Foote, Xun Fan, and Mark Vanderwest for becoming Knife Steel Nerds Patreon supporters!
Thanks to Niagara Specialty Metals for getting me a bar of S45VN for the experiments necessary for this article.
Nitro-V – Its Properties and How to Heat Treat It
Thanks to Brad Ettinger, James Henley, and Edgar Candela for becoming Knife Steel Nerds Patreon supporters!
Nitro-V Steel
Nitro-V is a stainless steel sold by New Jersey Steel Baron which was first released in 2017 [1]. The steel was designed and produced in collaboration with Buderus Steel as a version of Uddeholm AEB-L modified with nitrogen and vanadium. Another obvious comparison is with 14C28N which was designed as a version of 13C26 modified for improved corrosion resistance. 13C26 is nearly identical to AEB-L but produced by Sandvik. You can read more about the history of AEB-L, 13C26, and 14C28N in this article.
The History of Powder Metals in Damascus Steel
Gratitude
Thanks to cbw, Doug Siddens, Nick Dunham, and Robert Martin for becoming Knife Steel Nerds Patreon supporters!
I interviewed several knifemakers for this article. Thanks to Ed Schempp, Hank Knickmeyer, Steve Schwarzer, Rick Dunkerley, Jim Batson, Shane Taylor, Jeff Carlisle, Kelly Cupples, Daryl Meier, John Davis, Matt Diskin, Wade Colter, Barry Gallagher, Howard Clark, Bob Kramer, and Devin Thomas for talking to me.
H1 Steel – How it Works
Thanks to Guns N’ Loaded for becoming a Knife Steel Nerds Patreon supporter!
Austenitic Stainless Steels
At its most basic, H1 is an austenitic stainless steel. Austenitic stainless steels are about as old as stainless steel itself, being developed by German metallurgists in the approximate time period of 1909-1912. They worked on 18% Cr, 8% Ni steels which are quite similar to common austenitic stainless steels like 301, 302, and 304.
How to Pick the Best Steel for Every Knife
Update 2/19/2021: In the recommendations section I updated a few of my recommendations based on new experiments and new steels.
Thanks to Mau, Benjamin Amaral, Karolis Griskevicius, Dan Frazier, and Jess Hoffman for becoming Knife Steel Nerds Patreon supporters! We are now over 100 supporters!

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.
Thanks!
Can you tell me about AR-RPM9 please?
Thanks,
Mine S
I’ve only written about AR-RPM9 in an article exclusive to the Knife Steel Nerds Patreon.