Austenitizing, Quenching, Tempering, Toughness

How to Heat Treat 8670

Thanks to George Walton, Josh Perdue, Bill Fitzgerald, and Donovan Phillips for becoming Knife Steel Nerds Patreon supporters!

Podcasts

I appeared on two podcasts this past week, Knife Perspective and Mark of the Maker. Knife Perspective I had been on before so we mostly focused on MagnaCut and other topics. Mark of the Maker was a full interview asking about my background before discussing my book, website, and CPM MagnaCut. So listen to one or the other or both depending on what you’re in the mood for. read more

Annealing, Austenitizing, Forging, Heat Treating and Processing, Quenching, Tempering

How to Use a Steel Datasheet to Develop a Heat Treatment

Thanks to David Reem, Colton, camilo, Brendan Gildea, Vince Koacz, Monery Custom Cutlery, Curt E, Shannon Sanders, Brazilian Blades, Rory Kelly, Brunhard, Zachary Chumley, Noel, Adam Nolte, Gundam lupus, and Jan Huch for becoming Knife Steel Nerds Patreon supporters! I still don’t know when it will be time for the announcement of my new steel so until then you can get all of the data on its properties exclusively on Patreon. read more

Hardenability, Quenching

How Fast Do You Have to Quench? Hardenability of Steel

Thanks to Richard Patterson, Patrick Guignot, Aaron Lee, and David Richardson for becoming Knife Steel Nerds Patreon supporters!

Hardenability

How fast one must quench steel is controlled by its hardenability. Hardenability is not a measure of how hard a steel can get. Instead it is a measure of how fast you have to quench to achieve max hardness for a given composition. Therefore a steel with 0.2% carbon can have high hardenability without being able to reach a particularly high hardness; the steel can be allowed to cool in air and achieve more or less the same hardness as when it is quenched in water. On the other hand, a steel with very high carbon content that can reach very high hardness can have low hardenability, requiring a water quench to achieve its potential hardness. read more

Metallurgy Principles, Quenching

What Makes Quenched Steel so Hard?

Update: I have started a Patreon page to fund research projects which you can read about here – http://knifesteelnerds.com/how-you-can-help/

To harden steel you heat it up to high temperature to form a phase called austenite, followed by rapid quenching to make a very strong phase called martensite. Hardness is a measure of strength. I covered the process of austenite formation in the following post: Austenitizing Part 1. To summarize that post: read more