Category: Heat Treating and Processing

3 thoughts on “Heat Treating and Processing”

  3. Ciao Larrin,trovo molto utile questo sito,
    Avrei una domanda riguardo all’acciaio A8mod:come é meglio temprarlo per raggiungere la massima durezza?

    Reply

Leave a Reply

Your email address will not be published. Required fields are marked *

Damascus, Powder Metallurgy

The History of Powder Metals in Damascus Steel

Larrin

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. read more

Forging

Forged vs Stock Removal Knives

Larrin

Thanks to Colin Fergus and funny_name_here for becoming Knife Steel Nerds Patreon supporters!

Forging by the Steel Company vs Bladesmith

When the steel company makes the steel they produce a large melt of the steel with the desired composition and pour it into a mold which solidifies and produces an ingot. A typical ingot size for tool steel or high speed steel might be 10″ thick either round or square depending on the production process and the desired final shape. Smaller ingots are better for limiting the segregation of alloying elements and keeping the cast structure fine. At that point the steel is in “cast” form. The ingot is then heated up to high temperature and forged either with a hammer or press to a form ready for hot rolling. In some cases the ingot is ready for rolling as-produced. Next the steel is hot rolled to the final desired thickness. Hot rolling in an industrial setting is typically done with relatively few reheats, typically single digits. That depends on how much reduction in necessary, how difficult the steel is to work, and the capability of the rolling mill. read more

Austempering, Austenitizing, History - Articles - Books

The Secret Heat Treatment of Frank J. Richtig

Larrin

Thanks to Dean Baughman, Kitoc420, Steve Callari, Jay Ghoo, and Mitch Cagile for becoming Knife Steel Nerds Patreon supporters!

Legendary Heat Treatments

Last week I wrote about What a Good Heat Treatment Can and Cannot Do, and as part of that topic I wrote about how some knifemakers have a legendary or even mythical reputation for their heat treatments. In that article I argued that the big differences are between “bad” and “good” heat treatments, and that the differences between various good heat treatments are much smaller. And that edge geometry and knife design are more important to knife performance than the differences that are possible between different “good” heat treatments. So I think it makes sense to discuss a particular case of a knifemaker known for legendary, unmatched heat treatments, which brings me to… read more

Heat Treating and Processing

What a Good Heat Treatment Can and Cannot Do

Larrin

Thanks to C6 MFG and Dan Swaney for becoming Knife Steel Nerds Patreon supporters!

The Legend of Heat Treatment

There is some debate about knives that have steel with a “good heat treatment” vs those that have a bad or sub-par heat treatment. Some knifemakers have a near legendary reputation for their excellent heat treatments. What exactly is possible in terms of heat treating? How much better can steel be? How bad can it get? read more

Annealing

How Annealing of Steel Works – Subcritical vs Transformation Annealing

Larrin

Thanks to Larry Corsa and Gene Kimmi for becoming Knife Steel Nerds Patreon supporters!

Why Anneal?

There are three primary goals of annealing steel:

  1. Make the steel machinable so that it can be easily cut, drilled, and ground.
  2. Setup the steel for austenitizing and quenching (hardening) so that is has good heat treating response
  3. Provide the best possible properties in the final heat treated product

The above goals are not always 100% compatible, but we would like to offer the optimal combination based on our priorities. However, to know what the trade-offs are we need to know how annealing works first. read more

Austenitizing, Heat Treating and Processing, Toughness

How to Heat Treat 52100

Larrin

Thanks to Lev Serebryakov for becoming a Knife Steel Nerds Patreon supporter!

52100 Steel

I previously wrote about the history and properties of 52100 in this article. The steel has been around since 1905, has been known as 52100 since 1919, and has been used in knives since at least the 1940’s. It was developed for bearings and its common use in bearings meant it has been a ready source for knife steel for decades. It is known for its fine carbide size and good toughness. The chromium addition compared with the chromium-free 1095 means that it has somewhat higher hardenability so it is easier to harden in oil and obtain full hardness. The chromium also helps keep the carbide size small. The chromium also shifts up the temperatures required for hardening. read more

Forging

Which Steels are Easiest (and Most Difficult) to Forge?

Larrin

Thanks to Richard Airey for becoming a Knife Steel Nerds Patreon supporter!

Forging Steel

Typically forging bladesmiths have restricted their steel selection to low alloy steels like 1095, 1084, 5160, 52100, O1, etc. There are a variety of reasons given for why the bladesmiths usually use these relatively simple steels. Often “ease in heat treatment” is a common one. However, this article will focus on which steels are physically more difficult to deform with the hammer and which crack most readily. What controls “forgeability” or steel? read more