Showing posts with label Larrin Thomas. Show all posts
Showing posts with label Larrin Thomas. Show all posts

Sunday, January 21, 2024

Magnificent MagnaCut

 

Crucible Powdered Metal’s MagnaCut steel is, perhaps the best performance steel on the market.  It is certainly the hottest!

Dr. Larrin Thomas, its inventor, thought there should be a steel that could be optimized to give small grain steel with tiny, supper hard carbides capable of reaching Rockwell 60+ hardness without brittleness and still be rust resistant.

I’ve taken a very short step in to metallurgy and perhaps the first thing you learn is you simply can’t throw elements into a pot and get a great outcome.  Metallurgy is complicated, heat treatment is a specialty, and you just don’t plunge a red-hot knife from the forge into oil and get a great outcome.

MagnaCut was the result of serious study and testing which culminated with a single hit or miss lot of steel.  Larrin got one bite at the apple and he was successful.  The story of its development is here: https://knifesteelnerds.com/2021/03/25/cpm-magnacut


One of Spyderco's MagnaCut folders: 

Let me be honest with you.  The article is written for steel nerds, people who enjoy technical data, like hard science fiction and enjoy reading about science.  I’m one of them.

The upshot is MagnaCut, due to its properties, when processed properly is an amazing steel.  The high-end knife makers jumped on it like white on rice.  This quickly worked its way down to EDC knives.

You can Google MagnaCut and any knife company and get a hit.

Here’s the formulation: Carbon 1.15%, Chromium 10.7%, Vanadium 4.00%, Molybdenum 2.00%, Niobium 2.00%, Nitrogen 0.20%.


Kershaw Launch 4 in MagnaCut

The amazing thing, all the chromium is available for corrosion resistance.  The  carbides are all vanadium and niobium.

We could talk about Charpy C-notch test, Edge Retention (CATRA Testing Relative to 440C), salt spray corrosion test, but you can find that yourself.  The important thing is to realize this steel helps makers use a better blade geometry for improved cutting while ensuring extended performance.  And while performance doesn’t come cheap, this steel is worth it!

Bestech's Swordfish in Magnacut

You’re going to see a lot of MagnaCut in the future.

Friday, June 3, 2022

Blade Show 2022 Day One

 The Blade Show 2022 opened with its usual whimper.  Neither Cobb Galleria nor the people from Blade are unable to figure out how to handle the crowds.  The Customer Appreciation Passes were not available until 10 am this morning, and the Show opened to us at 11:00 ~ a LONG line to get in the building and then another line (they called out last name letters alphabetically!) to get the actual badge!  It would have been much simpler if the CAP passes were available Thursday afternoon/evening, then anyone could have picked them up at their convenience.  

This was the line in front of us, and we were 1.5 hours early!

The line standing in the Georgia sun would have been much more manageable.  Still, I was able to pick up my pass and make it to my 10:30 class on Cryo-Quenching.

The class was run by Larrin Thomas, a Ph.D. in metallurgy who works in the automotive industry.  Perhaps more importantly, he is the inventor of MagnaCut, the new hot steel everyone is going crazy over.  

Larrin and carbide grain sizes with SEM

I have a lot of notes, but perhaps the most interesting is the rate of converting austenite into martensite occurs at the speed of sound.  It isn’t a chemical diffusion process, so it also happens at liquid nitrogen temperatures.  After an hour of graphs, images, and explanations, I’m still a little confused.  It reinforced how complex carbide size and location, metal crystal phase, and time is to temper a steel blade.  I’ve said it before, the heart of a knife may be the blade, but the soul is the heat treatment.

Many foreign companies were in attendance this year, Covid restrictions have lessened and countries are allowing overseas travel.  One of my favorite overseas visitors is Grace Horne.  She’s been making scissors for the last couple of years, and she sells out almost instantly.  Fortunately, some of the buyers let her display some of her scissors so you could see them.

Perhaps the most exciting news for me was the release of Rick Hinderer’s new automatic knife, the XM-18.  I’ve waited since April of 2021 for this hot puppy and it is finally here.  Rick is celebrating his 35 years as well. 

Here are a bunch of photos for your consideration.


Hinderer's new auto Just released at Blade Show


Santa Fe Stone Works


CRKT's new SPEC   I really liked the handle!


CRKT's Curfew   The white portion of the handle has an Ivory feel, but it is not


Engraving


Not every knife is what you call practical


This Chili Pepper is coming home with us - by Kizer


Winkler Knives


Italian knives from MKM designed by Jesper Voxnaes





The last two from Grace Horne  Who says scissors are boring?