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Blade smithing

I looked up the use of dry ice for blade cryo treatment, and most people just create a dry ice bath using alcohol or acetone mixed with dry ice to transfer the heat from the blade more evenly.
 
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I finished my meat carving knife forged out off the new CPM magnacut. In comparison to some high performance steel like cpm 4v with high vanadium, the powder metallurgy and slightly lower level of chromium gives it higher corrosion resistance along with the balance of high hardness and toughness.
The handle I made from some custom scales I found on etsy made of resin.
 
I followed the best heat treatment given by Larrin Thomas, the designer of the metal. I used plate quenching to prevent the thin 12 gauge blade from warping.
 
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I've now furnished the bowie knife that I began working on before my meat carving knife. This blade was also made out of CPM magnacut, for the performance as a hunting knife or survival knife. The edge is extremely sharp, and slices through wood just like a swiss made carving knife. The balanced hardness and toughness of the steel makes it work well for chopping wood as well. I am pretty confident that the heat treatment was very successful, and that the cryo treatment simply with our deep freezer made a difference to. This time I found a way to polish the hard stainless blade to a mirror finish, using very fine sanding discs with my angle grinder instead of polishing compound.
When ever I make a certain knife for the first time, I feel determined to do my very best. With all my creativity I decided to make it more decorative. I acid etched a flame pattern into the blade face, I shaped the brass ring guard inserted into the fiberglass handle, and added another dragon pommel. Though all this work can create a beautiful knife, it makes it worth so much more than someone would pay for a bowie knife. There are some magnacut knives online that are sold for over $600 which could be acceptable for this blade; however people would buy this more as an ornamental peice of art.
 
I did some more research on cryogenic treatment of alloy steels in LN vs dry ice, and it turned out that the difference in hardness between steel cryo treated in LN vs dry ice would make it worth purchasing a dewar for LN. I got a 3L dewar from Vevor for 200 dollars, but it comes empty, where could I get it filled?
 
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I contacted praxair which is Linde now, and the cost for only 4.5 L of LN is $180! I'm not sure how long only 4.5L would last, and if it be worth the cost of $180.
 
You supply your own. The dewar I got from Vevor is only 3L, and I was unaware that the minimum they can fill is 4.5L, so I'll probably have to get a 6L dewar, and find a way to influence Vevor to allow me to return the 3L dewar.
 
The handle is made of synthetic layered fiberglass. The different colored layers create a pattern as you round the edges. I don't know what steel was used, but most forged blades are made from low alloy carbon steel which have much lower properties/ rankings than tool steels, and high carbon stainless steels which make up higher quality knives.
 
Chris Cramer said:
The handle is made of synthetic layered fiberglass. The different colored layers create a pattern as you round the edges. I don't know what steel was used, but most forged blades are made from low alloy carbon steel which have much lower properties/ rankings than tool steels, and high carbon stainless steels which make up higher quality knives.
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Care to explain that further?

Lower hardness blades are easier to sharpen, require more often sharpening

Higher hardness run the risk of being too brittle

Is there a happy medium ?
 
The general rule of thumb is higher hardness means lower toughness, but over the years there have been discoveries that have engineered steels with balanced properties of hardness, toughness, and corrosion resistance. Those are the three general metal properties. Standard high carbon low alloy steels that are easiest to forge such as 1084, 1095, and 15n20 have decent toughness but low hardenability because the hardness comes ony from added carbon. The added carbon creates iron carbide which is the softest type of carbide.
High alloy tool steels contain alloys that provide more hardenability. High alloy steels with high Vanadium and tungsten fall under high speed steels because Vanadium carbides and tungsten xarbides are the hardest types of carbide
One of the biggest inventions that has brought more toughness into extremely hard steels is powder metallurgy. Powdered metallurgy technology reduces the size of the carbides in the carbide structure of the steel. In return, the fine carbide structure makes the steel much tougher.
If you look up knife steel ratings on Google and go to knife steel nerds, you can read an excellent article about different ratings and some tables on the ratings of different steels.

Moderator Edit - I think this is what you wanted us to see. https://knifesteelnerds.com/2021/10...ness-edge-retention-and-corrosion-resistance/
 
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Everything I just explained is metallurgy. The metallurgy will make a big difference on the machinability of the blade, but when you talk about bladesmithing, geometry of the bevel and the edge makes more difference on edge retention and toughness than the metal and heat treatment.
 
Years ago I was in the sport of Fencing, Epee in particular and was looking a manufacturing Competition blades here in Canada (this is part in parcel that got me hooked up with one of my mentors in metal working).

The Steel of choice is Maraging 250, because of strength, hardness, flexibility, durability, corrosion resistant and most importantly when it fails it breaks clean (no ice pick failures, important to prevent injuries or death). What is it Russian Aircraft landing gear steel (MIG). Expensive to say the least. Additionally it uses a Mar-aging process (cold treatment to achieve martinized metal lattice in the structure).

I also found and considered Aeromet which comes in flavours Aeromet 100 and Aeromet tool steel (this version is a lot cheaper because it does have the addition boxes of paperwork for military certification. What was it designed for you ask, landing gear, particularly for the new fighters at the time in development the F35 and F22.

I'm in agreement with @Chris Cramer metallurgy, design and treatment achieve the best result for toughness and durability, look and finish that is skill and artistry (of which the latter is hit and miss for me).
 
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