Stainless San-Mai ApexUltra Knife Making Steel Billet

Hand-forged San-Mai knife making steel billet.

ApexUltra carbon steel core and 420 stainless clad with nickel. Please select a size from the drop-down box. 

ApexUltra is a low alloy steel specifically designed for handmade knives. It features fine carbides that make it easy to finish and sharpen, and its high purity and well-balanced composition result in exceptional toughness and edge retention. This steel is said to be the toughest of all knife steels in the 66+ HRC range.

These billets are intended to be ground to shape, perfect for stock removal makers in pursue of the character you get from hand forged steel, the pattern and the texture that pre laminate steel usually doesn't have. I like to keep the texture on the flats as you can see from the sample pictures but with care to grind symmetrically, it can be flattened. They come as forged and slightly oversize, you will need to grind the edge of the billet back to good material.

All our billets are forged in a zero-atmosphere environment to ensure perfect welds. We pride ourselves in well-centred cores, consistent patterning, and excellent quality steel.

Once heat treated, ground and etched, the cutting edge will be black followed by a bright nickel line and then a beautiful carbon migration pattern into the lighter colour stainless. As you can see from the sample pictures, the look can be changed with different polishing and etching processes. Please take a look at the using our billets page for more info and feel free to email if you have any questions.

These billets have been annealed and can be drilled with decent hss drills although we’d recommend carbide-tipped drills.

Heat treat info for ApexUltra billets:

We offer a heat treat service, please contact us if needed. Heat treat with other companies at your own risk. 

Please note stainless clad billets are a little more sensitive in heat treat than the Dark-mai so extra care must be taken to avoid cracks along the core. We recommend bevelling to a point all the way around at 45 degrees, sanded perpendicular to the blade NOT along the length. Bevelling the edges will reduce the force pulling directly on the core while the austenite to martensite transformation is occurring in the 80crv2. 

Normalize by heating to 950c for 15 minutes and let cool to room temp in air. A grain refining cycle is also recommended; heat to 790c and air cool. Quench at 850c in medium quench oil after a 10-15 minute hold at temp. Temper for 2 x 2-hour cycles at 160-240c for 66-63 HRC.

This steel has good toughness and should be durable even at this hardness. Please note these instructions are just guidelines. We recommend testing your finished products to ensure the best results are achieved. There is a lot of information on the knifesteelnerds website.