From Spyderco
Manufactured by Böhler-Uddeholm, K390 MICROCLEAN is a state-of-the-art cold work tool steel produced by the particle metallurgy process. Its advanced alloy mix was specifically developed to provide the extreme wear resistance and high compressive strength needed in industrial cutting, blanking, and punching operations.
Despite its toughness, its exceptionally fine, homogeneous microstructure also makes it readily machinable and easy to heat treat. Collectively, these qualities make K390 an outstanding blade steel. The exact alloy composition of K390 is as follows: Carbon: 2.47%, Chromium: 4.2%, Cobalt: 2.0 %, Manganese: 0.4%, Molybdenum: 3.8%, Silicon: 0.55%, Tungsten: 1.00%, and Vanadium: 9.00%. Please note that K390’s limited Chromium content makes it a true tool steel—not a stainless steel—and ensure that you care for it properly.
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