What is k390 Steel Used For?

K390 steel is a type of steel known for its high resistance and durability. It is excellent for making knives, blanking, and cutting. It is not stainless, has hardness of 65 hrc, is similar to S90V steel. It is made by Böhler-Uddeholm.

Note that a hrc above 59 is generally considered premium.

k390 is known for making knives because of rust and corrosion resistance, and of how hard the steel is. Some examle products that use are the Spyderco Ladybug 3 Lightweight Folding Knife and the Arcform Slimfoot Frame Lock Knife Ti/Carbon Fiber 3.3″ Stonewash.


Carbon: This enables the steel to be resistant to corrosion. It also adds to the hard nature of the metal. It makes 2.47% of the steel.

Chromium: Added because of its ability to retain the edge of the steel and for tensile strength. It also increases the corrosion resistance by 4.25%.

Molybdenum: Contributes to the strength of the K390 steel metal. It also adds on the machinability as it comprises 3.8% of the metal.

Manganese: Makes up 0.4% of the metal, contributing to its hard and brittle nature.

Silicon: Makes up 0.55%, and it’s also for hardness and strength.

Vanadium: Comprises of 9%, which highly contributes to the hard nature of the steel. Also, vanadium resists wearing.

Cobalt: Makes up 2% and contributes to the efficiency of the other components.

Tungsten, 1%: Added to increase its ability to resist wearing and also for hardness.



The steel is made up of various features with hardness standing out. As per the manufacturer, the hardness in k390 can go up to 65HRC. Let’s explore some of the features that make this type of steel to be of high quality.

Resists corrosion

This is due to the existence of Chromium, standing at 4.25 %.

Wear Resistance

With the presence of vanadium, the metal can stay up to five years without any signs of wear.

Edge retention

The knives are made from k390 and know to be durable because of this. Without the ability to retain an edge, a knife dismantles when subjected to a hard object. Chromium, Carbon, Molybdenum, and vanadium have highly contributed to the high edge of this particular steel.

Compare to other types:

65mn Carbon

Other features include toughness, sharpness, and even machinability so that is why it so often used for making knives