If you aim to manufacture knives that can tackle abrasion and wear, then it is the K390 steel that you are in search of. The famous knife-making company, Spyderco uses K390 steel for the manufacturing of EDC knives that belong to their signature series. Let us have a look at the details of properties and chemical composition that make the knife stand out in the market.
What is K390 Steel?
K390 was designed and formulated by a German knife maker called Bohler that used the steel for the construction of tools required for cold work applications and manufacturing plastics. Bohler used a special particle metallurgy process known as MicroClean technology for the manufacturing of the steel.
The K390 steel is an alloy that has been formulated to have extreme strength and great wear resistance that ensures efficient working in processes like blanking, cutting, and punching in industrial processes.
The chemical composition of K390 Steel gives it’s surface a homogenous and fine microstructure that increases the machinability and tolerance for heat treatment. Both of these characteristics of the steel ensure that it has a great amount of toughness to handle abrasion and excitement capacity of edge retention.
Chemical Composition:
The K390 steel cannot be classified as stainless as it does not have the required percentage of chromium in its chemical composition. Yet, the chemical composition consists of required elements that make K390 ideal tool steel.
- 2.47% of Carbon: Works for increasing hardness level, and increasing the resistance of the steel towards corrosion and wear.
- 4.20% of Chromium: Brings improvement to corrosion and wear resistance, edge retention and tensile strength of the steel.
- 3.80% of Molybdenum: Increases hardness level, machinability and steel strength.
- 9.00% of Vanadium: Helps in improving hardenability and wear resistance of the steel.
- 2.00% of Cobalt: Works for boosting the performance of all the elements of the steel.
- 1% of Tungsten: Increases hardness level and wear resistance of the steel.
- 0.55% of Silicon: Works for boosting steel strength.
- 0.40% of Manganese: Increases hardness level and forging ability of the steel and decreases brittleness of the steel.
The hardness of the steel:
According to the reading on the Rockwell C scale, the hardness rating of K390 steel ranges between 64 to 65 HRC. The reading states about the immense amount of hardness of the steel. Because of the hardness level of the steel, K390 has some great properties that knife makers look for to manufacture premium quality knives.
Steel Properties:
- Good Toughness: The german steel exceeded expectations when it came to toughness. For a fact, you would consider K390 to have the least amount of toughness because of having such high hardness rating. Surprisingly, K390 steel has shown great performance in terms of tackling the impact of difficult cutting jobs. The reason behind the good toughness of the steel is the MicroClean technology that Bohler used for the manufacturing of the steel. Yet, you need to be considerate and not use the steel for batoning as it can cause deformation and chipping.
- Excellent Edge Retention: High hardness level gave K390 steel excellent edge retention capability. The steel will stay sharp even after heavy duty for a long time. Furthermore, the chemical composition of the steel consists of carbon and vanadium that works for edge retention. Vanadium carbides on the surface of the steel increase the durability of the edge.
- Terrific Wear Resistance: K390 steel stands out for its terrific performance in wear resistance. The reason behind this is the high level of hardness. The chemical composition of the alloy steel consists of a high amount of vanadium that boosts wear resistance capacity. Even after years of use, you won’t notice the steel deteriorating in quality.
- Decent corrosion resistance: As the chromium percentage in K390 is way below the required amount, it is not stainless. This results in poor performance of the steel in terms of corrosion, rust and stain resistance. Yet, there is 4.2% of chromium present that does give the steel some capacity of corrosion resistance. You will need to look after the steel by keeping away moisture from the surface.
- Ease of Sharpening: Due to the high hardness level of K390 it is not easy to sharpen. Yet, it is not like the knife made out of steel goes useless once the sharpness is lost. All you will need is a high-quality sharpener with the right type of abrasives for giving the edge a proper finish. Getting a diamond stone is what we recommend for keeping the sharpness of the knife well maintained.
Comparing K390 With Other Knife Steel Options:
K390 vs. S90V
K390 is similar to S90V due to the great performance of the steel in terms of edge retention, toughness and hardness level. Both of the steels have similar properties because of the presence of vanadium in the same percentage in their chemical composition. The cost of both the steels is the same. The only difference between them is that S90V is stainless with enough chromium percentage for corrosion resistance.
K390 vs. VG10
VG10 beats K390 steel in terms of resisting corrosion, ease of sharpening and toughness level. But K390 has a great hardness rating which makes it better in edge retention and wear resistance compared to VG10.
K390 vs. M390
M390 is stainless and on the other hand, K390 is not, which causes K390 to lose corrosion resistance. Furthermore, M390 beats K390 in terms of toughness and ease of sharpening. But K390 wins over K390 in terms of edge retention and wear resistance due to its high hardness level.
So, is K390 Steel Good?
If you are looking forward to manufacturing a knife with great edge retention capability and terrific resistance to wear then you can consider K390 good knife steel. But you will not find satisfaction in the steel in corrosion resistance. For that maintenance is required and you will need to keep the steel away from humidity and moisture.