65Mn steel is made in China and belongs to the spring steel family. It is also among the toughest Chinese steel. It features Carbon and Manganese as its primary components. Most manufacturers refer to it as 65Mn spring steel.
The MN in its name represents Manganese that improves the hardness, giving 65Mn high hardness and excellent wear resistance.
The carbon and manganese mixture contributes to high toughness making this steel ideal for making large blade knives, machetes, sword blades, clockwork, shock absorbers, round springs, and brake springs, to mention a few.
65Mn Steel Chemical composition
- Carbon C 0.71%: Increases the edge retention, hardness and tensile strength. It also improves steel resistance to wear, abrasion and corrosion.
- Chromium Cr 0.25%: Chromium Increases hardness, tensile strength and corrosion resistance of a blade.
- Manganese Mn 1.10%: Increases hardness of the steel
- Silicon Si 0.37%: Increases strength and heat resistance.
- Sulfur S 0.05%: Improves machinability
- Phosphorous P 0.04% :
Properties of 65Mn steel
65Mn Carbon steel hardness is between 28-34 HRC according to Rockwell hardness which is a bit low compared to other types of hard steel available. The hardness is mainly dependent on the heat treatment applied by the manufacturer.
However, with the low hardness comes outstanding toughness meaning that the knives and other products made from this steel do not break easily.
As a rule with steel, the harder it is, the lower its toughness. With that in mind, we can conclude that 65Mn offers excellent toughness because it is low in hardness.
Carbon, Manganese, and chromium in their composition are associated with good levels of toughness.
Working with 65Mn High Carbon steel knives gives you confidence that they will not break or chip during tough applications.
The wear resistance of 65Mn is considered okay. In the world of steel and knives, the level of wear resistance is associated with hardness. Since 65Mn has low hardness, we cannot expect its knives to last for years.
The Carbon in its composition enhances the wear resistance.
Another property affected by the hardness is edge retention. You can already tell that this steel has poor edge retention because of its low hardness levels.
Compared to other steels with the lowest hardness as 50 HRC, 65Mn blade cannot stay sharp for long, with its highest hardness as 34HRC.
For that matter, your 65mn knives will become dull faster and require frequent sharpening.
65 Mn Steel does not have enough chromium in its composition to make it stainless steel. Therefore, it has relatively poor corrosion resistance.
Because of the inability to resist rust and corrosion, 65Mn steel is not used to make diving and kitchen knives because they are used in humid and wet environments, encouraging rusting.
With this realization, knife makers add an anti-rust coating to knife blade made from this steel to protect them from rusting.
65Mn Carbon steel is easy to sharpen because it is not very hard. It is a good thing that it is easy to sharpen because it loses edge faster.
It will not be a challenge to get a sharp edge on 65mn knives, the many times you will be required to sharpen them.
65Mn steel equivalents
65Mn vs. 1095
The first main difference is that, 1095 steel is made in the US while 65mn is made in China. Due to high amounts of Carbon Content in 1095, it offers high hardness, better edge retention, and wear retention.
On the other hand, 65Mn is better in corrosion resistance, and it is easier to sharpen.
65Mn vs. 8Cr13MoV
8Cr13MoV Steel contains more Carbon than 65Mn hence better in hardness, edge retention, and wear resistance.
65Mn steel knife beats 8Cr13MoV in toughness because it does not have a lot of Carbon.
Furthermore, 8Cr13MoV is stainless steel with high chromium contents, giving it better corrosion resistance than 65Mn.
Is 65Mn good knife steel ?
65Mn steel is a good knife steel but not the best, it offer great toughness but has low hardness and poor corrosion resistance. It will be a good choice for a batoning knife, machete knives, but a bad choice for applications in wet, humid and salty environments.
You would want to dismiss 65Mn from the list of good knife steels, assuming that it is poor quality because it is made in China, but that is not the case. 65Mn is a good steel for knives because it offers excellent toughness and good wear retention.
Knives made from this steel will last longer and handle tough applications like batoning without breaking or chipping. However, I would not recommend 65Mn steel for Chefs, divers and hunters. It’s poor corrosion resistance will always need extra care for such applications.