425M steel is well known amongst knife manufacturers for making buck knives. Other than buck knives, the steel is used for the making of other varieties as well by various knife-making companies. We are going to explore the details regarding the chemical composition and various other properties of the steel.


What is 425M Steel?

Buck is the knife-making company that came up with the formula of 425M steel which can be classified as martensitic stainless steel that is of a low-end quality. 425M belongs to the 400 steel series that is well known amongst knife makers to have high corrosion resistance and ease of sharpness.


Buck knives were previously made using 440C steel during the 1960s. However, blades made out of 440C did not have satisfying edge retention causing the sharpness to fade very quickly after use. The reason behind low edge retention is because of the presence of large carbides.


To eliminate the shortage of 440C steel, Buck modified the chemical composition by homogenization to create 425M which ensures it has more fine carbides for better edge retention. 425M has a chemical composition that is closely related to popular steels like 440A, 420HC, and 12C27 sheets of steel.


With the help of heat treatment, you can easily improve the steel strength and wear resistance of 425M. But you cannot expect a high amount of hardness which makes knife manufacturers classify 425M as low-end steel. You can use 425M steel for the manufacturing of affordable knives, high corrosion resistant blades and cutting tools as well.


Chemical Composition: 

You can grade 425M steel as stainless steel because the percentage of chromium in it is more than the required amount for a steel to be stainless. We have listed down below elements in their chemical composition and their corresponding functions.

  • 0.4-0.54% of Carbon: Increases hardness level and resistance of the steel towards corrosion, wear and tear.
  • 13-15% of Chromium: Improves edge retention, tensile strength, toughness level, corrosion and wear resistance.
  • 0.6-1.0% of Molybdenum: Helps in increasing hardenability, hardness and toughness level.
  • 0.8% of Silicon: Increases corrosion resistance and steel strength.
  • 0.5% of Manganese: Aids to increase hardenability, steel strength and wear resistance.
  • 0.1% of Vanadium: Raises the toughness level, steel strength and wear resistance.
  • 0.04% of Phosphorus: Boosts the hardness level, machinability and steel strength.
  • 0.03% of Sulfur: Brings improvement to the machinability of the steel.


The hardness of the steel: 

According to the reading on the Rockwell C scale, the hardness rating of 425M is between 57 to 60 HRC. The hardness rating can vary depending on the heat treatment provided to the steel. The steel cannot be considered to have a very high hard hardness level since it does not cross 61 HRC. However, you can still consider the hardness level to be adequate because of the presence of elements like carbon, chromium and molybdenum in its chemical composition.


Steel Properties: 

  • Good Toughness: As you have seen that the hardness rating of 425M steel is below 61 HRC, which signifies low hardness, the toughness level of the steel gets a boost. That is because hardness and toughness are indirectly proportional to each other. However, the toughness level of 425M does not beat a lot of high-end steels popular in the market. Yet, the toughness of the steel is enough to take on some impact.
  • Decent Wear Resistance: The percentage of carbon in 425M is not in the amount that you see in high-end steels. Yet the percentage of carbon in 425M provides the required hardness for the manufacturing of affordable knives. Since the hardness level is not at the best, the steel thus possesses decent wear resistance.
  • Okay Edge Retention: For edge retention, steel has to have an adequate amount of chromium carbides in them. 425M steel has a high percentage of chromium but a low percentage of carbon resulting in less formation of chromium carbides and more chromium remains for corrosion resistance and just satisfactory edge retaining capability.
  • Excellent Corrosion Resistance: This property makes 425M shine in the market. The steel is capable of showing excellent corrosion resistance because of having high chromium which goes above 13%. The steel can tackle corrosion and rust even while it is being used in humid conditions.
  • Ease of Sharpening: As 425M does not have a high hardness level, it is very easy to sharpen. With the help of any usual knife sharpener, you can give the blade a sharp edge very quickly.


Comparing 425M Steel With Other Knife Steel Options: 


425M vs 420

The percentage of carbon and chromium in 425M is higher compared to 420, which results in 425M having a greater hardness level. Furthermore, 425M also beats 420 in terms of corrosion and wear resistance because of the modified chemical composition. In terms of toughness, 420 wins over 425M. Both of these steels are affordable and used for manufacturing low-end knives.


425M vs 440C

440C consists of a higher percentage of carbon compared to 425M, which makes 440C have an absence of all the lackings you get to see in 425M. Because of the greater hardness level in 440C, it is less easy to sharpen compared to 425M.


So, is 425M a Good Knife Steel?

Yes, you can consider 425M good knife steel if you are looking forward to manufacturing a knife that is capable of keeping corrosion and rust at bay while working under humid conditions. The only setback of the steel is its inability of heavy duty due to decent wear resistance and weak edge retention.



Write A Comment Cancel Reply