Is M2 Steel Good For Knives?
If you’re looking for more information about how practical M2 steel is for making knives, you’ve come to the right place. With no prior experience using m2 tool steel, you can find it challenging to decide whether to trust it to make you a good knife that fits your needs and requirements.
The following post walks you through an in-depth discussion about the AISI M2 tool steel and covers important details like its chemistry, hardness, wear resistance, edge holding performance, corrosion resistance, toughness, sharpenability, and other important info you need to easily decide if this is a good steel for knives.
What Is M2 Steel?
M2 is a high-speed tool steel that features high molybdenum and tungsten content, enabling it to offer excellent hardness, wear resistance, and toughness.
This steel has been around for quite a long and Gerber, a top US knife manufacturer, was using it back in the 90s. And it has been a popular choice to the point of toppling T1 high-speed steel for use in the same applications.
However, keep in mind that the popularity of this steel went down around 2005 after it was replaced by AISI M4 high-speed tool steel which offered better hardness, toughness, and edge holding ability.
The steel capable of keeping its temper at extremely high temperatures, making it suitable for high-heat cutting jobs such as drill bits and other metal cutting equipment. For the knives, it’s mostly used to make high-end limited edition production knives as well as custom knives.
M2 Steel Chemical Composition
The M2 steel chemistry is well balanced and features high Chromium, Tungsten, and Molybdenum, making it hard steel with great corrosion resistance and toughness.
The following table shows the complete M2 tool steel composition:
Percentage composition (%)
0.85% Carbon improves the steel hardness, tensile strength, and improves wear resistance. As the amount of carbon in a steel alloy increases, the ductility trends downward.
4.15% Chromium increases tensile strength, hardness, and toughness. Since the chromium appears in low amounts, M2 is highly vulnerable to rusting and not a good steel knife for use in humid or saltwater conditions.
5.00% Molybdenum increases the hardness, strength, and toughness of this steel.
1.85% Vanadium boosts the steel toughness while increasing its strength and wear resistance.
0.280% Manganese increases the hardenability and wear resistance of this steel.
0.30% Nickel adds to the steel toughness.
0.45% Silicon improves the steel strength.
0.25% Copper helps prevent surface oxidization, thereby promoting corrosion resistance.
0.030% Phosphorous improves the machinability, strength, and hardness of M2 steel.
0.030% Sulfur boosts machinability. This element has to be used in small amounts since too much of it can increase impurity level in the steel alloy and affect its strength.
How Hard Is M2 Tool Steel?
M2 tool steel can be hardened to a Rockwell hardness of 62-65 RC. This high M2 tool steel hardness makes M2 gives the steel the ability to keep a sharp edge for a long time and offer great wear resistance.
M2 Steel Properties
With the knowledge of the m2 steel chemistry and its Rockwell hardness, we can now look at how this steel performs when used to make an M2 knife blade.
M2 Steel Edge Retention
One of the great things that make m2 steel great steel for knives is its ability to hold an edge for long—pretty much what you expect from steel made for high-speed cutting tools.
The steel’s composition promotes the formation of small, evenly distributed carbides which give the steel high wear resistance. The higher the wear resistance, the greater the edge retention performance.
You’ll be surprised that M2 steel can hold an edge better than some of the steels in the high-end steel class.
M2 Steel Toughness
M2 steel is tough stuff! Yes, it delivers high toughness for a knife blade hardened above 63HRC. This is a huge plus for this steel given that most hard steels usually feature low toughness.
The M2 steel enjoyed applications like making straight knives for planers and jointers, which proves how tough a steel it is, as these knives take tremendous shock loads that only a high toughness can be used to make them.
The steel can take droppings, batoning, and even flexing without showing signs of cracking or breaking!
M2 Steel Corrosion Resistance
The steel contains 4.15% chromium volume which means it’s not stainless steel. So, does M2 tool steel rust? Well, this steel isn’t the worst in rust resistance and still offers a considerable amount of corrosion resistance.
But don’t expect this steel to perform as well as a stainless steel. Leaving your m2 steel knife exposed to elements will cause it to rust easily, making this steel less suitable for use in the field. That said, if an m2 steel knife comes with a good finish, it does a great job at repelling rust.
M2 steel is fairly easy to sharpen. It’s not the easiest to sharpen and not the hardest either. The challenge to sharpen this knife comes from the fact that the knife features high wear/abrasion resistance.
But when you sharpen it correctly, your M2 steel knife attains a scary sharp cutting edge that it holds for really long. We also suggest that you make a habit of touching up your knife after heavy use to ensure it maintains an ultra-sharp edge.
M2 Tool Steel Machinability
M2 has a machinability rating of 50%, meaning it’s medium machinability steel in the annealed condition. The steel gives your poor grinding experience and will require a lot of effort to shape. Add to the fact that it’s challenging to sharpen, and this further makes the steel a less suitable option for knife smiths.
If you’re ready to invest in high-quality grinders and abrasives, however, you can easily get the hang of this steel and makes a good knife with it—offering all the properties we’ve just discussed above.
How Do You Heat Treat M2 Tool Steel?
M2 tool steel heat treatment involves a pre-heating before the hardening process which occurs at 2610°C (4730°F). This is then followed by rapid heating from 2610°C (4730°F) to 3960°C (7160°F).
After the heat treatment process, you should now cool your m2 steel for approx. 3 to 5 minutes and then quench it in air, salt bath, or oil.
M2 Tool Steel Equivalent And Comparison
M2 Tool Steel Vs D2
AISI D2 is close steel to M2 and is at times considered its equivalent. Not to forget, D2 is also popular in the knife manufacturing industry. When these two steels are treated to the same hardness level, M2 will offer better wear resistance and toughness. But D2 offers better corrosion resistance and is more difficult to sharpen than M2 tool steel.
M2 Vs M4 Tool Steel
As we have mentioned earlier, M4 tool steel replaced M2 around 2005. As the upgraded version of the famous M2 steel, the M4 steel delivers higher toughness at the same hardness as M2. Because of the higher carbide volume in M4 than in M2, it’s less challenging to grind, offers increases wear resistance and has better edge retention than M2 at the same hardness. However, anti-corrosion performance is still wanting for both steels.
How Good Is M2 Steel For Knives?
M2 steel will make good knife blades unless corrosion resistance is an issue for you. The steel qualifies as good knife steel because it takes a keen edge and holds it for long, has excellent wear resistance, and is a tough steel that doesn’t easily crack or break.
Due to the poor corrosion resistance, however, you shouldn’t take your m2 knife in the fields or simply humid and salty conditions like fishing, diving, hunting, or kitchen.
Benchmade and Gerber are two trusted knife manufacturers in the US who trust M2 steel to make good and reliable knives.
It is worth keeping in mind that M2 steel is unpopular in the knife makers’ community because it’s quite difficult to work. Plus, it’s expensive steel. You can get a 36-inch bar m2 tool steel for $100.
Quick Note: If M2 tool steel is such a great knife steel, then why don’t you see it in knives today? Well, the reason is that this steel was replaced by CPM M4 steel which offered improved performance in all categories except for its high pricing. You might have noticed that Gerber and Benchmade who had a handful of knives in this steel don’t seem to use it anymore.
There you have it! All the information you need to decide whether M2 tool steel is a suitable choice for knives. The strength excels in high hardness, excellent wear resistance, long-lasting edge, and great toughness. Sharpening it is also fairly easy. Its major downside is poor corrosion resistance.
If you want a high-end knife and corrosion resistance isn’t a big deal for you, then the M2 steel knife is a great choice for you. Otherwise, you should look at other steels with rust-free performance.