AISI M2 steel or just M2 steel is a steel gaining popularity steadily. This high-alloy steel is quickly gaining traction because of how versatile it is. Many call M2 high-speed steel. M2 is high-alloy steel as well, fortified with high amounts of vanadium and molybdenum.
We’re going to take you through all of the vital information about M2 steel and pay attention to how it is different from other types of steel. We’re also going to look at how it performs when turned into and used as a knife.
M2 is one of those steels that performs well in almost every category (hardness, toughness, edge retention, ease of sharpening, corrosion resistance) and can be considered all-rounder steel.
What is M2 Stainless Steel?
M2 is a high-speed steel. High-speed steels are the best for ‘cutting’ actions, as they can do so with ease compared to other steels. M2 is a premium, high-end steel made by Crucible Particle Metallurgy.
You might have heard of M2 being used in the 90s, but it no longer was the steel of choice after replacing it with another steel in the same line: M4 with similar capabilities. However, we’re now witnessing M2 steel make a comeback.
This premium steel isn’t just used for high-end knives. It’s also used for durable fittings, castings, and broach inserts. M2 is most commonly used for screws, bolts, and nails due to its durability and performance. You’ll also find M2 used for highly specific custom knives in the market for the real knife connoisseur.
What is the Composition of M2 Steel?
M2 steel is a high-carbon, high-alloy steel with lots of different capabilities. It’s generally considered premium steel and can deliver high performance in lots of various applications. To understand why M2 can outperform other competitor steels, we must understand what the composition of M2 steels is.
The percentage blend of different elements that come together to make M2 steel is ultimately what makes it what it is. Let’s find out what goes into M2 steel:
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We’re going to examine each element’s role in the M2 steel’s final product because each element plays an important role and serves a different purpose to M2 steel and its properties.
- Carbon 0.85% – It’s important to realize that this amount of carbon is relatively high, and as a result, M2 is considered high-carbon steel. Anything above 0.50% is usually considered a high amount of carbon, so you can understand why M2 has a high carbide amount at 1.42%. Carbon contributes to the hardness of the knife blade but also plays a role in edge retention.
- Chromium 4.15% – Chromium plays two crucial roles when added to steel. Primarily, it contributes to the corrosion resistance of the knife. 4% is enough chromium content for the M2 steel to have stainless steel properties and resist rust. The dual role of Chromium is to fortify the strength of the steel. Chromium is the second hardest steel in the world, and it increases the hardness of whichever steel its added to.
- Molybdenum 5.00% – Molybdenum plays an essential role in how hard the steel is and its internal strength. 5.25% is a very high percentage of molybdenum and M2 steel benefits from this addition. You can attribute the exceptional hardness and toughness of the M2 steel to its high amount of molybdenum.
- Vanadium 1.85% – Vanadium has a triple impact on the hardness, toughness, and wear resistance of the steel? How? Vanadium impacts the grain structure of the steel itself. The power of Vanadium is one of the reasons why it’s so common as an alloy.
- Tungsten 6.15% – This high percentage of tungsten is added to M2 steel to increase its melting temperature. Increasing the melting temperature improves the heat processes and treatments that are possible for M2 steel.
- Manganese 0.280% – Manganese contributes towards the machinability of M2 and makes it more brittle.
- Nickel 0.30% – Did you know that nickel is mainly used for the production of stainless steel knives? That’s because nickel has an incredible effect in increasing the ductility of the stainless steel M2. The ductility makes it much easier to work with and shape to form great knives.
- Silicon 0.45% – Silicon is deoxidizing during the heating process of making M2 steel.
- Phosphorus 0.30% – 0.30% might appear to be a minor amount, and you’re right. However, this small amount of phosphorus is more than enough to contribute to the M2 steel’s structural integrity and internal strength.
- Sulfur 0.30% – Sulfur also plays an important role in increasing the machinability of M2 steel.
As you can see, M2 is high-carbon steel, with higher amounts of other alloying elements.
How Hard is M2 Steel?
Looking at the composition table, it’s easy to see that M2 has high carbon content, and that’s why it will have a high hardness. You can expect to have 62-65 HRC on the Rockwell Hardness Scale for an M2 steel knife.
However, carbon cannot walk away with sole hardness credit for M2. Most of the added alloys, particularly molybdenum and vanadium, contribute mainly to the hardness and edge retention of M2 steel.
Since M2 and M4 steels are often compared to each other, it’s worth noting that M2 has more hardness than M2 steel.
M2 Steel can also be at 63.5 HRC, according to the data published by CPM (Crucible Particle Metallurgy).
What is the Heat Treatment of M2 Steel?
M2 must undergo several processes of heat treatment to achieve the necessary level of hardness. These heat treatments are also required to preserve the other properties present in the steel.
M2 is preheated to 1450-1550°F (788-843°C) before it undergoes any further heat treatment techniques.
Quenching also takes place for M2 steel. Quenching is the heating process by which the steel is heated and then cooled down. It’s important to note that the temperature at the steel is heated extremely high. Once the steel has been heated to the appropriate temperature, it is cooled down into a liquid in a controlled setting. The liquid used to cool the steel down can be either regular water, a saline solution, or oil.
M2 can be quenched in gas as well, and this also gives desirable results in hardness and internal strength. If M2 is being quenched in gas, it should be rapidly heated to 1000°F (538°C). If quenched in saline water, it should be brought to 1000-1100°F (538-593°C) and then equalized. Quenched in oil can handle slightly lower temperatures.
After preheating, M2 steel can be austenitized between 2200-2250°F (1204-1232°C) in a furnace.
What are M2 Properties?
You might be wondering what M2 steel can do as a metal.
As high-carbon high-alloy steel, M2 is very different from some of the other stainless steel options out there.
It is important to remember that when buying a knife, you must be aware of the knife’s steel properties. There might be some properties of the knife that matter to you more than the others. Additionally, you might be willing to look past certain weaknesses of the M2 steel, while others are important to you.
Now, let’s look more closely at the various properties of the M2 steel and how knives built from it are affected by said properties.
The hardness of the M2 steel is extremely high. Its HRC rating can range from 62-65, depending on who the manufacturer is and what heat processes were followed during M2’s production. It’s wonderful to have a steel with such a high level of hardness, and this definitely means it will work well as an outdoor survival knife. However, if you’re going to be using an M2 kitchen knife, keep in mind that this level of hardness will scratch and scar wooden cutting boards. We recommend that you use rubber cutting boards if you’re planning to use a knife above 60 HRC in the Rockwell Hardness Scale, such as M2.
More often than not, hardness and toughness go hand-in-hand. A steel that is high-hardness usually means that its toughness is low, but this isn’t true of M2 steel. M2 steel’s toughness is adequate, which makes for a good-quality and resilient knife. When the toughness of the steel is high, this means that your M2 knife won’t break easily if it is used to cut or work with harder substances.
M2 Edge Retention
M2 Steel has some of the best edge retention that is possible in a knife. Due to the high carbon amounts, a knife made out of M2 steel will have to be sharpened very rarely. The steel is so hard that there are very few dulling substances that the blade can come in contact with. While your kitchen knife made from M2 steel will likely damage a wooden cutting board, you won’t have to deal with sharpening your knife every time you use it.
M2 Ease of Sharpening
Even though it would be convenient, M2 steel cannot be easily sharpened and have high edge retention and at the same time. Since an M2 steel knife consists of high-carbon steel with high hardness, it is harder to sharpen a knife made of M2 steel.
Thankfully, M2 steel knives remain sharp for a long time, which means that you don’t have to worry about needing to sharpen them quite often.
M2 Corrosion Resistance
M2 has a low-to-moderate amount of Chromium content. At 4.15% of Chromium, a knife made out of M2 will be corrosion resistant but may not be completely immune to it.
We definitely recommend that you take care of your M2 knife and ensure that it stays clean and dry in order to avoid any formation of rust or corrosion. You will also benefit from oiling your knife every once in a while, particularly if you live in a humid area.
Is M2 Good for Knives?
M2 is a great steel for Knives.
Its hardness does not mean that you sacrifice its toughness, and it also has wonderful edge retention properties, which means that this steel is ideal for making knives. Having said that, M2 works best for certain types of knives when compared to others. For example, it does not work well in the kitchen, if you want to use it as a paring knife. However, M2 knives work well outdoors, if it’s part of a survival kit or wilderness kit, for instance.
You must take care of the M2 knife, because of its low corrosion resistance. It is also difficult to sharpen. However, its overall performance is definitely worth it.
Is M2 a Stainless Steel?
Yes, M2 is a stainless steel due to the decent chromium content. You must take care of an M2 knife to ensure that it doesn’t rust or corrode, and also oil it once in a while to eliminate moisture content.
How Does M2 Compare to Other Steels?
M2 is a great knife if hardness, toughness, and edge retention matter to you. However, to make sure that its the best steel for the type of knife you’re thinking, you need to examine other types of steel.
We’ve put together a table of three steels more similar to M2. We’ll look at the prices and properties of these other steels to help you make a decision about which steel type performs best.
M2 Steel vs. 440C Steel
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The most noticeable difference between the 440C and the M2 Steel is the resistance to corrosion. Since 440C is stainless steel, it can offer much better corrosion resistance. However, M2 is harder, tougher, and has better edge retention.
M2 Steel vs. S30v
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Both types of steel are high-carbon high-alloys offering good toughness. However, the M2 has better edge retention. The S30V has better corrosion resistance than the M2. It’s also easier to sharpen the S30V.
M2 vs. Maxamet Steel
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M2 Steel is still considered a stainless steel while Maxamet steel is a high-carbon steel. Of course, M2 is better than Maxamet steel in terms of toughness and edge retention.
M2 is a great option for someone looking for a fuss-free stainless steel knife. You get great features in hardness, toughness, edge retention, and wear resistance. The corrosion resistance of M2 is enough for it to be stainless steel, but we still recommend that you take care of it.
Let us know about your experiences with the M2 knife! We hope you were able to make your decision after reading this ultimate guide to M2 steel. Good luck.