Several esteemed knife makers such as Benchmade and Gerber had used M2 steel for their knives. But you hardly find knives with M2 blades these days.
Nevertheless, M2 is used in several industrial tasks, including those of making knives. This is attributed to its desirable properties. So, should you choose it for your next knife? Read on before you decide…
What is M2 Steel?
AISI M2 belongs to the category of tool steels. It is a part of the tungsten-and-molybdenum series, due to its high tungsten and molybdenum content. It is also high-speed steel, as it can endure high temperatures without compromising its hardness.
This medium-alloyed steel comes with a good mix of well-balanced toughness, red hardness, machinability, and wear resistance properties. It has replaced high-speed T1 steel in most applications due to its relative affordability and better performance.
Any high-speed steel is primarily used in making a variety of cutting tools. Thus, M2 is also used for manufacturing tools such as knives, saws, taps, reamers, twist drills, and milling cutters. It is also in cold work punches, dies, plastic molds with raised wear resistance, and applications demanding high speed and light cuts. Due to the ability to sustain its temper at very high temperatures, M2 is ideal for high-heat cutting jobs.
In the world of knives, it is used to manufacture upscale limited-edition knives and custom knives. It is worth knowing that the popularity of M2 had dropped around 2005. M4 replaced it, which is also high-speed tool steel with better toughness, hardness, and edge holding properties.
M2 has minimal chromium content and is not stainless. Following are the different elements of this tool steel:
- 0.85% Carbon: For improved tensile strength, hardness, and resistance
- 4.15% Chromium: For improved tensile strength, hardness, toughness, and resistance to corrosion
- 6.15% Tungsten: For improved hardenability, hardness at high temperatures, strength, and toughness
- 5.00% Molybdenum: For improved strength, toughness, and hardness
- 1.85% Vanadium: For improved toughness, strength, and resistance to wear
- 0.45% Silicon: For improved strength
- 0.30% Nickel: For improved toughness
- 0.280% Manganese: For improved hardenability and resistance to wear
- 0.25% Copper: For better resistance to corrosion by preventing surface oxidization
- 0.030% Phosphorus: For improved strength, hardness, and machinability
- 0.030% Sulfur: For more machinability
On the Rockwell scale, the hardness rating of M2 high-speed steel ranges from 62 to 65 HRC. However, the exact value shall vary according to the given heat treatment. This hardness range is considered high. The credit goes to the ideal mix of carbon, molybdenum, and manganese.
- Reliable Toughness: Considering the high hardness level of M2, it is clear that it is less tough, isn’t it? After all, it is a rule that the harder the steel is, the less tough it is! However, M2 has proven to be an exception here. M2 is used as a classic option when it comes to making straight knives for jointers and planers. This itself gives an insight into how tough M2 is, as these knives are expected to endure shock loads. This is possible only if their build material is highly tough. Ideally, tempering M2 results in good toughness as well as edge holding ability. M2 steel knives can easily endure batoning impact, droppings, and even flexing without triggering any symptoms of cracking or breaking.
- High Wear Resistance: If a steel material is hard, it is certainly going to be resistant to wear. This is because the higher the hardness, the more is this resistance power. The composition of M2 facilitates the formation of evenly distributed, small carbides that provide high wear resistance. The credit also goes to the high levels of tungsten and molybdenum, especially tungsten that is hard to find in steels. This tool steel is known to ensure good wear resistance even when it becomes highly hot.
- Great Edge Retention: Another commendable property of M2 that makes it an ideal option for knives is its ability to retain a sharp edge for long. This is what any knowledgeable knife user would expect from steels made for making high-speed cutting tools. Surprisingly, M2 can hold a sharp edge better than a few high-end steel options. The higher the power to resist wear and tear, the better is the edge retention quality.
- Okay Corrosion Resistance: As the amount of chromium is just 4.15%, M2 is not stainless. Thus, you cannot expect it to perform well when it comes to resisting rust and corrosion. Still, it provides a fair level of corrosion resistance.
- Ease of Sharpening: As M2 is hard, it is not the easiest one to sharpen. It is also not the most difficult one to sharpen, too. When it comes to sharpening, the challenge comes from its property of high resistance to wear or abrasion.
Comparison With Other Knife Steel Options
M2 vs D2
D2 and M2 are considered quite close. When treated to the same level of hardness, M2 is tougher and provides improved resistance to wear. It also wins over D2 when it comes to edge retention. However, D2 wins in terms of corrosion resistance. D2 is harder to sharpen as well.
M2 vs M4
Both are tool steels. M4 is the upgraded version of M2 and is known to be tougher at the same level of hardness. As M4 has more carbide volume, it is more resistant to wear, holds an edge better, and is less challenging to grind than M2, given that the hardness level is the same. However, both steels have not-so-great anti-corrosion qualities.
So, is M2 Steel Good?
It is truly a good option for knives, as it can retain a sharp edge well for long, resist wear extremely well, and keep cracking or breaking at bay. Just ensure that you do not carry an M2 steel knife in a humid and salty environment.
Hi, I am Jay. I am the creator of Knife Guides, your one-stop site for everything related to knives. I am a computer engineer by profession, knife aficionado by passion. Here I work with a group of people who’ve always had a passion for knives and blades. Over the years we’ve kind of become experts and decided to share our knowledge and ideas. I am also an avid hiker and enjoy offshore gamefishing.