Main Types of High Speed Steel
High speed steel is a complex type of steel, with a carbon content generally between 0.70 and 1.65%. It contains a large amount of alloy elements, with a total amount of 10-25%.
It can be divided into:
① Tungsten series high speed steel (containing 9 to 18% tungsten);
② Tungsten molybdenum high speed steel (containing 5-12% tungsten and 2-6% molybdenum);
③ High molybdenum high speed steel (containing 0 to 2% tungsten and 5 to 10% molybdenum);
④ Vanadium high-speed steel can be divided into high-speed steel with general vanadium content (1-2% vanadium content) and high vanadium content (2.5% vanadium content) according to the different vanadium content;
⑤ Cobalt high-speed steel (containing 5-10% cobalt).
According to different uses, high-speed steel can be divided into two types: general purpose steel and special purpose steel.
① General purpose high-speed steel: mainly used for manufacturing cutting tools (such as drills, taps, and saw blades) and precision tools (such as hobs, gear shapers, and broaches) for cutting metal materials with a hardness of HB ≤ 300. Common steel grades include W18Cr4V, W6Mo5Cr4V2, and so on.
② Special purpose high-speed steel: including cobalt high-speed steel and superhard high-speed steel (hardness HRC68-70), mainly used for manufacturing tools for cutting difficult to process metals (such as high-temperature alloys, titanium alloys, and high-strength steels). Common steel grades include W12Cr4V5Co5, W2Mo9Cr4VCo8, and so on.
General purpose steel
Steel grade: W18Cr4V (W18)
Hardness HRC: 62-65
Bending strength/GPa: 3.0-3.4
Impact toughness/(MJm ²）： 0.18-0.32
Hardness at 600 ℃ HRC: 48.5
Features: Good strength, good grindability, suitable for grinding with ordinary steel abrasive wheels, medium heat resistance, and poor thermoplasticity
Main Uses: Strong versatility, widely used in the manufacture of drills, reamers, taps, milling cutters, gear cutters, broaches, etc.
High performance steel
Steel grade: W6Mo5Cr4V2 (M2)
Hardness HRC: 63-66
Bending strength/GPa: 3.5-4.0
Impact toughness/(MJm ²）： 0.30-0.40
Hardness at 600 ℃ HRC: 47-48
Features: High strength, good thermoplasticity, slightly inferior to W18Cr4V in heat resistance and grindability, suitable for grinding with ordinary steel jade grinding wheels
Main use: Suitable for making hot forming tools and tools that withstand impact and have weak structures
Steel grade: W14Cr4VMnRE
Hardness HRC: 64-66
Bending strength/GPa: about 4.0
Impact toughness/(MJm ²）： About 0.31
Hardness at 600 ℃ HRC: 50.5
Main use: The cutting performance is equivalent to W18Cr4V, suitable for making hot rolling tools.