High speed steel is a kind of complex steel with carbon content between 0.70% and 1.65%. The total content of alloying elements is 10-25%. According to the different alloy elements, it can be divided into: ① tungsten high speed steel (containing 9-18% of tungsten); ② tungsten molybdenum high speed steel (containing 5-12% of tungsten and 2-6% of molybdenum); ③ high molybdenum high speed steel (containing 0-2% of tungsten and 5-10% of molybdenum); ④ vanadium high speed steel, according to the different vanadium content, it can be divided into general vanadium content (containing 1-2% of vanadium) and high vanadium content (containing 2.5-5%) high speed steel; ⑤ cobalt high speed steel (containing 5-10% of cobalt) ) According to different uses, high speed steel can be divided into two types: general purpose and special purpose. ① Universal high speed steel: it is mainly used for manufacturing cutting tools (such as drill, tap, saw blade) and precision tools (such as hob, gear shaper, broach) for metal materials with hardness HB ≤ 300. The commonly used steel grades are W18Cr4V, W6Mo5Cr4V2, etc. ② Special purpose high speed steel: including cobalt high speed steel and superhard high speed steel (hardness hrc68-70), which are mainly used to manufacture cutting tools for difficult to machine metals (such as high temperature alloy, titanium alloy and high strength steel, etc.), and commonly used steel grades are w12cr4v5co5, w2mo9cr4vco8, etc.

General steel

Steel grade: W18Cr4V (w18)

Hardness HRC: 62-65

Bending strength / GPA: 3.0-3.4

Impact toughness / (MjM & sup2;): 0.18-0.32

Hardness at 600 ℃ HRC: 48.5

Features: good strength, grindability, grindability with common emery wheel, moderate heat resistance, poor thermoplasticity

Main uses: universal, widely used in the manufacture of drill, reamer, tap, milling cutter, gear cutter and broach.

High performance steel

Steel grade: W6Mo5Cr4V2 (M2)

Hardness HRC: 63-66

Bending strength / GPA: 3.5-4.0

Impact toughness / (MjM & sup2;): 0.30-0.40

Hardness at 600 ℃ HRC: 47-48

Features: high strength, good thermoplasticity, slightly lower heat resistance and grindability than W18Cr4V, which can be grinded with ordinary emery wheel

Main use: suitable for making hot forming tools and tools with weak structure and impact

Steel grade: w14cr4vmnre

Hardness HRC: 64-66

Bending strength / GPA: about 4.0

Impact toughness / (MjM & sup2;): About 0.31

Hardness at 600 ℃ HRC: 50.5

Main use: the cutting performance is equivalent to W18Cr4V, suitable for making hot rolling tools.