What are the main categories of high speed steel?

High-speed steel is a complex steel, the carbon content is generally between 0.70 and 1.65%. The amount of alloying elements is large, and the total amount can reach 10 ~ 25%.

According to the alloy elements contained can be divided into:

① Tungsten high-speed steel (including tungsten 9 ~ 18%);

② Tungsten-molybdenum high-speed steel (containing tungsten 5 ~ 12%, containing molybdenum 2 ~ 6%);

③ High molybdenum high-speed steel (containing tungsten 0 ~ 2%, containing molybdenum 5 ~ 10%);

(4) Vanadium high speed steel, according to the amount of vanadium content is divided into general vanadium content (vanadium content 1 ~ 2%) and high vanadium content (vanadium content 2.5 ~ 5%) of high speed steel;

⑤ Cobalt high-speed steel (containing cobalt 5 ~ 10%).

According to different uses of high-speed steel can be divided into general and special purpose two.

① Universal high-speed steel: mainly used for manufacturing cutting tools (such as drills, taps, saw blades) and precision tools (such as hobs, gear shaper knives, broach) of metal materials with cutting hardness HB≤300, commonly used steel numbers are W18Cr4V, W6Mo5Cr4V2 and so on.

② Special purpose high-speed steel: including cobalt high-speed steel and super-hard high-speed steel (hardness HRC68 ~ 70), mainly used for manufacturing cutting difficult metal (such as superalloy, titanium alloy and high-strength steel, etc.) tools, commonly used steel numbers W12Cr4V5Co5, W2Mo9Cr4VCo8 and so on.

General-purpose steel

Steel number: W18Cr4V(W18)

Hardness HRC: 62-65

Flexural strength /GPa: 3.0-3.4

Impact toughness/(MJm²) : 0.18-0.32

Hardness HRC at 600℃ : 48.5

Features: Good strength, good grindability, can be ground with ordinary steel jade grinding wheel, medium heat resistance, poor thermoplasticity

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

High performance steel

Steel number: W6Mo5Cr4V2(M2)

Hardness HRC: 63-66

Bending strength /GPa: 3.5-4.0

Impact toughness/(MJm²) : 0.30-0.40

Hardness HRC at 600℃ : 47-48

Features: high strength, good thermoplasticity, heat resistance, grindability slightly lower than W18Cr4V, can be grinding with ordinary steel jade wheel

Main applications: Suitable for making hot forming tools and tools with weak structure and impact resistance

Steel number: W14Cr4VMnRE

Hardness HRC: 64-66

Bending strength /GPa: approx. 4.0

Impact toughness/(MJm²) : approximately 0.31

Hardness HRC at 600℃ : 50.5

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