24 July 2021 High Speed Steel Bar
PM-M4 High Speed Steel Bar
PM-M4 steel has higher hardness, red hardness, wear resistance and toughness. Suitable for high-performance IC molds for long-life cold plastic processing; suitable for tools that require high wear resistance and high toughness, such as long-life taps, broaches, single-tooth thin-edged tools, etc. High-carbon, high-vanadium PM-M4 powder high-speed steel, the steel contains a lot of elements such as W, Mo, Cr, V, and the alloy carbide formed with carbon improves the performance of the steel. Due to the uniqueness of powder high-speed steel smelting, the content of alloying elements is higher, especially the application of high-V and high-Co steels is more common.
The effects of W and Mo in high-speed steel are similar. The alloy carbide formed by carbon is strengthened by dissolution and precipitation, so that high-speed steel has a special secondary hardening effect, and the red hardness is greatly improved; V in steel is a strong carbide forming element. VC is finely dispersed and improves the wear resistance of steel. With the increase of V content, the flexural wear resistance of high-speed steel is greatly improved; Co is one of the strongest solid solution strengthening alloy elements, which is improved by solid solution matrix strengthening The hardness and hot hardness of high-speed steel greatly increase the tool life.
Chemical Composition:
| C(％) | Si(％) | Mn(％) | P(％) | S(％) | Cr(％) | W(％) | Mo(％) | Co(％) | N(%) | O(%) | Ar(%) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1.25～1.40 | 0.20 ~ 0.45 | 0.15 ~ 0.40 | ≤0.030 | ≤0.030 | 3.75～4.75 | 5.25 ~ 6.50 | 4.25 ~ 5.50 | ≤0.50 | ≤0.08 | ≤0.015 | ≤0.05ppm |
Mechanical Propoerties:
| Yield Strength Rp0.2(MPa) | Tensile Strength Rm(MPa) | Impact Energy KV(J) | Elongation at Fracture A(%) | Impact toughness value αkv (J/cm2) | Hardness |
|---|---|---|---|---|---|
| ≥ 1920(100) | ≥ 2080(110) | ≥ 98 | ≥ 9 | ≥ 90 | ≥ 61 HRC |
PM-M4 High Speed Steel Heat Treating:
| Annealing | Preheat | Austenitizing | Quench | Tempering |
|---|---|---|---|---|
| Temp | Temp | Temp | Medium | Temp |
| °F | °F | °F | °F | |
| 1550/1600 | 1500/1550 | 2175/2220 | Salt/Oil/Atm | 1025/1050 |