24 July 2021 High Speed Steel Bar
SKH57 High Speed Steel Bar
SKH57 is a kind of high-speed tool steel, which is a grade of Japanese JIS standard. SKH57 high-speed steel has the characteristics of wear resistance and sintering resistance. It is mostly used for cold forging dies, drawing dies, cutting tools, etc., and its soft annealing hardness is ≤285HB. This steel can still maintain high hardness at a working temperature of about 600°C. High temperature hardness is a very important performance for hot-deformed molds and high-speed cutting tool steels. SKH57 has good wear resistance, under the condition of considerable pressure and friction, the tool can still keep its shape and size unchanged. It has certain high-temperature mechanical properties, thermal fatigue, thermal conductivity and corrosion resistance. Equivalent to DIN 1.3207 and China GB Standard W10Mo4Cr4V3Co10 .
Chemical Composition:
| C(％) | Si(％) | Mn(％) | P(％) | S(％) | Cr(％) | V(％) | W(％) | Mo(％) | Co(%) | Cu(%) |
|---|---|---|---|---|---|---|---|---|---|---|
| 1.20～1.35 | ≤0.45 | ≤0.40 | ≤0.030 | ≤0.030 | 3.80～4.50 | 3.00 ~ 3.50 | 9.00 ~ 10.00 | 3.20～3.90 | 9.50 ~ 10.50 | ≤0.25 |
Mechanical Propoerties:
| Yield Strength Rp0.2(MPa) | Tensile Strength Rm(MPa) | Impact Energy KV(J) | Elongation at Fracture A(%) | Reduction in Cross Section on Fracture Z(%) | Impact toughness value αkv (J/cm2) | Hardness |
|---|---|---|---|---|---|---|
| ≥ 1880(80) | ≥ 1990(100) | ≥ 98 | ≥ 9 | ≥ 60 | ≥ 80(6) | ≥ 64 HRC |
Hardness:
Delivery hardness: (other processing methods) ≤ 269HB; (annealing) ≤ 255HB. Sample heat treatment system and quenching and tempering hardness: ≥64HRC
Application:
High speed steel is generally widely used in the field of machining at high speeds. With the excellent abrasion resistance, high temperature properties and excellent hardness, high speed steels (HSS) have become material a wide range of applications including cutting tools, such as drills, taps, milling cutters, tool bits, gear cutters, saw blades and rolls, such as hot strip mill finishing train, rod and bar mill finishing, universal mill finishing. High speed steels also found a market in fine hand tools where their relatively fine toughness at high hardness, coupled with high abrasion resistance, made them suitable for low speed applications requiring a durable edge, such as chisels, hand plane, blades, and high quality kitchen hardware, pocket knives, swords.
Heat treatment specification and metallographic organization：
Heat treatment specifications: quenching, 730 ~ 840 ° C preheating, 1190 ~ 1210 ° C (salt bath furnace) or 1200 ~ 1220 ° C (box furnace) heating, oil cooling, 540 ~ 560 ° C tempering 2 times, each time 2h.