Japan's Hitachi SKH9 special high-quality high-speed tool steel
Relatively standard and features: M2 chemical analysis results (%):
0.8 - 0.9 Carbon Silicon: 0.45 The following chromium :3.8-4 .5 Mn: 0.45 The following Mo 4.5-5.5 V :1.6-2.2 W :5.5-6.7 P: 0.03 S: 0.01
Steel properties: high-speed steel
Steel general purpose: cutting wear is appropriate manufacturing strength, high modulus Heng, screw mode, the more complex needs toughness and shape tools, milling cutters, drills and other factory condition and hardness (surface): HB900-1100/HRC63
SKH9 forging technology and features:
Forging: 1.100 ~ 900 ℃
Annealing: Heat to 800-850 ℃, remain at this temperature in two to four hours in the furnace allowed to cool gradually.
Quenching: the first pre-heated to 550-600 ℃, times heated to 950 ℃, and then heated to a: 1,220 ~ 1250 ℃; b: 1,200 ℃ ~ 1230 ℃. Hardened in oil,
But the oil temperature must be moisture 40-60 ℃ (a. general tools; b. form a complex type of tool needed toughness)
Tempering: heating to 550-570 ℃, to stay at this temperature and then cooled in still air, tempering must be repeated twice
Hardness: HRC63 ℃ above.
Use: This high-speed steel, tungsten steel, appropriate for manufacturing powerful cutting wear resistance, impact tools, high-level die, screw mold and shape the more complex tools to be resilient, cutters, drills, etc.
