CARBON TOOL STEELS SK GRADE
| MATERIALS GRADE |
CHEMICAL COMPOSITION % | ||||
| C | Si | Mn | P | S | |
| SK140 (SK1) |
1.30～1.50 | 0.10～0.35 | 0.10～0.50 | 0.030 max. | 0.030 max. |
| SK120 (SK2) (TC120) |
1.15～1.25 | 0.10～0.35 | 0.10～0.50 | 0.030 max. | 0.030 max. |
| SK105 (SK3) (TC105) |
1.00～1.10 | 0.10～0.35 | 0.10～0.50 | 0.030 max. | 0.030 max. |
| SK95 (SK4) |
0.90～1.00 | 0.10～0.35 | 0.10～0.50 | 0.030 max. | 0.030 max. |
| SK90 (TC90) |
0.85～0.95 | 0.10～0.35 | 0.10～0.50 | 0.030 max. | 0.030 max. |
| SK85 (SK5) |
0.80～0.90 | 0.10～0.35 | 0.10～0.50 | 0.030 max. | 0.030 max. |
| SK80 (TC80) |
0.75～0.85 | 0.10～0.35 | 0.10～0.50 | 0.030 max. | 0.030 max. |
| SK75 (SK6) |
0.70～0.80 | 0.10～0.35 | 0.10～0.50 | 0.030 max. | 0.030 max. |
| SK70 (TC70) |
0.65～0.75 | 0.10～0.35 | 0.10～0.50 | 0.030 max. | 0.030 max. |
| SK65 (SK7) |
0.60～0.70 | 0.10～0.35 | 0.10～0.50 | 0.030 max. | 0.030 max. |
| SK60 | 0.55～0.65 | 0.10～0.35 | 0.10～0.50 | 0.030 max. | 0.030 max. |
HEAT TREATMENT
| MATERIALS GRADE |
HEAT TREATMENT ℃ | |
| QUENCH | TEMPER | |
|
SK140 SK120 SK105 SK95 SK90 SK85 SK80 SK75 SK70 SK65 SK60 |
750～810 Water quench 750～810 Water quench 750～810 Water quench 750～810 Water quench 750～810 Water quench 750～810 Water quench 760～820 Water quench 760～820 Water quench 770～830 Water quench 770～830 Water quench 780～840 Water quench |
150～200 Air cooled 150～200 Air cooled 150～200 Air cooled 150～200 Air cooled 150～200 Air cooled 150～200 Air cooled 150～200 Air cooled 150～200 Air cooled 150～200 Air cooled 150～200 Air cooled 150～200 Air cooled |