China · GB
SM55
GB/T 1299:2014 — Tool and mould steels
Chemical composition
| Element | min | max | Similar | Remarks |
|---|---|---|---|---|
| C | 0.52 | 0.58 | ||
| Cr | 0.25 | |||
| Cu | 0.25 | |||
| Mn | 0.5 | 0.8 | ||
| Ni | 0.25 | |||
| P | 0.025 | |||
| S | 0.025 | |||
| Si | 0.17 | 0.37 |
Mechanical properties
| Heat treatment / condition | Yield strength | Tensile strength | Elongation | Reduction of area | Impact energy | Hardness |
|---|---|---|---|---|---|---|
| steel products, hot rolled | HB 170–230；HR 170–230 |