France · AFNOR NF
42 CD 4
NF A35-557
Chemical composition
| Element | min | max | Similar | Remarks |
|---|---|---|---|---|
| C | 0.39 | 0.45 | ||
| Cr | 0.9 | 1.2 | ||
| Mn | 0.6 | 0.9 | ||
| Mo | 0.15 | 0.25 | ||
| P | 0.035 | |||
| S | 0.035 | |||
| Si | 0.1 | 0.4 |
Mechanical properties
| Heat treatment / condition | Yield strength | Tensile strength | Elongation | Reduction of area | Impact energy | Hardness |
|---|---|---|---|---|---|---|
| bars, fasteners, wire rod, quenched and tempered | 950 | 1180 1380.00 | 8 | 30 |
Heat treatment
| Type | 1 |
|---|---|
| Heat-treatment curve | CCT modified |
| Heat-treatment curve | Hardness-Tempering |
| Heat-treatment curve | CCT |
| Heat-treatment curve | TTT |
| Heat-treatment curve | 淬透性 |