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Steel Characteristics Table 2
| Grade | Fracture Grain Size Hardened | Impact Strength | Hardness Working Rockwell | Hardness Quenched Rockwell | Hardness Annealed Brinell | Decarb Susceptability |
|---|---|---|---|---|---|---|
| A-10 | Medium | Low | ||||
| A-2 | 8.5 | Medium | 58-62 | 63-65 | 202-248 | Low |
| A-6 | 9 | Medium | 58-62 | 61-63 | 217-248 | Low |
| D-2 | 8.5 | Low | 58-62 | 63-65 | 212-255 | Low |
| D-7 | 8.5 | Low | 58-65 | 65-67 | 217-262 | Medium |
| H-13 | 7.5 | High | 45-53 | 52-55 | 202-235 | Low |
| M-2 | 9.5 | Medium | 64-66** | 63-65 | 202-248 | Low |
| M-4 | 9.5 | Low | 62-66** | 67-68 | 212-255 | Medium |
| M-42 | 9 | Low | 66-68 | 65-68 | 229-269 | Medium |
| O-1 | 9 | Low | 58-62 | 64-65 | 179-212 | Low |
| O-6 | 9 | Low | 58-62 | 63-64 | 179-229 | Medium |
| S-1 | 7.5 | High | 53-58 | 56-58 | 179-229 | Low |
| S-5 | 9 | High | 52-60 | 60-62 | 202-229 | Medium |
| S-7 | 9 | High | 52-58 | 60-62 | 180-229 | Medium |
| T-1 | 9.5 | Low | 63-65 | 64-65 | 202-248 | Low |
| T-15 | 9.5 | Low | 66-68 | 65-68 | 241-277 | Medium |
| VERTEX | Medium | 58-62 | 64-65 | 212-248 | Low | |
| W-1 | High | 58-65 | 65-67 | 156-202 | Low |
*Fracture grain size numbers refer to Shephard fracture standards.
**Can be underhardened and used at RC 58/62 for cold work applications