ASTM A453 Grade 660 Mechanical Properties
| Tensile Class | Tensile Strength, min | Yield strength, min, (0.2% offset) | Elongation in 4D, min, % | Reduction of Area, min, % | ||
| ksi | Mpa | ksi | Mpa | |||
| A, B and C | 130 | 895 | 85 | 585 | 15 | 18 |
| D | 130 | 895 | 105 | 725 | 15 | 18 |
ASTM A453 Grade 660 Hardness
| Tensile Class | Brinell Hardness Number | Approximate Rockwell Hardness B & C | |
| min | max | ||
| A, B and C | 248 - 341 | 24 HRC | 27 HRC |
| D | 248 - 321 | 24 HRC | 35 HRC |
ASTM A453 Grade 660 Stress Rupture Requirements
| Tensile Class | Test Temperature ºF [ºC] | Stress, min | Time to Rupture, min, h [Note] | Elongation, min, % | |
| ksi | Mpa | ||||
| A, B and C | 1200 [650] | 56 | 385 | 100 | 5 |
| D | 1200 [650] | 40 | 275 | 100 | 5 |
Note : The combination bar specimen shall be tested continuously at the temperature and at the minimum stress specified or at a greater stress and shall rupture in a time not less than that specified.