硬度标尺 | 标准块的硬度范围 | 示值zei大允许误差 | 离散性误差 |
HRA | (20~75)HRA (>75~88)HRA | ±2HRA ±1.5HRA | ±0.2 ±0.2 |
HRB | (20~45)HRB (>45~80)HRB (>80~100)HRB | ±4HRB ±3HRB ±2HRB | ±0.2 ±0.2 ±0.2 |
HRC | (20~70)HRC | ±1.5HRC | ±0.2 |