Conversion of hardness-to-hardness or hardness-to-tensile-strength values for unalloyed and low-alloy steels and cast iron.

Based on ISO 18265-2003

Bossard calculators and converters are designed for engineers, technicians, designers and students involved in the development and assembly of bolted joints. 


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Valid range
Tensile strength Login required N/mm² 255 - 2180
Vickers hardness Login required HV10 80 - 940
Brinell hardness Login required HB 76 - 618
Rockwell hardness Login required HRB 41 - 105
Rockwell hardness Login required HRF 82.6 - 115.1
Rockwell hardness Login required HRC 20.3 - 68
Rockwell hardness Login required HRA 60.7 - 85.6
Rockwell hardness Login required HRD 40.3 - 76.9
Rockwell hardness Login required HR15N 69.6 - 93.2
Rockwell hardness Login required HR30N 41.7 - 84.4
Rockwell hardness Login required HR45N 19.9 - 75.4

This application is based on ISO 18265-2003:
Metallic materials, conversion of hardness values.

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