Hardness Conversion Calculator
Convert between common hardness scales used in metallurgy and materials engineering. Enter a hardness value in one scale and get approximate equivalents in Rockwell C, Rockwell B, Brinell, Vickers, and tensile strength for steel.
Material hardness is measured with several different scales, and engineers often need to convert between them. Each scale uses a different test method (indenter shape, applied force), so conversions are approximate and depend on the material.
Common Hardness Scales:
| Scale | Method | Typical Use |
|---|---|---|
| Rockwell C (HRC) | Diamond cone, 150 kgf | Hardened steel (20-70 HRC) |
| Rockwell B (HRB) | 1/16" ball, 100 kgf | Softer steel, brass (60-100 HRB) |
| Brinell (HB) | 10mm ball, 3000 kgf | Castings, forgings |
| Vickers (HV) | Diamond pyramid | All materials, any hardness range |
Example Conversions (Steel):
| HRC | HB | HV | Tensile (ksi) |
|---|---|---|---|
| 20 | 516 | 562 | 278 |
| 30 | 689 | 746 | 351 |
| 40 | 862 | 930 | 424 |
| 50 | 1035 | 1114 | 497 |
| 60 | 1208 | 1298 | 570 |
Important: These conversions are approximations based on ASTM E140 standard tables for carbon and alloy steels. Non-ferrous metals, stainless steels, and other alloys may have different conversion relationships. Always use material-specific data for critical applications.