Convert Hardness to Tensile Strength

The following sections contain JavaScript routines to convert hardness values to tensile strengths. If you don't have JavaScript turned on in your browser, the forms for entering values will show up, but the conversions won't be performed. (You can, however, see the underlying formulas by viewing the HTML source for this document. Even if you haven't programmed in JavaScript the conversion formulas are fairly easy to read.)

The conversions are performed with polynomials that were fit to the data presented in the American Society for Metals' Metals Handbook Desk Reference. The values you'll get here are generally within 1 ksi of the handbook values, which should be good enough for most purposes. The conversions are intended for carbon and alloy steels in the annealed, normalized, and quenched-and-tempered conditions.

Note: 1 ksi = 1,000 psi.

Rockwell B Hardness to Tensile Strength

Rockwell C Hardness to Tensile Strength

Brinell (3000 kg) Hardness to Tensile Strength

If you're familiar with hardness testing, you realize that although the strength values are given to the nearest ksi, the conversions aren't as accurate as that. If you're not familiar with hardness testing, you should get familiar before you try to use conversions like this. Some good references to learn about hardness testing--apart from the text mentioned above--are:

Volume 8 of ASM's Metals Handbook

Lysaght & DeBellis's Hardness Testing Handbook