eFunda: Convert Hardness: Tensile Strength (Approx.)
 Convert Hardness
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 Tensile Strength (Approximation)
Symbol:  Approx. TS

An approximate relationship between the hardness and the tensile strength (of steel) is,

where HB is the Brinnell Hardness of the material, as measured with a standard indenter and a 3000 kgf load.

 Convert   Approx. TS     MPa   (suggested range: 390 ~ 2450 MPa)
 Approx. TS   1420   MPa   approximately* = Hardness Symbol Amount Name SuggestedRange HB (3000) 408 Brinell 10 mm Standard 3000 kgf 80~445 HB (500) >> Brinell 10 mm Standard 500 kgf 89~189 HB (Tungsten 3000) 408 Brinell 10 mm Tungsten 3000 kgf 80~620 HB (Indentation) 3.04 mm Brinell Indentation 6~2 HK 452 Knoop 97~920 HM 4 Mohs 1~10 HRA 72 Rockwell A-Scale 59~86 HRB >> Rockwell B-Scale 41~100 HRC 44 Rockwell C-Scale 19~69 HRD 58 Rockwell D-Scale 39~77 HRF >> Rockwell F-Scale 88~100 HR-15N 82 Rockwell Superficial 15N 69~94 HR-15T >> Rockwell Superficial 15T 77~93 HR-30N 63 Rockwell Superficial 30N 41~85 HR-30T >> Rockwell Superficial 30T 53~82 HR-45N 48 Rockwell Superficial 45N 19~76 HR-45T >> Rockwell Superficial 45T 28~71 HS 58 Shore Scleroscope 17~97 HV 432 Vickers 20~1800

 Legend << The hardness value is below the acceptable range of the particular hardness scale. >> The hardness value is above the acceptable range of the particular hardness scale. ### The hardness value is near the limit (within 15%) of the acceptable range of the particular hardness scale. * The many hardness tests listed here measure hardness under different experimental conditions (e.g. indenters made in different sizes, shapes, and materials, and applied with different loads) and reduce their data using different formulae. As a result, there is NO direct analytic conversion between hardness measures. Instead, one must correlate test results across the multiple hardness tests. This calculator is based on hardness data compiled from ASM Metals Reference Book 3rd ed, published by ASM International, and Machinery's Handbook 25th ed, published by Industrial Press. The calculator curve-fits multiple hardness data onto a common polynomial basis and then performs an analytic conversion. The accuracy of the conversion depends on the accuracy of the provided data and the resulting curve-fits, and on the valid ranges spanned by the different hardness tests. Converted hardness values should be used for comparative purposes only.