Hrb hrc conversion table

Equivalents approx. (maximum value) in imperial and metric units.

Hardness is the property of a material that enables it to resist plastic deformation, penetration, indentation, and scratching. Therefore, hardness is important from an engineering standpoint because resistance to wear by either friction or erosion by steam, oil, and water generally increases with hardness.

Several methods have been developed for hardness testing. Those most often used are Brinell, Rockwell, Vickers, Tukon, Sclerscope, and the files test. The first four are based on indentation tests and the fifth on the rebound height of a diamond-tipped metallic hammer. The file test establishes the characteristics of how well a file takes a bite on the material.

As a result of many tests, comparisons have been prepared using formulas, tables, and graphs that show the relationships between the results of various hardness tests of specific alloys. There is, however, no exact mathematical relation between any two of the methods. For this reason, the result of one type of hardness test converted to readings of another type should carry the notation "____ converted from ____" (for example "352 Brinell converted from Rockwell C-38").

Another convenient conversion is that of Brinell hardness to ultimate tensile strength. For quenched and tempered steel, the tensile strength (psi) is about 500 times the Brinell hardness number (provided the strength is not over 200,000 psi).

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Hrb hrc conversion table

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Glossary Terms and Definitions

Related to Hardness

Find numerical entries by alphabetical spelling.

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An Abbreviation for Brinell Hardness Number. Now abbreviated HBW.

Now abbreviated HBW. A designation of hardness, usually of steel, performed by pressing a 10 mm spherical tungsten carbide ball against a clean prepared surface using a 3000 Kilogram force, producing an impression, measured and given a special numerical value. This numerical value relates to steel tensile strength. API Spec 6A specifies minimum Brinell Hardness requirements for different material designations. NACE Standard MR0175 references maximum hardness in determining steel’s suitability for use in H2S Service.

A measured factor that reasonably predicts the amount metal will resist abrasion and bending, as well as indicating Ultimate Strength. Most commonly expressed as Brinell Hardness and Rockwell Hardness. ASTM E140 provides a guide for comparing hardness determined by different methods and expressed on different scales.

Abbreviation for Brinell Hardness, taken using a carbide ball indenter.

(Sometimes RB ) An abbreviation for Rockwell Hardness measured on the B scale. The abbreviation usually appears after a number, e.g. 83 HRB. See: Rockwell B Hardness .

(Sometimes RC ) An abbreviation for Rockwell Hardness measured on the C scale. The abbreviation usually appears after a number, e.g. 22 HRC. See: Rockwell C Hardness .

Abbreviation for Hardness Vickers. The Vickers hardness testing method represents another method of testing by indenting the test material under a specified load and measuring the size of the indention and comparing it to a number table. This method has gained greater use in testing of weld samples to meet NACE requirements.

The chemical commonly abbreviated H₂S. This deadly poison also has a destructive effect on high strength low alloy steels when the hardness of these steels exceeds a hardness of 22 Rockwell C.

A hardened pointed or rounded contact object used to impress an indentation into the surface of steel (or other metal) parts in order to obtain a Hardness measurement of that part. See HBW, HRC, and HRB.

Measured aspects of Material used to describe its elastic and inelastic reaction to applied force; These may include Tensile Strength, Yield Strength, Elongation, Reduction of Area, Impact Strength and Hardness.

A document published by the National Association of Corrosion Engineers defining the specific limits of chemistry, hardness and microstructure of Materials used to make equipment to contain or control well production fluids that include hydrogen sulfide.

A designation of hardness of metallic materials measured by pressing a small rounded indenter against a clean prepared surface with a specific force. The machine making the indention also measures the depth of the indention and provides a numerical value for that depth. The Rockwell B scale expresses more accuracy in the hardness measurement of metallic materials softer than HRC 20. To convert hardness numbers between measuring methods and scales, see Hardness Number Conversion Chart.

A designation of hardness, usually of steel or Corrosion Resistant Alloys , measured by pressing a specially shaped indenter against a clean prepared surface with a specific force. The machine making the indention also measures the depth of the indention and provides a numerical value for that depth. This numerical value relates to steel Tensile Strength and NACE Standard MR0175 references hardness in determining steel’s suitability for use in H2S Service. To convert hardness numbers between measuring methods and scales, see Hardness Number Conversion Chart.

22 RC, 99 RB, 237 HBW (read 235 in table), and 248 HV represent the important upper hardness limit for non austenitic steel for H2S service specified in NACE MRO175 and referenced in API Spec 6A. Some authorities may offer slightly different equivalent hardness numbers.

Hardness conversion table - Tensile strength, Vickers, Brinell och Rockwell

(According to DIN 50150)

The information below is for guidance only and should not be seen as fixed reference values. Some conditions , especially the incidence of cold work , can change the relationship between the tensile strength and hardness profoundly.

Vickers: F ≥ 98N, diamond pyramid (HV)

Brinell: F = 29 421 N, ball ø 10 mm (HB)

Rockwell: F = 980 N, ball 1/16" (HRB)

Vickers: F ≥ 98N, diamond pyramid (HV)

Brinell: F = 29 421 N, ball ø 10 mm (HB)

Rockwell: F = 1471 N, diamond cone (HRC)