See further information about Materials and Corrosion Management, or please contact us. BS 860:1967'Tables for comparison of hardness scales' BSI, London.ASTM International, West Conshohocken, PA, ASTM E140: 2012'Standard hardness conversion tables for metals relationship among Brinell hardness, Vickers hardness, Rockwell hardness, Superficial hardness, Knoop hardness Scleroscope hardness and Leeb hardness'.BS EN ISO 18265:2013'Metallic materials - Conversion of hardness values'.

Some other hardness scales are included in the standards, but these are used less often.Ī useful conversion used extensively in applications involving H 2S is that 22 HRC (Rockwell C) is equivalent to 248 HV (Vickers), which is often rounded to 250 HV.Īn earlier standard, BS 860:1967, which has been superseded by BS EN ISO 18265:2003 gives the following equation for hardness conversion between Brinell and Vickers scales.Īs with all conversions, it must be appreciated that the conversion between hardness scales is approximate, not absolute. The conversions for these standards are not exactly the same, but are similar, incorporating Vickers, Brinell, Rockwell B, and Rockwell C hardness scales, and conversions for a limited number of material types. Two such standards are BS EN ISO 18265:2013, and ASTM E140: 2012. These have arisen from many hardness readings, the values have been plotted and a conversion established. However, a few national standards do list hardness conversion tables, and related equations. There is no direct, universally used correlation between the different hardness scales. National Structural Integrity Research Centre.Structural Integrity Research Foundation.As a guide we show the theoretical conversion comparison of tonnes tensile in Newtons/mm and MPa to steel hardness. Because of the wide range of variation among different materials, it is not possible to state confidence limits for the errors in using a conversion chart. Steel hardness conversion table containing conversion factors for Rockwell, Vickers & Brinell. Since the various types of hardness tests do not all measure the same combination of material properties, conversion from one hardness scale to another is only an approximate process. Reference table: Steel Hardness conversion chart

Vickers to rockwell conversion