Rockwell scale Rockwell scale The Rockwell scale is a hardness scale based on indentation hardness of a material. The Rockwell test determines the hardness by measuring the depth of penetration of an indenter under a large load compared to the penetration made by a preload. There are different scales, denoted by a single letter, that use different loads or indenters. The result is a dimensionless number noted as HRA, HRB, HRC, etc., where the last letter is the respective Rockwell scale (see below). When testing metals, indentation hardness correlates linearly with tensile strength. This important relation permits economically important nondestructive testing of
NSW Housing Board Building, Gloucester Street, The Rocks have been removed and replaced. Interior wall and floor tiling and all the sanitary fixtures have been removed. As at 30 March 2011, the NSW Housing Board Building and site are of State heritage significance for their historical and scientific cultural values. The site and building are also of State heritage significance for their contribution to The Rocks area which is of State Heritage significance in its own right. The Model Factory and Workers Dwelling at 120 Gloucester Street, The Rocks and site is of State heritage significance for its historical, aesthetic and scientific cultural values. The site and building