Rockwell scale for specialized applications. There are special scales for measuring case-hardened specimens. 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
182 Cumberland Street, The Rocks The place is important in demonstrating the course, or pattern, of cultural or natural history in New South Wales. This shop and residence 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 building is part of the Rocks Conservation Area and, as such, contributes to the overall character and interpretation of the area. It is one of the few remaining corner shops and residences within the area.