Rockwell Hardness Testing 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, where A is the scale letter.
Brinell Hardness Testing The Brinell method is primarily used to test forgings and castings made of steel and iron. The Indentor is usually a steel ball, 10mm in diameter. Standard loads range from 500 to 3,000 kilograms. The full load is applied for 10 to 15 seconds in the case of iron and steel, and for 30 seconds in the case of many other metals. The diameter of the impression is spherical, and its depth is proportional to the square of its diameter. This relationship is used to determine hardness.
