The working principle of a Brinell hardness tester is to press a steel ball of a certain diameter into the surface of a sample at a certain speed under a certain test force. After a specified holding time, the test force is removed. The Brinell hardness value of the metal is expressed as the average pressure on the spherical surface area of the indentation.
The Brinell hardness tester is mainly used for hardness determination of materials such as cast iron, steel, non-ferrous metals, and soft alloys. The Brinell hardness test produces the largest indentation among all hardness tests. It reflects the comprehensive properties of the material and is not affected by microsegregation or compositional inhomogeneity of the sample structure, making it a highly accurate hardness testing method.