The Brinell Hardness Test is the oldest method of hardness testing commonly used today. The Brinell test was invented in Sweden by Dr. Johan August Brinell in 1900. This test is often used to determine the hardness of castings and forgings whose grain structure is too course for accurate Rockwell or Vickers testing. Almost all metals may be tested with the Brinell test by simply varying the ball size and test force. As long as the ball size to test force ratio remains constant, the results are considered accurate.
Results from the Brinell Hardness Test are used extensively in industry as a basis of acceptance of commercial shipments, and for quality control purposes generally. These result may correlate with metallic characteristics such as: ductility, tensile strength, wear resistance, etc.
The Brinell Test is an indentation hardness test consisting of two steps. Step one, the indenter is brought in contact with the tests specimen perpendicular to the surface and the specified test force is applied. The test force held for the specified time and then withdrawn. Step two, The diameter of the indentation is measured in at lest two directions perpendicular to each other. The Brinell hardness value is computed from the mean of the diameter measurements by the use of a mathematical formula designed for this purpose, or more frequently from a chart based on the formula.
The complete ASTM E 10 Standard Test Method for Brinell Hardness of Metallic Materials may be obtained from ASTM International.