The Brinell Hardness Test is a method of determining hardness in materials, primarily metals, whereby the ability of a material is measured to resist indentation. A hardened steel or tungsten carbide ball is pressed against the surface of the material with a definite load, after which the size of the indentation is measured.

Key Features:

• Procedure: A ball, made of steel or tungsten carbide and usually 10 mm in diameter, is forced into the surface of the material under a standardized load of 500 to 3000 kgf for a known period. The diameter of indentation left on the material is then measured to calculate the Brinell Hardness Number (BHN).

• Calculation of Measurement: The BHN is determined by the following equation:

          BHN= πD(D−D2−d2)2P where P is the load applied, D is the diameter of the ball, and d is the            diameter of the indentation.

• Applications: The test is most common for materials with coarse microstructure such as castings and forgings, so average hardness over a larger surface area can be obtained to decrease errors caused by material inconsistencies.

This test is significant in determining hardness, giving an idea of various mechanical properties of materials thus allowing the industries to assure the quality and durability of the materials. It finds application in various industries, from manufacturing to metallurgy to engineering, to test the strengths and wear resistances of metals. However, while being the test of choice for bulk testing of steel, aluminum, and iron, it does not apply to very hard or very thin materials. Recent advances in digital imaging and automation have only improved the accuracy and speed of the Brinell hardness test, allowing it to serve as a key quality control methodology across industries today.