BrinellPrüfung
BrinellPrüfung is a hardness testing method used to determine the indentation hardness of a material. It is one of the oldest and most widely used hardness tests. The test involves pressing a hardened steel or carbide ball of a specified diameter into the surface of the material being tested under a specific load. The ball is held under this load for a specified dwell time. After the load is removed, the diameter of the resulting indentation is measured. The Brinell hardness number (BHN) is calculated by dividing the applied load by the surface area of the indentation. The formula for calculating the Brinell hardness number is BHN = (2 * F) / (π * D * (D - sqrt(D^2 - d^2))), where F is the applied load in kilograms-force, D is the diameter of the ball indenter in millimeters, and d is the average diameter of the indentation in millimeters. BrinellPrüfung is suitable for testing a wide range of materials, including metals, alloys, and plastics, especially those with a relatively coarse grain structure. The test is non-destructive in the sense that the indentation is typically small and does not significantly affect the material's subsequent use. However, it does leave a permanent mark. The choice of ball diameter and applied load depends on the material being tested and the desired accuracy. Standard conditions are often used for comparability of results. Brinell hardness values can be correlated to other material properties, such as tensile strength.