Mikrohårdhetsprov

Mikrohårdhetsprov, also known as microhardness testing, is a technique used to measure the hardness of small areas of a material. This method is particularly useful for materials that are too thin or too small for conventional hardness testing methods. The most commonly used microhardness testing method is the Vickers hardness test, which involves pressing a diamond indenter into the material with a known load. The hardness is then calculated based on the size of the indentation left by the indenter.

The Vickers hardness test uses a diamond pyramid indenter with a square base and an included angle of 136 degrees between the opposite faces. The load applied to the indenter can range from 1 gram-force to 1 kilogram-force, with the most commonly used loads being 100 grams-force and 300 grams-force. The hardness number (HV) is calculated using the formula:

HV = 1.854 * P / d^2

where P is the applied load in kilograms-force and d is the average diagonal length of the indentation in millimeters.

Microhardness testing is widely used in materials science and engineering to characterize the mechanical properties of materials, such as hardness, strength, and toughness. It is also used to evaluate the quality of materials, such as metals, ceramics, and polymers, and to assess the effects of heat treatment, cold working, and other processing techniques on material properties.