Optical Hardness Measurement
Optical hardness testing is a visual or camera-based analysis of test indentations under a microscope. It is mainly used in Vickers and Brinell hardness tests.
Physicochemical Mechanism of Action
Optical hardness testing involves visual or camera-based evaluation of the remaining diagonals or diameters of test indentations under a microscope. This method is based on measuring the indentation caused by pressing a heavy body into the metal crystal.
Metallurgical Relevance & Welding Risks
Optical hardness testing is crucial for the quality assurance of welds. An inaccurate measurement can lead to errors in the strength and toughness of the material, which poses risks in the use of components. A faulty indentation or misinterpretation can result in an overestimated or underestimated hardness.
Workshop Practice & Instructions
For optical hardness testing, use a high-resolution microscope and a suitable test indenter. The measurement should be performed in a clean environment to ensure that no disturbances or discolorations affect the result. The diagonal of the indentation is measured with a micrometer screw and the hardness is calculated using a standard hardness reference scale.