indentation diameter
The impression diameter is the diameter of the circular mark left on the surface during ball indentation testing. It is used for hardness calculation.
Physico-chemical Mechanism of Action
Ball indentation testing presses a hard ball into the metal part, leaving an impression. The diameter of this impression (impression diameter) indicates how deep the indentation is.
Metallurgical Relevance & Welding Risks
An impression diameter that is too large can indicate hardness that is too high or too low. Too high hardness leads to cracks and breakage, while too low hardness reduces service life. Correct hardness is crucial for mechanical strength and behavior under load.
Workshop Practice & Procedures
Measure the impression diameter with a micrometer exactly on the surface of the impression. Then compare the measured value with the specific hardness limits for the material and application. If there are deviations, check the welding parameters and adjust them as needed to achieve the desired hardness.