Micro Hardness Evaluation

Micro hardness evaluation of coatings is done to ascertain the achievement of desired hardness values of coating material. The output of this test can be further used for optimizing spray parameters and for quality control purposes. Same coating material applied with different process and different technique can exhibit varying micro hardness. It is believed that micro hardness evaluation enable quick estimation of coating strength and the quality of spraying because defects such as non-melted particle inclusions and porosity lower micro hardness. Inherent in this usage is the assumption that hardness is a measure of quality. Micro hardness is often used for the first approximation of coating wear resistance, which is by far the most important property in application of Thermal spray technology.