Ceramic Hardness Testing

The purpose of hardness testing for ceramic coatings.

Ceramic hardness testing.

Hardness is one of the most frequently measured properties of a ceramic. Vickers hardness is a resistance value obtained by pressing a diamond indenter onto a test specimen. The grading of the scale ranges from 0 to 9 and the h indicates the hardness of that specific grade. Hardness is a representation of a material s resistance to localised plastic deformation.

The mechanical property of a material s hardness is defined as a specific and calculable measure of how resistant a material is to compressive force. An indenter of well defined geometry is pressed into the surface of the sample under a. Hardness testing is frequently used for characterizing mechanical properties of engineering ceramics. In this test a pyramidal diamond indenter is pressed into a polished surface under known loading conditions and the size of the indentation is related to the hardness of the material.

The hardness of fine ceramics is generally indicated using a vickers hardness number. The pencil scale is a test of hardness that helps to explain to consumers how hard the ceramic coating will be once it s cured to the surface. Hardness testing of ceramics hardness testing has many pitfalls but good metrological procedures and the use of srms would help to improve the accuracy of conventional tests.