The Rockwell Hardness test is a hardness measurement based on the net increase in depth of impression as a load is applied. Hardness has been variously defined as resistance to local penetration, scratching, machining, wear or abrasion, and yielding. The multiplicity of definitions, and corresponding multiplicity of hardness measuring instruments, together with the lack of a fundamental definition, indicates that hardness may not be a fundamental property of a material, but rather a composite one including yield strength, work hardening, true tensile strength, modulus of elasticity, and others. The Rockwell hardness test method consists of indenting the test material with a diamond cone or hardened steel ball indenter