The definition of hardness testing is 'a test to determine the resistance a material exhibits to permanent deformation by penetration of another harder material.
What is the purpose of hardness testing?
The purpose of the hardness test is to determine the suitability of a material for a given application, conformance to a specification, standard, or particular treatment to which the material has been subjected (heat treatment, thermal process).
There are three main types of hardness measurements: scratch, indentation, and rebound. Within each of these classes of measurement there are individual measurement scales.
What are the three methods of testing hardness?
Common hardness testing types include Rockwell (indentation depth or un-recovered indentation), Knoop/Vickers, and Brinell (area of indentation). Rockwell testing is the most commonly used method by virtue of the quick results generated and is typically used on metals and alloys.
Why is the hardness test used for material evaluation?
Hardness testing is widely used for material evaluation because of its simplicity and low cost relative to direct measurement of many properties. Specifically, conversion charts from Rockwell hardness to tensile strength are available for some structural alloys, including steel and aluminum.