Which hardness test uses both a minor and major load?

The Rockwell hardness test is unique because it employs both a minor and major load during the process of measuring hardness. Initially, a minor load is applied to establish a baseline indent on the material being tested. This initial load is light enough to create a small indent that serves as a reference point. Following this, a major load is applied that is significantly heavier, causing a more pronounced indent in the material. Once the major load is removed, the residual depth of the indent created by the major load is measured. This depth is then compared to the baseline from the minor load to determine the Rockwell hardness value.

This testing method is widely used due to its efficiency and the direct relationship it shows between the load applied and the hardness of the material, enabling quick assessment in various industrial applications. Other hardness tests, like Brinell and Mohs, utilize different methodologies that do not involve the application of both minor and major loads, making Rockwell distinct in this regard.