Rockwell Hardness Test
Definition - What does Rockwell Hardness Test mean?
Rockwell Hardness Test is a material hardness scale test which is used to determine the hardness of a material by making indentations on the surface of the material. The indentations are made with the help of an intender and the fixed amount of force produced by a loader. The hardness is measured on the surface of the material by measuring the depth of the indentation marks made by the intender on the application of fixed amount of force. The indentations are made at various locations on the material and a measure of each indentation depth is performed to check the hardness. The lower the depth, the harder the material is.
Petropedia explains Rockwell Hardness Test
This test is conducted to ensure necessary thickness, hardness and strength of the materials used for the development of oil and gas industry infrastructure. Rockwell hardness test is performed as per ASTM E-18 standard specifications and is one of the most commonly employed material hardness test. This test is usually easy to perform and generates accurate results. The intender used for making indentation is made of diamond as it is the hardest material known to mankind. This test is applicable to all the metals, except for these conditions:
- Wherever, there is too much variation on the metal surface or the structure is there, this test is not applied, or
- Wherever, a metal sample shape and size prohibits its use.
Across the sample metal sheet that needs to be checked for the hardness, a fixed amount of force is applied at multiple locations and indentation marks are made by indenter. The depths of indentations are measured at all the places. The indentation hardness correlates linearly with the tensile strength of the material.