Rockwell Hardness
Rockwell hardness measures the hardness of a material by the penetration depth of a cone or ball under preliminary and main load. Hardness is read directly from the residual depth.
Physical-Chemical Mechanism
Rockwell hardness testing measures how deep a cone or ball penetrates the material under a preliminary load and then a major load. The difference between these two depths tells you how hard the material is.
Metallurgical Relevance & Welding Risks
Too high Rockwell hardness can cause cold cracks or hot cracks because the material won't give. Too low hardness can lead to deformation and poor strength.
Shop Practice & Action Steps
For Rockwell hardness testing, use a Rockwell hardness tester with the right cone or ball indenter. Apply the preliminary load, then the major load, and note the penetration depth. Compare the result with the material's specific hardness requirements.