noun
Rockwell hardness
A measure of material hardness determined by the depth of indentation under a specific load, commonly used in engineering and materials science.
この鋼材のロックウェル硬さはHRC60です。
The Rockwell hardness of this steel is HRC60.
Vickers hardness uses a diamond indenter and is suitable for thin materials or coatings, while Rockwell hardness is faster and more common for bulk metals.
Brinell hardness uses a larger ball indenter and is often used for castings and forgings, whereas Rockwell is more convenient for finished parts.
From English 'Rockwell hardness', named after Stanley P. Rockwell, combined with Japanese 硬さ (hardness).