1. The ability of a surface to absorb energy imparted by an object colliding with it, or its shock absorbing properties.
Schematic description of Rockwell Hardness Testing. Rockwell Formula: Hardness Rockwell HR = E – e. “E” is a constant of 100 (diamond) or 130 (ball) units. “e” is the penetration depth in units of 0.002mm.