Herbert pendulum method

Herbert pendulum method

[′hər·bərt ′pen·jə·ləm ‚meth·əd]
(metallurgy)
Hardness testing in which a 1-millimeter steel or jewel ball resting on the surface to be tested acts as the fulcrum for a 4-kilogram compound pendulum of 10-second period; the swinging of the pendulum causes a rolling indentation in the material, and several hardness factors, such as work hardenability, are determined.