This is a dynamic indentation hardness test, which uses a calibrated instrument that drops a diamond-tipped hammer from a fixed height onto the surface of the material being tested.
Diamond-Tipped Hammer
Scleroscope hardness number, HSc or HSd, is a number related to the height of rebound of the hammer. It is measured on a scale determined by dividing the average rebound of the hammer from a quenched (to maximum hardness) and untempered high-carbon water-hardening tool steel test block of AISI W-5 into 100 units .
