Rockwell Hardness

The three steps illustrated below are needed to obtain the Rockwell Hardness number for a sample.

(1) Apply Pre-load and set
scale to the pointer

(2) Apply the Major Load and
wait until the pointer comes to
rest,

From: Wakil, "Materials Science & Engineering Lab. Manual" PWS (1994)

(3) Remove the Major Load and read the pointer position on the indenter dependent
hardness scale. For this case, which uses the diamond indenter and a 150 Kg total load, the Rockwell hardness is a C-scale number.