... tempering steel, as well as the general chilled cast iron, pearlitic malleable iron, titanium, etc.; hardness value of more than ... surface of hardened steel, thin hard steel, pearlitic malleable iron.Diamond indenterD100CCast iron, aluminum, magnesium alloy, bearing alloys.1/8 ... mild steel sheet.1/16 steel ballF60BBronze, phosphor bronze, malleable iron, etc. (HRB value of nearly 100 materials).1/16 ...