## Materials Science and Engineering: An Introduction

$d = 1.45 mm$
Given: 10-mm diameter Brinell hardness indicator produced an indentation of 2.50 mm in diameter in steel alloy when load of 1000 kg was used Required: diameter of indentation to yield hardness of 300 HB when 500-kg load is used Solution: Using equation for HB in Table 6.5: $d = \sqrt D^{2} - [D - \frac{2P}{(HB)πD}]^{2} = \sqrt (10 mm)^{2} - [(10 mm) - \frac{2 (500 kg)}{(300)π(10 mm)}]^{2} = 1.45 mm$