6.hardness 6.1 brinell hardness testing is optional unless requested by the purchaser.the Brinell Hardness of a lot shall be the average of the hardness determinations on each button prepared as described in 7.1.2.the average hardness of each button for the lot shall not exceed the values specified in Table 1. measurement shall be in accordance with Test Method E10,using a 0.394 in.(10-mm)ball,3307-1bf(1500-kgf) load,and 30-s dwell.