本厂在曲轴的生产过程中,每炉次均浇注抗拉试棒,为了测量试棒的布氏硬度,将抗拉试验后试棒的夹持部分两端车平、磨平(φ25mm×20mm),再进行硬度试验,然后将试样放于圆环(外径φ58mm,内径φ32mm,高20mm)中,用读数显微镜测量压痕直径大 The factory in the crankshaft production process, each furnace were cast tensile bars, in order to measure the Brinell hardness of the test bar, the tensile test after the test section of the grip on both ends of the car level, polished (φ25mm × 20mm ), And then the hardness test, and then put the sample on the ring (diameter φ58mm, diameter φ32mm, height 20mm), using a reading microscope to measure the indentation diameter