在高速车轴DZ2（模铸）钢的边部切取10×10×8的镜像样品，在国产UltrMet6型预磨机上进行预磨，然后在150、320、600和1000号砂纸上依次水磨后，在PG-2C型抛光机上进行机械抛光，抛光后的试样置于4 ml 硝酸（HNO₃） + 96 ml 无水乙醇（CH₃CH₂OH）混合溶液浸蚀10~15 s，在Olympus GX53光学显微镜中观察其金相组织，如图所示，由图可知试样中组织基本为回火马氏体，

A mirror sample of 10×10×8 was cut from the edge of high-speed axle DZ2 (die cast) steel, which was pre-ground on domestic UltrMet6 pre-grinding machine, and then water ground on sandpaper 150, 320, 600 and 1000 in turn, and then mechanically polished on PG-2C polishing machine. After polishing, the sample was immersed in a mixed solution of 4 mL nitric acid (HNO3) + 96 ml anhydrous ethanol (CH3CH2OH) for 10~15 s, and its metallographic structure was observed under Olympus GX53 optical microscope, as shown in the figure. It can be seen from the figure that the microstructure of the sample is basically tempered martensite.