40CrNi2Mo钢绝热剪切带的微观特征

Microstructural characteristic of the adiabatic shear band in 40CrNi2Mo steel

通过金相显微镜、扫描电子显微镜和透射电子显微镜的观察,对不同回火温度下40CrNi2Mo钢在弹丸侵彻下产生的绝热剪切带的微观特征进行研究。结果表明:此试验条件下的绝热剪切带宽为10～40μm,可分为过渡区和中心区;过渡区为严重形变后拉长的马氏体板条,而中心区发生了相变,形成了细小的等轴晶结构。

The microstructural characteristic of adiabatic shear band during projectile perforation in 40CrNi2Mo steel tempered at different temperatures has been studied by optical metallographic microscope, scanning electron microscope and transmission electron microscope. The results show that the width of the adiabatic shear band is about 10-40 μm, and it consists of two areas ： the transition area and the center area. The transition area is composed of heavily distorted martensite laths, while in the center area equiaxed grains are formed after phase transformation.