Microstructure evolution in adiabatic shear band (ASB) in the peak aged ZK60 magnesium alloy cylindrical tube specimen after explosive radial compression was systematically investigated. High strain rate compression tests were performed by means of the radial collapse of thick-walled cylinder technique to achieve nominal strain rates of about 10⁴ s⁻¹. The TEM results indicate that the elongated grains and deformed twins are the major characteristics in the boundary of the shear band. The central region in ASB was found to consists of ultrafine and equiaxed grains with a typical size of 100 nm. And it was found that precipitates within ASB were significantly reduced, namely the precipitates instantaneous dissolution during adiabatic shearing. It is proposed that fine equiaxed grains within ASB are the result of rotational dynamic recrystallization during localization. The free energy difference between the precipitates and matrix provided a thermodynamic condition for the dissolution of precipitates. Diffusion rate increased due to high strain rate, high shear stress (large strain) and adiabatic temperature rise, which caused instantaneous dissolution of precipitates.

系统地研究了爆炸性径向压缩后峰值时效ZK60镁合金圆柱管试样在绝热剪切带（ASB）中的组织演变。通过厚壁圆筒技术的径向塌陷进行了高应变率压缩测试，以实现约10 ⁴  s ^-1的名义应变率。TEM结果表明，拉长晶粒和变形孪晶是剪切带边界的主要特征。发现ASB的中心区域由典型尺寸为100 nm的超细晶粒和等轴晶粒组成。并且发现ASB内的沉淀物显着减少，即在绝热剪切过程中沉淀物的瞬时溶解。有人提出，ASB内的细等轴晶粒是局部化过程中旋转动态再结晶的结果。沉淀物和基质之间的自由能差为沉淀物的溶解提供了热力学条件。由于高应变速率，高剪切应力（大应变）和绝热温度升高，扩散速率增加，这导致了沉淀物的瞬时溶解。