(西北工业大学 航空学院，西安 710072)
摘 要: 以99.9%的高纯铝为实验材料，利用等径通道转角挤压技术制备超细晶铝，研究其在77~473 K温度范围内的准静态和动态压缩力学性能，并研究晶粒细化对纯铝应变硬化行为及其温度和应变率敏感性的影响。结果表明：晶粒细化导致准静态压缩时纯铝应变硬化能力丧失，甚至在较高实验温度下出现应变软化。此外，材料力学行为的温度和应变率敏感性也显著升高。随着实验温度的升高，材料力学行为的应变率敏感性显著增大。
关键字: 超细晶铝；等径通道挤压；力学性能；应变率敏感性；温度敏感性；应变软化
（School of Aeronautics, Northwestern Polytechnical University, Xi’an 710072, China）
Abstract:An available aluminum with a purity of more than 99.9% (mass fraction) was used to produce ultra-fine grained aluminium (UFG-Al) by equal channel angular pressing (ECAP) method. The mechanical behaviour of UFG-Al at temperatures ranging from 77 to 473 K under quasi-static and dynamic compression was investigated. The effects of grain refinement on the strain hardening behavior, temperature and strain rate sensitivities of mechanical properties of pure aluminum were studied. The grain refinement leads to the lost of stain hardening abilities, and the corresponding temperature and strain rate sensitivities also significantly increase. Meanwhile, as the temperature rises, the strain rate sensitivity of mechanical properties increases significantly.
Key words: ultra-fine grained aluminum; equal channel angular pressing; mechanical behaviours; strain rate sensitivity; temperature sensitivity; strain softening
