中文摘要：

为了解不同道次等通道转角挤压（ECAP）对材料拉伸屈服和硬化的作用,以纯铜棒材试样为研究对象,实验研究了经多道次ECAP后材料的单轴拉伸屈服和硬化行为,并进一步探讨了退火对ECAP后材料力学性能的影响,得到以下结论：①挤压道次相同的情况下,经退火/空冷处理后材料硬化更为充分;②一道次挤压对材料的硬化作用远大于后续道次;③在材料挤压后实施了退火的情形,四道次后的挤压对材料不再有明显的硬化作用。这一研究有助于人们更深入地了解ECAP对材料力学行为的影响。

英文摘要：

In order to investigate the influence （ECAP） on the yielding and hardening of a metal, the experimental investigations on the yielding and of muhi-pass equal channel angular pressing pure copper was used as hardening behavior of the a target material, and material samples after multi-pass of ECAP were carried out. The analyses of influence on the mechanical characteristics of annealing after ECAP were conducted. The main conclusions are： （1） more strengthening can be ex- pected if annealing / air-cold treatment is adopted under the condition that the ECAP pass number is the same; （2） the strengthening effect of the first pass of ECAP is much greater than that of the sub- sequent ECAP passes; （3） if the annealing treatment is applied, the strengthening effect due to ECAP after four passes will be very small. These results are helpful for people to understand the in- fluence of multi-pass ECAP on the mechanical behavior of metals.