搅拌摩擦加工AZ31超细晶镁合金超塑性行为  

Superplastic behavior of ultrafine grained AZ31 magnesium alloy by friction stir processing

作　　者：乔柯 王晨曦[2] 刘明霞 李海燕 陈善勇 吴冰 QIAO Ke;WANG Chen-xi;LIU Ming-xia;LI Hai-yan;CHEN Shan-yong;WU Bing(Shaanxi Key Laboratory of Surface Engineering and Remanufacturing,School of Mechanical and Material Engineering,Xi'an University,Xi'an 710065,China;School of Metllugical Engineering,Xi'an University of Architecture and Technology,Xi'an 710055,China)

机构地区：[1]西安文理学院机械与材料工程学院陕西省表面工程与再制造重点实验室,陕西西安710065 [2]西安建筑科技大学冶金工程学院,陕西西安710055

出　　处：《塑性工程学报》2021年第4期105-111,共7页Journal of Plasticity Engineering

基　　金：国家自然科学基金资助项目(51274161,51404180);陕西省自然科学基金资助项目(2019JQ-769,2019JQ-111);陕西省表面工程与再制造重点实验室天元开放基金资助项目(tywl2019-05)。

摘　　要：采用搅拌摩擦加工(Friction Stir Processing,FSP)制备了超细晶AZ31镁合金,研究了温度和应变速率对超细晶AZ31镁合金高温超塑性行为的影响。结果表明,FSP制备的超细晶镁合金平均晶粒尺寸为0.65μm。随着变形温度升高和应变速率降低,FSP加工区域的晶粒粗化。当应变速率为0.01 s-1时,在温度为300、350和400℃条件下材料的伸长率均大于200%,这表明FSP制备的超细晶镁合金具有良好的高应变速率超塑性。在温度为450℃,应变速率为0.003 s-1时,超细晶镁合金的伸长率达到1090.8%。超细晶AZ31镁合金在高温拉伸条件下的变形机制主要为晶界滑移,在晶界滑移过程中,晶界处产生孔洞,孔洞汇集使试样发生断裂。The friction stir processing(FSP)was used to fabricate the ultrafine grained AZ31 magnesium alloy.The effects of temperature and strain rate on high-temperature superplastic behavior of ultrafine grained AZ31 magnesium alloy were studied.The results show that the average grain size of ultrafine grained magnesium alloy prepared by FSP is 0.65μm.With the increase of deformation temperature and the decrease of strain rate,the grain in FSP processing area coarsens.When the strain rate is 0.01 s-1,the elongation of material is more than 200%at 300,350 and 400℃,which indicates that the ultrafine grained magnesium alloy prepared by FSP has good high strain rate superplasticity.When the temperature is 450℃and the strain rate is 0.003 s-1,the elongation of ultrafine grained magnesium alloy reaches 1090.8%.The deformation mechanism of ultrafine grained AZ31 magnesium alloy under the condition of high temperature tension is mainly grain boundary sliding.During the process of grain boundary sliding,holes are formed at the grain boundary,and holes gather makes the sample fracture.

关 键 词：搅拌摩擦加工 超细晶 镁合金 超塑性 晶界滑移 

分 类 号：TG306[金属学及工艺—金属压力加工]