超细亚晶粒铝合金的强化机理  

Strengthening mechanism of ultra-fine sub-grained Al alloy

作　　者：徐红星[1] 程晓农[1] 许晓静[2] 宋刚[1] 莫纪平[2] 

机构地区：[1]江苏大学材料科学与工程学院,江苏镇江212013 [2]江苏大学机械工程学院,江苏镇江212013

出　　处：《江苏大学学报（自然科学版）》2011年第1期51-55,共5页Journal of Jiangsu University：Natural Science Edition

基　　金：江苏省自然科学基金重点资助项目(BK2007707);江苏省科技成果转化专项基金资助项目(BA2005054)

摘　　要：在室温下对经过时效处理的2024铝合金实施了等效应变为0.5的等通道转角挤压(ECAP)变形,将形变强化、时效强化和晶界细化强化有机结合,制备出超细亚晶粒铝合金,其硬度、屈服强度、伸长率分别约达100 HV,130 MPa和31%.分析探讨了超细亚晶粒2024铝合金的强化机理.研究结果表明,屈服强度的实测数值和理论计算所得十分吻合,由此证明,过时效态2024铝合金经ECAP加工后,其屈服强度主要取决于基体的屈服强度,并且主要由位错强化、亚晶界强化、晶界强化和晶格摩擦应力等4部分组成.Equal-channel angular pressing（ECAP） of the 2024 Al alloy treated by overaging treatment was performed at room temperature with an imposed equivalent strain of 0.5.The hardness of 100 HV,yield strength of 130 MPa and elongation rate of 31% aluminum alloys were obtained for the ECAPed alloy.The strengthening mechanism was analysed.The results show that the yield strength of measured and calculated values agree very well.It is proved that the yield strength of 2024 aluminum alloy by overaging solution after ECAP processing depends primarily on the matrix yield strength,which mainly includes dislocation strengthening,subgrain boundary strengthening,grain boundary strengthening and lattice friction stress.

关 键 词：铝合金 超细亚晶粒 等通道转角变形 亚晶界强化 位错强化 

分 类 号：TG113.25[金属学及工艺—物理冶金] TG146.21[金属学及工艺—金属学]