一种新的等通道转角分流挤压ZK60镁合金的微观组织和性能  

Microstructural and mechanical properties of ZK60 magnesium alloy subjected to equal channel angular porthole extrusion

作　　者：侯江华[1] 段翠芳[1] 

机构地区：[1]河南机电高等专科学校机电系,新乡453002

出　　处：《塑性工程学报》2015年第3期49-53,共5页Journal of Plasticity Engineering

基　　金：河南省重点科技攻关计划资助项目(122102210256)

摘　　要：在传统等通道转角挤压(ECAP)基础上提出了一种新型等通道转角分流热挤压技术(ECAPP)。该工艺可有效用于航空用轻质镁合金螺栓棒材的原料制备,并具有较好的晶粒细化效果。工件的晶粒尺寸大小和均匀性分布表明ECAPP工艺具有实际意义。相对于传统工艺,ECAPP工艺每道次提供更多的应变量,且挤出相同的产品时需要较小的挤压载荷。通过光学显微镜分析了晶粒尺寸,通过TEM分析了合金在该工艺的变形过程中的微观组织细化和再结晶机理。合金的强度和硬度随工艺道次的增加而快速增加。但第3道次后,其拉伸强度和硬度增加程度较小;且3道次后晶粒细化程度不再增加。This paper aims to provide an introductory insight about＂Equal Channel Angular Porthole Extrusion＂（ECAPP）,a counterpart of＂Equal Channel Angular Extrusion＂（ECAP）.The process is implemented to refine the microstructure of magnesium bar material for bolt in aviation industry.The comparisons of average grain size and process loads reveal the advantages and shortcomings of ECAPP with respect to ECAP.ECAPP shares a relatively similar geometry of forming dies with that of ECAP.The advantages of the ECAPP are：1）more effective strains attainable per pass;2）less load needed for a given specimen size.Nonetheless,less homogeneous strain per pass is observed in case of ECAPP.OM and TEM inspections revealed the remarkable refinement of the microstructure throughout the process and also the recrystallization at the final passes.Hardness,tensile strength and grain size refinement tend to increase to a limiting value through 3successive passes beyond which there appeared a unchanged tendency associated with observed intense recovery and the recrystallization.

关 键 词：ECAPP ZK60镁合金 微观组织 性能 

分 类 号：TG132.3[一般工业技术—材料科学与工程]