铈对AZ91D镁合金ECAP组织及性能的影响  

Effect of Cerium on Microstructure and Mechanical Property of ECAP AZ91D Alloy

作　　者：史菲[1,2] 贾倩[1] 郭学锋[2] 张忠明[2] 

机构地区：[1]哈尔滨工业大学(威海)材料科学与工程学院,山东威海264209 [2]西安理工大学材料科学与工程学院,陕西西安710048

出　　处：《铸造技术》2010年第11期1479-1481,共3页Foundry Technology

基　　金：国家自然科学基金资助项目(50271054);陕西省自然科学基金资助项目(2002E110);陕西省教育厅回国留学人员基金资助项目

摘　　要：通过普通凝固技术获得含有0.1%,0.3%,0.5%,0.7%和0.9%Ce的AZ91D镁合金,进行等通道转角挤压(ECAP)实验。利用金相显微镜(OM)、扫描电镜(SEM)观察合金微观组织形貌,用扫描电镜附带的能谱分析仪(EDS)分析其微区组织成分,并测试挤压前后合金的维氏硬度。结果表明,适量Ce的加入可使AZ91D合金在晶界处析出Al4Ce金属间化合物,阻碍基体相生长而细化合金显微组织;Ce量影响Al4Ce金属间化合物的形貌。Ce<0.5%时,Al4Ce相呈颗粒状析出。而Ce>0.5%时,Al4Ce相呈杆状或片状生长;Ce能显著提高AZ91D合金室温硬度;ECAP后合金的强化效果更佳,其中三次挤压后的AZ91D-0.5%Ce合金维氏硬度提高了近1倍。The alloys of AZ91D with 0.1%,0.3%,0.5%,0.7% and 0.9%Ce were obtained by as-cast technique. And then,AZ91D-x%Ce alloys were squeezed by ECAP. The microstructures of samples were analyzed by optical microscope（OM） and scanning electron microscope（SEM）. The composition and phases of the alloys were analyzed by EDS. The results show that Al4Ce phase is produced when adding Ce into AZ91D alloy. The right amount of Ce can decrease the grain size of α-Mg matrix. And the amount of Ce affects the microstructures of Al4Ce phase. There are granular （Ce0.5%） and plate-shaped particles （Ce0.5%）. Adding Ce can increase the hardness of AZ91D magnesium alloys at RT. After ECAP 3 passes,the strength effect of AZ91D-x%Ce （x0.5%） alloys is improved significantly. Among them,the hardness of AZ91D-0.5%Ce alloy is increased about 1 time.

关 键 词：AZ91D镁合金 稀土Ce 等通道转角挤压 维氏硬度 

分 类 号：TG292[金属学及工艺—铸造]