微量元素Ce/Sb及时效处理对AZ91D合金显微组织及力学性能的影响  

Effect of Trace Ce/Sb and Aging Treatment on Microstructure and Mechanical Properties of AZ91D

作　　者：周宁[1] 林晓娉[1] 范学义[1] 李贝[1] 张丽娟[1] 

机构地区：[1]河北工业大学材料科学与工程学院,天津300130

出　　处：《铸造》2009年第1期57-59,共3页Foundry

摘　　要：研究了时效处理对添加Ce/Sb的AZ91D合金显微组织、力学性能的影响。结果表明,添加Ce和Sb后,β-Mg17Al12变为断续网状或粒状分布,数量也相对减少,并形成弥散分布的Mg3Sb2、CeSb、Al11Ce3新相。时效处理后,试验合金晶界变得模糊,随时效过程进行,新相逐渐析出,最终在时效处理为200℃×12h时形成稳定的颗粒状或短棒状析出相;220℃×12h时效处理后,析出相已经开始聚集、长大,成为条状相。时效处理后,合金维氏硬度提高,在220℃×12h时,维氏硬度达HV97,同比铸态提高37%。The effects of aging treatment on microstructure and mechanical properties of AZ91D alloy with Ce/Sb were studied. The results showed that after adding Ce and Sb, 15-Mg17Al12 phase changed to intermittent network or granular distribution in a reduced number, and the dispersively distributed new phases of the Mg3Sb2, CeSb and Al11Ce3 formed. After aging treatment, the grain boundaries of the test alloy become blurred, new phases precipitate gradually with the aging process, and finally become a stable short rod or granular precipitates after aging treatment for 200 ℃×12 h; the precipitates has begun gathering, then grew up and become a strip phase after aging treatment for 220℃×12 h, meanwhile, the Vickers hardness of the as-cast alloy is improved to HV97, which is increased by 37% compared with that without aging treatment.

关 键 词：AZ91D 时效处理 组织细化 

分 类 号：TG156.92[金属学及工艺—热处理]