摘要
对含Sr(0.05%~0.6%)AZ91铸态镁合金组织进行了观察,并且采用'边-边匹配'模型研究了其细化机制。结果表明,微量Sr对AZ91铸态组织有明显的晶粒细化效果,Sr含量为0.05%时细化效果最为显著。通过'边-边匹配'模型计算,得到[021]Al4Sr∥[1-1 0]Mg17Al12,(200)Al4Sr∥(332)Mg17Al12,表明微量Sr对AZ91镁合金铸态晶粒细化主要是Al4Sr相为Mg17Al12相的形成提供有效的异质形核核心,从而加速Mg17Al12相对α-Mg枝晶长大的阻碍作用。
As-cast microstructure and grain refinement in the AZ9 1 magnesium alloys with different Sr contents （0,0.05%,0.1%,0.3% and 0.6wt%）were observed in this paper,and the grain refining mechanism was an-alyzed by using the calculation of “edge-to-edge”matching model.The results indicated that adding trace Sr to as-cast AZ91 alloy had obviously effects on grain refinement,thereinto with the addition of 0.05% Sr was the most remarkable.In addition,the [021]Al4Sr∥[1-1 0]Mg17 Al12 and （200）Al4Sr∥（332）Mg17 Al12 were calculated by u-sing “edge-to-edge”matching model,which can provide an evidence that the Al4 Sr phase was the effective het-erogeneous nucleant for the Mg17 Al12 phase probably.However,the mechanism of grain refinement of trace Sr effect on the as-cast microstructure of AZ9 1 magnesium alloy was the Al4 Sr phase provide heterogeneous nucle-ant for the Mg17 Al12 phase that accelerating the formation of Mg17 Al12 phase and then restricted the growth of α-Mg .
出处
《功能材料》
EI
CAS
CSCD
北大核心
2014年第2期63-67,共5页
Journal of Functional Materials
基金
科技部国际合作资助项目(2008DFR50040)
国家自然科学基金资助项目(50725413)
重庆科学技术委员会资助项目(CSTC,2011ggB50013,2011jjA50019,2011AC4119)
重庆市教委资助项目(KJ120834)
重庆大学研究生创新基金资助项目(CDJZR11130024)
