摘要
用金相显微镜、能量色散谱仪(EDS)和X射线衍射仪(XRD)研究了稀土元素Ce对AZ91D镁合金铸态组织的影响。结果表明,Ce对AZ91D镁合金具有明显的变质效果,加入0.4%Ce后,α-Mg树枝晶变化不明显,晶界上的β-Mg17Al12相呈断续网状分布;加入0.8%Ce后,合金晶界上的离异共晶β相基本上断裂成骨骼状,转变为颗粒状且分布比较均匀;加入1.2%稀土Ce后,枝晶变细,共晶β相完全变为颗粒相,弥散分布于晶界处。微结构分析发现,组织中出现了分布于晶界处的杆状Al10Ce2Mn7化合物。
The effects of rare-earth Ce on microstructure of AZ91D alloy were studied.The results indicate that the microstructure was fined effectively by the Ce addition.When adding 0.4%Ce,the dendrite formation of α-Mg doesn＇t change obviously, the β-Mg17Al12 on the boundary presents itself discontinuous net;After adding 0.8%Ce, most of the β-Mg17Al12 was divorced to the skeleton mutually, changing into the uniform granular structure;After adding 1.2%Ce,the dendrite formation of α-Mg turns fine,the all of β-Mg17TAl12 changes into granular structure which is distributed dispereedly on the boundary.The analysis by using SEM shows that the needle compounds of Al10Ce2Mn7 are distributed on the boundary.
出处
《稀有金属快报》
CSCD
2006年第2期31-35,共5页
Rare Metals Letters
