Al-10Sr和Al-5Ti-0.2C对ZL101合金组织的影响

Effects of Al-10Sr and Al-5Ti-0.2C on Microstructure of ZL101 Alloy

在ZL10 1合金熔体中分别或同时添加不同量的Al 10Sr和Al 5Ti 0 .2C ,保温不同时间 ,利用光学显微镜和电镜扫描 ,研究了Al 10Sr ,Al 5Ti 0 .2C对ZL10 1合金组织的影响规律。试验结果表明 ,向ZL10 1合金中添加质量分数为 0 .5 %的Al 10Sr ,可使共晶Si从粗大的针、片状转变为细小的短纤维状 ,同时促进了α Al枝晶的形核生长 ,晶粒尺寸在 10 0～ 2 5 0 μm之间。若添加质量分数为 0 .2 %的Al 5Ti 0 .2C ,可使初生α Al晶粒成为 40～ 70 μm的等轴晶 ,对共晶Si也有一定的变质作用。当同时加入Al 10Sr和Al 5Ti 0 .2C时 ,α Al枝晶和共晶Si同时得到细化和变质 ,这主要归功于Al 10Sr和Al 5Ti 0 .2C对ZL10 1合金细化变质的交互作用。

The effects of varying quantity of Al-10Sr and Al-5Ti- 0.2Cwith separate or simultaneous addition on the microstructure of ZL101 alloy at different holding time were examined by means of OM and SEM. The results showed that 0.5% addition of Al-10Sr to the alloy leads from coarse needle-like or flake-like eutectic Si morphology to fine short fibrous one and prompts the nucleation and growth of the dendritic α-Al phase with grain size varying between 100 and 250 μm. 0.2% addition of Al-5Ti-0.2C also can modify eutectic Si to some extent and generate equiaxed primary α-Al phase with about 40～70 μm. Simultaneous addition of both Al-10Sr and Al-5Ti-0.2C can refine and modify both α-Al phase and eutectic Si, which is attributed to the interactive effect of refinement and modification of Al-10Sr and Al-5Ti-0.2C.