熔体过热对Al-18%Si合金中初生硅形态的影响

Effect of Melt Superheating on Morphology of Primary Siliconin Al-18%Si Alloys

对Al-18%Si合金进行熔体过热处理,然后研究熔体过热温度及保温时间对合金中初生硅形态的影响,并利用光学显微镜观察组织,用ImagePro金相分析软件测定初生硅的平均直径。研究结果表明,熔体过热处理后的Al-18%Si合金中初生硅会发生显著细化,并以细小块状均匀分布。熔体过热处理温度越高,初生硅的平均尺寸也会越小,同时熔体过热需要一定的保温时间以保证初生硅分布均匀。

The melt superheat treatment of Al-18%Si alloy was carried out.The influence of melt superheat temperature and holding time on the morphology of primary silicon in the alloy was studied.The tissue was observed with an optical microscope and the aver⁃age diameter of primary silicon was measured with Image Pro metallographic analysis software.The results show that the primary sili⁃con in the Al-18%Si alloy after the melt superheat treatment will be significantly refined and distributed uniformly in small chunks.The higher the melt superheat treatment temperature is,the smaller the average size of the primary silicon will be.At the same time,the melt superheat needs a certain amount of holding time to make the primary silicon evenly distributed.