Sn对AZ80合金电磁半连续铸造坯料凝固质量的影响

Effect of Sn on Solidification Quality of AZ80 Billets Cast by Electromagnetic Semi-Continuous Casting

采用电磁半连续铸造工艺,利用探伤技术结合坯料的组织分析,研究了Sn对AZ80合金坯料凝固质量的影响,探讨了合金组织的演变及对凝固质量的改善。结果表明:随着Sn含量的增加,合金组织逐渐细化,缩孔形成趋势降低,金属间化合物及夹杂物偏聚程度减小,且分布趋于均匀。结合熔体精炼中适当提高净化温度和延长净化时间并采用陶瓷过滤装置,可有效降低熔体中夹杂物的残留量,改善合金坯料的凝固质量。

The billets of AZ80 alloy containing Sn were cast by electromagnetic semi-continuous casting. The effect of Sn content on the solidification quality of the AZ80 billets was studied by means of chemical composition analysis, X-ray analysis, scanning electron microscope observation, etc. The macrostructure evolution of the alloy and the improvement of the solidification quality were analyzed. The results show that the addition of Sn element to AZ80 alloy, can refine the grain structure of the alloy, decrease the tendency to shrinkage formation, and the segregation degree of intermetallic compounds and inclusions in the alloys. Hence, their distribution is nearly uniform. Moreover, the residual inclusions in the melt could be effectively reduced by increasing the refining temperature and time and by using the ceramic filtration system.