부산대학교 도서관

The shrinkage porosity of a Mg–6Gd–3Y–0.5Zr (wt%) alloy was reduced by hot isostatic pressing (HIP) in our previously reported study. However, regions of severe shrinkage porosity (large areas of interconnected shrinkage porosity) were still not compact after the HIP process. In this study, three kinds of magnesium alloys were investigated to evaluate the applicability of HIP for magnesium alloys with contents of varying shrinkage porosity and alloying elements. The results show that HIP is confirmed to be ineffective for alloys with regions of severe shrinkage porosity, which can be detected by radiography. In contrast, the tensile properties and consistency were enhanced by HIP in alloys that had nominal compact regions that appeared to be free of shrinkage porosity according to radiography but actually contained a small area of interconnected shrinkage porosity. This enhancement mainly results from shrinkage porosity closure. On the other hand, variations in alloying elements had a negligible influence on shrinkage porosity closure during the HIP process. The initial contents with shrinkage porosity are believed to be the key determining factor for the effectiveness of HIP for Mg alloys. This work illustrates the potential application of HIP to Mg alloys to further improve and ensure the consistency of mechanical properties in nominal compact castings. [ABSTRACT FROM AUTHOR]