摘要
The solidification characterization of Mg-xZn-0.5Zr(x=0,1,3,4,5 wt%)alloys has been extensively investigated through thermal analysis,microstructure characterization and thermodynamic calculations.The impact of Zn content on the grain growth restriction,dendrite coherency and thus the final grain size has been investigated and discussed.Increasing Zn content,the grain size of Mg-xZn-0.5Zr alloy was firstly refined and then coarsened with the finest grain size of^50μm for the Mg-3 Zn-0.5 Zr(ZK31)alloy.Significant effects of the grain size on the mechanical properties were observed in the investigated alloys.The combination of growth restriction factor theory and dendrite coherency point provides a reasonable explanation of the grain size results.It helps to further understand the mechanisms of grain refinement and grain coarsening related to solute content,providing reference for alloy design and grain size prediction.
基金
supports by the National Key Research and Development Program of China(No.2017YFB0702001)
the Natrual Science Foundation of China(No.51621063)
the support from the International Joint Laboratory for Micro/Nano Manufacturing and Measurement Technologies,the Collaborative Innovation Center of High-End Manufacturing Equipment and the Science and Technology Department of Shaanxi Province(Nos.2016KTZDGY-04-03 and 2016KTZDGY-04-04)
the National Natural Science Foundation for Young Scholars(No.51701218)
the National Science and Technology Major Project of China through Project No.2017ZX04014001。
