Transactions of Materials and Heat Treatment

Title：Influence of strain on microstructure and mechanical properties for forged Mg-Gd-Y-Zn-Zr alloy

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ClassificationCode：TG146.22

year,vol(issue):pagenumber：2019,44(4):145-150

Abstract：

Two Mg-Gd-Y-Zn-Zr samples with strain of 1.5 and 2.1 were successfully fabricated by multi-direction forging process, and the influences of different strains on the microstructure and mechanical properties of forging samples were investigated by the optical microscopy, scanning electron microscopy, XRD macrotexture measurement and mechanical property test. The results show that with the increasing of strain from 1.5 to 2.1, the microstructure in different regions of sample is refined to a large extent due to the increase of recrystallization volume fraction. However, the average size of recrystallization grains in such microstructure is kept around 2.6 μm independent of strain and region of sample. Furthermore, the central part of sample with strain of 2.1 occupies the highest comprehensive mechanical properties with the yield strength of 263 MPa, the tensile strength of 346 MPa and the elongation of 18.6%, respectively, and its remarkable mechanical properties can be ascribed to the comprehensive effect of grain refinement and random crystal orientation resulted from the high strain.

Funds：

国家自然科学基金资助项目（51574291）；中南大学研究生自主探索创新项目(2018zzts485)

刘运峰（1992-），男，硕士研究生 E-mail：15673109789@163.com 通讯作者：刘楚明（1960-），博士，教授，博士生导师 E-mail：cmliu803@sina.com

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