Influence of Zn addition on the microstructure, tensile properties and work-hardening behavior of Mg-1Gd alloy
Influence of Zn addition on the microstructure, tensile properties and work-hardening behavior of Mg-1Gd alloy
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Zn添加对Mg-1Gd合金显微组织、拉伸性能及加工硬化行为的影响
DOI：
10.1016/j.msea.2019.138779
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发表时间：
2020
期刊：
影响因子：
6.4
通讯作者：
Pan Fusheng
中科院分区：
文献类型：
--
作者：
Zhao Jun;Jiang Bin;Yuan Yuan;Tang Aitao;Sheng Haoran;Yang Tianhao;Huang Guangsheng;Zhang Dingfei;Pan Fusheng
研究了挤压Mg-1Gd-xZn （x= 0、0.5、1.0、1.5、wt.%）合金板材的组织、拉伸性能和加工硬化行为。所有挤压薄片都表现出完全再结晶的微观结构和弱的挤压方向（ED）分裂织构。当Zn含量增加到1.0 wt%时，Mg-1Gd片材的平均晶粒尺寸略有减小，而Mg-1Gd-1.5Zn片材的晶粒尺寸急剧减小，这主要是由于存在大量的w相细相析出。锌的加入导致了弱的ed -劈裂织构，并逐渐形成新的横向（TD）劈裂织构成分。Zn溶质、w相细相析出和添加Zn导致的织构弱化共同提高了Mg-1Gd-xZn片材的强度和延展性。然而，过量的Zn会导致Mg5Gd析出，从而降低塑性。随着Zn含量从0 wt%增加到1.5 wt%， Mg-1Gd-xZn板材的加工硬化指数沿ED方向由0.34逐渐增大到0.39，沿TD方向由0.23逐渐增大到0.29。同时，沿ED和TD的硬化能力分别从1.73和0.73增加到1.84和1.07。
Microstructures, tensile properties and work-hardening behavior of extruded Mg-1Gd-xZn (x= 0, 0.5, 1.0, 1.5, wt.%) alloy sheets were investigated in the present work. All the extruded sheets exhibit a fully-recrystallized microstructure and a weak extrusion-direction (ED)-split texture. The average grain sizes of Mg-1Gd sheets slightly decrease with the increase of Zn content up to 1.0 wt%, while a sharp decrease of the grain size occurs in Mg-1Gd-1.5Zn sheet attributed to the existence of abundant fine W-phase precipitates. Zn addition is found to cause a weak ED-split texture and to gradually form new transverse direction (TD)-split texture component. The combination of Zn solute, fine W-phase precipitate and weakening texture induced by Zn addition simultaneously improve the strengths and ductility of Mg-1Gd-xZn sheets. However, excessive Zn addition leads to larger Mg5Gd precipitates and thus decreases the ductility. With the increment of Zn content from 0 to 1.5 wt%, work-hardening exponents of Mg-1Gd-xZn sheets gradually increase from 0.34 to 0.39 along ED, and from 0.23 to 0.29 along TD, respectively. Meanwhile, hardening capacities increase from 1.73 to 1.84 along ED, and from 0.73 to 1.07 along TD, respectively.