Microstructure, texture characteristics, mechanical and bio-corrosion properties of high strain rate rolled Mg-Zn-Sr alloy
Microstructure, texture characteristics, mechanical and bio-corrosion properties of high strain rate rolled Mg-Zn-Sr alloy
复制标题
高应变率轧制Mg-Zn-Sr合金的显微组织、织构特征、力学和生物腐蚀性能
DOI：
10.1007/s12540-019-00601-y
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发表时间：
--
影响因子：
3.5
通讯作者：
Cheng Meixin
中科院分区：
文献类型：
--
作者：
Yan Hongge;Gong Xiaole;Chen Jihua;Cheng Meixin
研究了高应变速率轧制Mg-5 Zn-xSr合金（x = 0，0.2，0.6，1.0）的显微组织、织构特征、力学性能和生物腐蚀性能。低含量Sr的加入促进了Mg-5 Zn合金中纳米MgZn 2的动态析出，其中0.6%Sr的效果最好。这些高密度的MgZn 2颗粒可以钉扎动态再结晶晶粒的晶界，抑制其长大。低含量的Sr（≤ 0.6%）增强了（0002）基面织构，而1.0%Sr则相反。轧制态Mg-5 Zn-0.6Sr合金具有最佳的抗拉强度（359 MPa）和断裂伸长率（20%）组合。高强度可归因于减小的晶粒尺寸、沉淀和基底织构强化。Mg-5 Zn-xSr合金具有优良的耐生物腐蚀性能，但由于晶粒尺寸、动态再结晶度、动态析出相和织构特性的综合作用，少量Sr的加入并不能进一步提高合金的耐生物腐蚀性能。添加0.6%Sr可在不牺牲抗生物腐蚀性能的前提下，显著提高合金的强度。
AbstractMicrostructure, texture characteristics, mechanical and bio-corrosion properties of the Mg–5Zn–xSr alloys (x = 0, 0.2, 0.6, 1.0) prepared by high strain rate rolling are carefully studied. A low level of Sr addition enhances dynamic precipitation of nano-scale MgZn2particles in the as-rolled Mg–5Zn alloy, with 0.6%Sr showing the maximum efficiency. These high-density MgZn2particles can pin grain boundaries of dynamic recrystallization grains and inhibit their growth. A low level of Sr addition (≤ 0.6%) enhances the (0002) basal texture, but 1.0%Sr is just the reverse. The as-rolled Mg–5Zn–0.6Sr alloy exhibits the best combination of ultimate tensile strength (359 MPa) and elongation to rupture (20%). The high strength can be attributable to a reduced grain size, precipitation and basal texture strengthening. The Mg–5Zn–xSr alloys exhibit excellent bio-corrosion resistance, but a minor Sr addition cannot bring about further bio-corrosion resistance improvement due to the multiple actions of grain size, DRX degree, dynamic precipitates and texture characteristics. The 0.6%Sr addition can greatly improve the strength of the as-rolled alloy at no expense of bio-corrosion resistance.Graphic Abstract