医用Zn-1.5Mg合金的组织与性能研究

研究了医用Zn-1.5Mg合金的微观组织变化,探讨了其对力学性能的影响.对铸态、均匀化处理和轧制态Zn-1.5Mg合金的微观组织进行了表征,分析了合金的相组成.选取变形量为49%和73%的轧制态Zn-1.5Mg合金,在模拟体液中分别浸泡1、2、4、8、14、22、32天,统计了腐蚀速率的变化.结果表明:铸态Zn-1.5Mg合金的相组成主要为η-Zn相、Mg_2Zn_(11)相和MgZn_2相,均匀化处理后MgZn_2相消失.铸态Zn-1.5Mg合金均匀化后共晶组织的片层状形貌消失,显微组织变得更加均匀.经总压下量73%轧制变形后,枝晶细化.轧制后的浸泡实验显示,样品浸泡4天后腐蚀速率基本保持在0.2 mm/a左右,电化学实验显示两种轧态试样腐蚀电压在-0.9 V左右.

Microstructure and properties of biodegradable Zn-1.5Mg alloy

The phase selection and microstructure evolution of the biodegradable Zn-1.5Mg alloy were studied. The microstructures as cast condition, after homogenization treatment and in the rolling state of Zn-1.5Mg alloy were characterized,taken the Zn -1.5Mg rolling alloys of the deformation radios being 49%, 73% immersed in the simulated body fluid(SBF) for 1,2,4,8,14,22,32 days, the corrosion rate data were recorded. The results showed that the phase composition of Zn-1.5Mg alloy under as cast condition is mainly η-Zn phase, Mg2Zn11phase and MgZn2,MgZn2phase disappears after homogenization. As the as - cast Zn -1.5Mg alloy is homogenized, the lamellar morphology of the eutectic structure disappears and the microstructure becomes more uniform. Through the rolling deformation of the total reduction being of greater than 73%,the dendrites are refined. The results showed that the corrosion voltage of the two kinds of rolling samples is about -0.9 V,is about 0.2 mm/a.