超声处理对医用Mg-Zn合金组织、力学性能和生物腐蚀行为的影响

Effects of ultrasonic treatment on microstructure,mechanical properties and corrosion behavior of Mg-Zn alloy

在医用Mg-7Zn合金的凝固过程中施加超声处理,研究了超声功率对合金凝固组织、力学性能及生物腐蚀行为的影响。结果表明,超声处理能够显著细化合金的凝固组织。随着超声功率的增加,合金中的初生α-Mg相的晶粒尺寸逐渐减小,MgZn相由不连续网状和颗粒状共存逐渐向孤岛状和颗粒状共存转变,其体积分数也逐渐降低。随着超声功率的增加,合金的力学性能逐渐提升,当超声功率增大到900 W时,合金的抗拉强度和伸长率相比未处理合金分别提高了48.5%和43.5%。随着超声功率的增加,试样在Hank’s溶液中的析氢速率和腐蚀质量损失速率均逐渐降低,表明合金的耐腐蚀性能逐渐提高。

The effects of ultrasonic treatment on solidification microstructure,mechanical properties and biological corrosion behavior of Mg-7Zn alloy were studied.The results show that the ultrasonic treatment can significantly refine the solidification structure of the alloy.With the increase of ultrasonic power,the grain size of the primaryα-Mg phase in the alloy gradually decreases.The MgZn phase gradually changes from discontinuous reticular and granular coexistence to island-like and granular coexistence,and its volume fraction also gradually decreases.With the increase of ultrasonic power,the mechanical properties of the alloy are gradually improved.When the ultrasonic power increases to 900 W,the tensile strength and the elongation of the alloy increase by 48.5%and 43.5%compared with the untreated alloy,respectively.With the increase of ultrasonic power,the hydrogen evolution rate and corrosion mass loss rate of the sample in hank's solution gradually decrease,indicating that the corrosion resistance of the alloy is gradually improved.