超声处理功率对Mg-6Zn-0.5Y合金显微组织及力学性能的影响

Effect of applied ultrasonic power on microstructure and mechanical properties of Mg-6Zn-0. 5Y magnesium alloy

对Mg-6Zn-0.5Y合金熔体进行功率分别为0,300,600,900 W连续超声处理。通过金相显微镜、X射线衍射仪、扫描电镜等分析手段研究了超声处理功率对其显微组织及力学性能的影响。结果表明,经600 W超声处理的Mg-6Zn-0.5Y合金组织细化效果最好,初生α-Mg相由粗大的树枝晶变为细小的球状等轴晶,准晶I相由粗大的半连续网状分布变成断续的细线状分布。此外,力学性能分析显示,当超声处理功率为600 W时,Mg-6Zn-0.5Y合金的抗拉强度和伸长率均达到最大值,比未处理时分别提高了67%和56%。

Continuous ultrasonic treatment was introduced into the solidification of the Mg-6Zn-0.5Y magnesium alloy with the power of 0,300,600,900 W,respectively.The effect of ultrasonic power on microstructure and mechanical properties of Mg-6Zn-0.5Y magnesium alloy were investigated through micrograph,X-ray diffraction analysis （XRD）and scanning electron microscope （SEM）.The results showed that with the application of 600 W ultrasonic treatment,the primary α-Mg phases were transformed from coarse dendrites to fine equiaxed grains,and the semicontinuous quasicrystalline phases at α-Mg boundaries were modified into discontinuous. Besides,the Mg-6Zn-0.5Y magnesium alloy prepared with 600 W ultrasonic treatment exhibited the best ultimate tensile strength and elongation.Compared to the untreated alloy,the ultimate tensile strength and elongation are improved by 67%,56%,respectively.