熔体温度对超声处理Mg-Zn-Er合金组织和性能的影响

采用高强超声熔体处理法制备Mg-Zn-Er合金,研究了导入超声时熔体温度对合金铸态显微组织和性能的影响。结果表明,在超声处理时间和超声输出功率分别为100s和600W时,随着导入超声时熔体温度的提高,合金的铸态显微组织由粗大的枝晶转变为细小均匀圆整的晶粒,并得到最佳的导入超声熔体温度为718℃。在此温度下导入超声时,制得的Mg-5Zn-2Er合金晶粒最细小圆整、粒径分布最均匀,其室温抗拉强度和伸长率都达到最大值,分别为199.6MPa和11.6%,而合金的高温抗拉强度则为最小值。

Effects of Melt Temperature on Microstructure and Properties of Mg-Zn-Er Alloy with Ultrasonic Treatment

Effects of introducing ultrasonic temperature on microstructure and properties of Mg-Zn-Er alloy prepared by high intensity ultrasonic melt treatment were analyzed. The results indicate that as-cast microstructure of the alloy is converted from coarse dendrite into uniformly distributed fine spheroidized grain with increasing in introducing ultrasonic temperature in condition of ultrasonic time for 100 s and ultrasonic power of 600W, in which an optimized temperature is 718℃. The grain with desirable size and uniform distribution and roundness in Mg-5Zn-2Er alloy treated by ultrasonic at 718℃ can be observed, and tensile strength and elongation reach 199.6MPa and 11.6% at room temperature, respectively, exhibiting the maximum value, while tensile strength exhibits the minimum values at high temperature.