交流磁场对Mg-Gd-Y-Zr合金组织和力学性能的影响

Effects of AC Magnetic Field on Structure and Mechanical Properties of Mg-Gd-Y-Zr Alloy

利用OM、SEM及万能拉伸试验机等测试手段,探究了不同参数的连续交流磁场和间断交流磁场对Mg-6Gd-3Y-0.6Zr合金凝固组织和力学性能的影响。结果表明,连续和间断交流磁场均可细化Mg-6Gd-3Y-0.6Zr合金的晶粒尺寸并提高其力学性能;两种磁场处理合金的晶粒尺寸无明显差别,但间断交流磁场处理后合金的力学性能比连续交流磁场处理后的低。连续交流磁场处理条件下,在200~600℃内,随着模具预热温度升高,合金晶粒尺寸逐渐减小;在0~300 V范围内,随着交流电压增加,合金晶粒尺寸先减小后增大,转折点为250 V。间断交流磁场处理条件下,当放电频率在1~10 Hz内或占空比在10%~40%内,随着放电频率或占空比提高,合金晶粒尺寸先减小后增大,转折点分别为5 Hz和20%。

Using OM,SEM,universal tensile testing machine and other testing methods,effects of continuous AC magnetic field and intermittent AC magnetic field with different parameters on solidification structure and mechanical properties of Mg-6 Gd-3 Y-0.6 Zr alloy were explored.The results indicate that both continuous AC magnetic field and intermittent AC magnetic field can refine grains of Mg-6 Gd-3 Y-0.6 Zr alloy and improve its mechanical properties effectively.There is no significant difference in grain size of the alloy under the two different magnetic field treatment conditions,however mechanical properties of the alloy with intermittent AC magnetic field treatment is lower than those of ones with continuous AC magnetic field treatment.Under the condition of continuous AC magnetic field,in the range of 200~600 ℃,with the increase of mold preheating temperature,grain size of the alloy is decreased gradually.In the range of 0~300 V,with the increase of AC voltage,grain size of the alloy is decreased at first and then increased,and the turning point is 250 V.Under the condition of intermittent AC magnetic field,when the discharge frequency is 1~10 Hz or the duty cycle is 10%~40%,as the discharge frequency or duty cycle increases,grain size of the alloy is decreased at first and then increased,where the turning point is 5 Hz or 20%,respectively.