超声场对GW93合金铸件显微组织与拉伸性能的影响

Effect of Ultrasonic Field on Microstructure and Tensile Properties of GW93 Alloy Castings

对Mg-9Gd-3Y-1.2Zr-0.5Zn(GW93)合金熔体进行了功率(0～2000W)、时间(0～120 s)的超声处理,研究了超声功率和时间对GW93合金显微组织与拉伸性能的影响规律。结果表明:经超声处理后,镁合金α(Mg)和第二相明显细化。随着超声功率和时间的增加,α(Mg)和第二相细化程度先增强后降低,合金的抗拉强度和伸长率均先升高后降低。当功率为1000W、时间60s时,合金的α(Mg)和第二相最细小,晶粒尺寸为15.6μm,合金硬度值为74.58HB,抗拉强度为260MPa,伸长率为14.79%。与未超声处理相比,晶粒尺寸细化了76%,布氏硬度、抗拉强度和伸长率分别提高了47.98%、30%、243.95%。

The Mg-9Gd-3Y-1.2Zr-0.5Zn(GW93)alloy melt was treated by ultrasonic power(0-2000W)and time(0-120s).The effects of ultrasonic power and time on the microstructure and tensile properties of GW93 alloy were investigated.The results show that after ultrasonic treatment,the α(Mg)and the second phase of magnesium alloy are refined obviously.With the increase of the ultrasonic power and time,the degree of refinement of α(Mg)and the second phase increase first and then decrease,and the tensile strength and elongation of the alloy first increase and then decrease.When the power is 1000 W and the time is 60 s,the α(Mg)and the second phase of the alloy are the smallest and the grain size is 15.6μm,the hardness of the alloy is 74.58 HB,the tensile strength is 260 MPa and the elongation is 14.79%.Compared with the unultrasonic treatment,the grain size is refined by 76%,the hardness,tensile strength and elongation are increased by 47.98%,30% and 243.95%,respectively.