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利用真空熔炼-离心铸造工艺制备出ZCuSn3Zn8Pb6Ni1FeCo合金试样。使用图像分析软件确定了合金的晶粒大小。通过光学显微镜、XRD和拉伸测试等分析手段,研究了离心速度对组织及力学性能的影响。结果表明:随着离心速度的增加,合金的平均晶粒大小先减小后增加,离心速度为200 r/min时,晶粒直径最小为22～31μm。抗拉强度随离心速度的变化趋势与晶粒直径变化相同,并在200 r/min时合金抗拉强度达到最大值380 MPa。离心压力降低了临界晶核形核能,提高了扩散激活能和形核速率。随着压力的提高,晶粒得以细化,但是达到最大值后,压力的增加反而使得晶粒细化程度降低。
ZCuSn3Zn8Pb6Ni1FeCo alloy samples were prepared by vacuum melting-centrifugal casting process. The image analysis software was used to determine the grain size of the alloy. The effects of centrifugal velocity on microstructure and mechanical properties were studied by means of optical microscope, XRD and tensile test. The results show that with the increase of centrifugal velocity, the average grain size of the alloy first decreases and then increases. When the centrifugal velocity is 200 r / min, the average grain size is 22 ~ 31μm. The trend of tensile strength with centrifugal speed is the same as the change of grain diameter, and the maximum tensile strength of alloy reaches 380 MPa at 200 r / min. Centrifugal pressure decreases the nucleation energy of critical nuclei and increases the diffusion activation energy and nucleation rate. With the increase of pressure, the grains can be refined, but when the maximum is reached, the increase of pressure makes the degree of grain refinement decrease.