摘要
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 was prepared by using vacuum melting and centrifugal casting technology.Grain size of the alloy was determined by a image analysis software.The effect of centrifugal velocity on microstructure and mechanical properties of the alloy were investigated by optical microscope,XRD and tensile test.The results show that with increase of centrifugal velocity the average grain size decreases first and then increases,and it reaches the minimum value of 22-31 μm at the centrifugal velocity of 200 r /min.The same changing trend of tensile strength is observed and the maximum tensile strength of 380 MPa is obtained for the alloy fabricated at the centrifugal velocity of 200 r /min.The centrifugal pressure lowers down the critical nucleation energy,raises the diffusion activation energy and nucleation rate.With the increasing of the pressure,the grain size is refinement,however,after it reaches the minimum value then increases with the pressure increasing.
出处
《材料热处理学报》
EI
CAS
CSCD
北大核心
2010年第7期83-87,共5页
Transactions of Materials and Heat Treatment
基金
国家重点基础研究发展(973)计划资助项目(2006CB605200)
关键词
离心压力
金属凝固
形核速率
centrifugal pressure
metal solidification
nucleation rate
