【摘要】 以Sn-3.8Ag-0.7Cu钎料为对象,研究熔体结构转变和稀土元素Ce的添加对钎料性能的影响。研究发现Sn-3.8Ag-0.7Cu-xCe存在温度诱导的液-液结构转变,且经过熔体过热处理的钎料凝固组织较为细化,组织分布更加均匀,钎料的润湿性能和接头的剪切强度也得到提高;同时熔体结构转变还能够改善焊后界面IMC的形态。Ce的添加对钎料凝固组织有一定的影响,当Ce的质量分数大于0.2%时,随着Ce含量的增加,组织逐渐变得粗大、不均匀;另外,随着Ce含量的增加,钎料的润湿性能和接头剪切强度均呈先增加后降低的趋势,在试验范围内,当Ce的质量分数为0.2%时,钎料的润湿性能最佳,接头剪切强度最高。熔体结构转变和微量的Ce的添加均可以改善Sn-3.8Ag-0.7Cu钎料的性能。更多还原

【Abstract】 The effects of melt structure transformation and Ce addition on properties of Sn-3.8Ag-0.7Cu-xCe solder were investigated.The results show that there exists a temperature-induced liquid-liquid structure transformation in Sn-3.8Ag-0.7Cu-xCe solder melt,and the solidification microstructure of solder becomes refined and distributes more uniformly after overheating processing.Wetting Properties of solder and the shear strength of soldered joint has also been improved.At the same time,the melt structure transition could improve the form of interface IMC in soldered joint.The addition of rare earth element Ce has an influence on the solidification structure of solder.Wetting properties of solder and the shear strength of welding joint increase first and then decrease with Ce increasing.When Ce addition is 0.2%(mass fraction),the wet ability of solder is the best,and the shear strength of soldered joint is the highest.Overall,melt structure transformation and the trace addition of Ce could improve the performance of Sn-3.8Ag-0.7Cu solder,and 0.2%Ce(mass fraction)addition is preferred.更多还原