Ni元素对SnCu无铅焊料性能的影响.doc

摘 要 随着科学技术的迅猛发展，人类对于经济效益和生态环保的要求不断增强，由于传统的锡铅焊料会对环境和人类身体健康造成危害，所以在电子封装产业中无铅焊料的发展势在必行，Sn-Cu系无铅焊料不仅成本低廉，而且综合性能良好，成为传统锡铅焊料的优良替代品，有着很大的研究价值和发展潜力。 本文旨在研究添加不同Ni元素对Sn-Cu系无铅焊料性能的影响，在Sn-0.7Cu无铅焊料中添加不同含量的Ni元素，设计焊料合金成分配比，熔炼试样，制备金相试样，并进行金相组织观察和性能测试，包括显微硬度、熔化特性以及XRD物相分析和电子探针成分分析。通过分析以上实验结果探究不同Ni元素的添加对Sn-Cu系无铅焊料显微组织、硬度、熔化特性等的影响，得到结论如下： （1）、Sn-0.7Cu合金中添加Ni元素后，产生的（Cu.Ni）6Sn5可以成功地抑制Sn-Cu系无铅焊料中Cu6Sn5金属间化合物中的龟裂，使得组织更加均匀。 （2）、Sn-0.7Cu合金中添加Ni元素后，组织形貌发生了明显的变化。组织中的（Cu.Ni）6Sn5相随着Ni元素含量的增多，逐渐增大且均匀化。 （3）、Sn-0.7Cu合金中添加Ni后，焊料合金熔点略有上升，但是熔程较小，有利于焊接；焊料合硬度先下降再升高，其中Sn-0.7Cu-0.6Ni合金的硬度最低。 关键词：无铅焊料，Sn-0.7Cu，显微硬度，焊接性能 Abstract The economic and environmental awareness of human beings is growing with the rapid development of science and technology. the traditional tin-lead solder is harm to environment and our health, So lead-free solder is imperative in the electronics packaging industry. Sn-Cu lead-free solder is not only inexpensive, but also has good properties which may act as an alternative to traditional tin-lead solder.this research has great meaning and development value. This paper aims to study the influence on different Ni to Sn-Cu lead-free solder. We add different content of Ni element to Sn-0.7Cu lead-free solder , by the designing the composition of the solder , using the melting metallographic technology to make the metallographic sample. Then, observe the microstructure and properties of the sample. These properties including micro-hardness, melting characteristics.In addition,we should carry on the XRD phase analysis and electron probe microanalysis. By analyzing the results of the above experiment to recognize the influence on different Ni to Sn-Cu lead-free solder. Including the microstructure, hardness, melting characteristics of the Sn-Cu lead-free solder. The conclusions are as follow: 、The emerge of （Cu.Ni）6Sn5 by adding Ni to Sn-0.7Cu alloy reduced the split of the Cu6Sn5 which makes organization more pure. 、The microstructure has significant changes by adding Ni to Sn-0.7Cu a