纳米TiO2颗粒对SnAgCu钎料组织与性能的影响

Effect of Nano-particles TiO2 on the Microstructures and Properties of SnAgCu Solders

摘要:

研究了纳米TiO2颗粒对SnAgCu钎料组织和性能的影响。结果表明：微量的纳米TiO2颗粒可以增加SnAgCu钎料的润湿铺展面积，显著提高SnAgCu焊点的拉伸力和剪切力。添加过量时焊点的力学性能会有一定程度的下降。经过优化分析发现，纳米TiO2颗粒的最佳添加量为0.1%(质量分数, 下同)。SnAgCu-0.1TiO2相对SnAgCu钎料基体组织得到明显的细化，树枝晶的间距下降62.5%。 经过热循环测试，发现0.1%TiO2可以显著提高SnAgCu焊点的抗热疲劳特性。主要归因于纳米颗粒对位错的钉扎作用，因而阻止了裂纹在钎料基体内部的扩展

Abstract:

The effect of nano-particles TiO2 on the microstructures and properties of SnAgCu solders was investigated. The results indicate that adding a small amount of nano-particles TiO2 can improve the wettability of SnAgCu solders, and the mechanical properties of solder joints can be enhanced significantly; however, excessive nano-particles would reduce the properties. It can be found that the optimum content of nano-particles is 0.1 wt% for SnAgCu solders, when the matrix microstructure of solders may be refined obviously, and the dendrite-arm spacing of SnAgCu solders is decreased by 62.5% after soldering. Moreover, during thermal cycling tests, the SnAgCu solder joints show superior thermal fatigue resistance with the addition of 0.1wt% TiO2 because the particles restrict the movement of dislocations, thus hindering the propagation of cracks in matrix microstructure.