Ag和Ni颗粒对63Sn37Pb力学性能和润湿性能的影响
Effect of Ag and Ni particles on mechanical properties and wettability of SnPb composite solder
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摘要: 锡铅钎料在电子工业中广泛应用。锡铅共晶或近共晶钎料熔点较低,钎焊工艺性能好,但抗蠕变性能差。作者运用弥散强化原理,分别选用1 μm的Ag颗粒和Ni颗粒作为增强体,以63Sn37Pb为基体,制成金属颗粒增强的锡铅基复合钎料。在再流焊条件下,弥散分布的增强体与基体冶金结合,在增强体的表层形成一薄层金属间化合物,蠕变性能大幅度提高。试验证明,在相同条件下,与基体钎料63Sn37Pb相比,铺展面积略微下降,但Ag颗粒体积百分数为5%和10%的颗粒增强的锡铅基复合钎料的蠕变寿命分别提高8倍和6倍,同时抗拉强度和剪切强度均得到提高;Ni颗粒增强的复合钎料的蠕变寿命大幅度提高,Ni颗粒体积百分数为5%和10%的颗粒增强的锡铅基复合钎料的蠕变寿命分别提高了85倍和186倍,但润湿性能、剪切强度和延伸率均明显降低。Abstract: Solder is widely used in electronic industry, which has a lower melting point, good solderability and good mechanical properties. However, its creep resistance is bad. In the present work, Ag and Ni particles with size of about 1 μm are added in the eutectic 63Sn-37Pb solder to form metal particles enhanced SnPb composite solders. Under re-flow soldering the enhanced particles are uniformly dispersed in the 63Sn37Pb alloy, and intermetallic compounds with very thin layer was formed between the enhanced particles and matrix. Tight metallurgical coalescence is realized. So the creep rupture life of the composite solders are improved distinctly. At ambient temperature the creep rupture life of 5vol% and 10vol%Ag particles enhanced SnPb composite solder joints can be increased by 8 times and 6 times compared to the ordinary 63Sn-37Pb solder. At the same time, tensile strength and tensile-shear strength of Ag particles enhanced composite solders were higher, and lower elongation and spreading areas than those of 63Sn37Pb solder. At the same condition, the rupture life of Ni particles enhanced composite solders is improved evidently. Those of 5vol% and 10vol% Ni particles enhanced SnPb composite solder joints can be increased by 85 times and 186 times compared to the ordinary 63Sn-37Pb solder. However, solderability, tensile-shear strength and elongation of Ni particles enhanced composite solders were lower than those of 63Sn37Pb solder.