Abstract

Lead cannot be used in the solder material anymore due to environmental legislations which is related to the inherent toxicity of lead. This paper investigates the effect of silver (Ag) addition on the melting behavior, microstructure, and microhardness of Ternary lead free solder alloy Sn–0.5Cu–3Bi. The contact angle between Sn–0.5Cu–3Bi and Cu-substrate were also analyzed. Samples with different Ag percentages (0, 0.25, 0.5, 0.75 and 1.0 wt%) in Sn–0.5Cu–3Bi were prepared using an induction furnace, annealing furnace with argon gas. Tests were conducted for melting temperature using TG–DTA analysis, chemical composition using ICP–OES, Hardness using Vickers’s hardness tester and the microstructure using Field emission scanning electron microscopy. The obtained results were thoroughly analyzed. The results show that the Ag addition has striking positive effects on enhancing the properties of the base solder alloy. Melting point is found to be decreasing with the increase in Ag content. Hardness and contact angle were improved with the addition of Ag. The microstructure observations revealed that the Ag was uniformly distributed on the surface of the solder matrix. The recommended content of the Ag to be added into the Sn–0.5Cu–3Bi solder alloy is 1.0 wt%. With the observed better properties it can be considered as the potential alternative to lead–tin alloy.

Graphical Abstract

中文翻译：

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Ag添加对三元无铅锡合金–Sn–0.5Cu–3Bi影响的实验研究

摘要

由于环境法规与铅的固有毒性有关，因此不能再在焊料中使用铅。本文研究了添加银（Ag）对三元无铅焊料合金Sn-0.5Cu-3Bi的熔融行为，微观结构和显微硬度的影响。还分析了Sn–0.5Cu–3Bi与Cu基板之间的接触角。使用感应炉，带有氩气的退火炉制备了在Sn–0.5Cu–3Bi中具有不同Ag百分比（0、0.25、0.5、0.75和1.0 wt％）的样品。使用TG-DTA分析进行了熔融温度测试，使用ICP-OES进行了化学成分测试，使用了维氏硬度计进行了硬度测试，并使用了场发射扫描电子显微镜对显微结构进行了测试。对获得的结果进行了彻底的分析。结果表明，Ag的添加对增强基础焊料合金的性能具有显着的积极作用。发现熔点随着Ag含量的增加而降低。添加银可改善硬度和接触角。微观结构观察表明，Ag均匀地分布在焊料基质的表面上。推荐添加到Sn–0.5Cu–3Bi焊料合金中的Ag的推荐含量为1.0 wt％。观察到更好的性能，可以认为它是铅锡合金的潜在替代品。微观结构观察表明，Ag均匀地分布在焊料基质的表面上。推荐添加到Sn–0.5Cu–3Bi焊料合金中的Ag的推荐含量为1.0 wt％。观察到更好的性能，可以认为它是铅锡合金的潜在替代品。微观结构观察表明，Ag均匀地分布在焊料基质的表面上。推荐添加到Sn–0.5Cu–3Bi焊料合金中的Ag的推荐含量为1.0 wt％。观察到更好的性能，可以认为它是铅锡合金的潜在替代品。

图形概要