Ag元素含量对Sn-Ag-Cu钎料焊接性的影响

Effect of Ag content on soldering ability of Sn-Ag-Cu solders

摘要: 以Sn-xAg-0.5Cu为基体制备了低银无铅钎料,其中Ag元素的质量分数分别为0.3%,0.5%,0.7%,0.9%.借助钎料合金的DSC熔化曲线,分析了Ag元素含量对合金熔点的影响规律.通过比较各组钎料合金在Cu基板上的铺展面积和铺展率,分析了Ag元素含量的变化对各组钎料润湿性的影响规律.结果表明,随着Ag元素含量的增大,钎料熔点降低,熔程缩短,钎料的熔化曲线吸热峰分布和形态发生明显变化;随着Ag元素含量的增加,钎料润湿性下降.综合考虑Ag元素含量对钎料熔点和润湿性的影响,认为Sn-0.7Ag-0.5Cu焊接性相对较好.

Abstract: The influences of Ag content on melting temperature and wettability of Sn-xAg-0.5Cu(x=0.3,0.5,0.7,0.9) lead-free solder alloys were studied.The melting temperatures of alloys were compared by DSC(differential scanning calorimetry) curves and the wettability was compared by the area and rate of wetting on Cu substrate.The experimental results indicate that alloys with higher Ag content have lower melting points and melting range,and the content of Ag in solder alloys has a significant impact on the distribution and profile of the DSC curves.However,with the Ag content increasing,the wettability of the alloys degrades.By combining the two key properties of solder alloy,melting temperature and wettability,Sn-0.7Ag-0.5Cu shows higher performance.