低温Sn-Bi焊料用溶剂的优化设计

Optimization of Solvent for Low Temperature Sn-Bi Solders

为减少焊接前期工作量以及降低成本,采用正交试验法对Sn-Bi焊料用助焊剂中溶剂成分进行了优化设计。以焊膏铺展性能和焊点形貌作为评价指标,对单一溶剂和复配溶剂进行优选。结果表明:单配溶剂制备得到的焊膏铺展性能差、焊点不规则,残留物多;而复配溶剂制备得到的焊膏铺展率较大,焊点外形饱满、表面氧化物少。X醇、异戊醇、Y醚的比例为2:1:2时铺展率可达83.18%。焊料的微观组织分析也表明,在最优条件下的焊料在铜基板上铺展好,且焊缝界面区域无缺陷,助焊效果良好。

In order to reduce the prophase workload and cost, composition of solvent in flux for Sn-Bi solder was optimized by orthogonal experiment.The optimization of single solvent and mixed solvents was carried out through taking soldering with the spreadability and morphology as the indexes.The results show that the solvent paste prepared with single has the poor spreadabilities, irregular spots and more residues; while the mixed solvent paste has good spreadabilities, full spots and less residues. When the proportion of x-alcohol, isoamyl alcohol, and y-ether is 2：1：2, the spreadability of solder paste is 83.18%. According to the microstructure analysis of solder ,it is known that the solder has good spreadability on copper, defectless in the interface area of the weld,and perfect welding effect.