LD31铝合金电刷镀SnPb钎料合金软钎焊

Soldering of LD31 aluminum alloy with electro brush plated Sn-Pb alloys

采用在LD31表面电刷镍阻挡层、铜改性层,将LD31铝合金的连接转化为铜的连接,在镀铜层的表面电刷镀SnPb钎料直接进行钎焊,通过开发低应力镀镍液和调整电刷镀工艺参数解决镍过渡层的裂纹问题,研究分析了镀层的显微结构及表面状态,焊缝的结构及元素分布,考察了焊接加热过程对镀层的影响。研究表明,通过在镀铜层表面直接刷镀SnPb钎料合金可以实现软钎焊连接,接头的抗剪强度可达20MPa,镀镍层、镀铜层钎焊后无裂纹、剥离等缺陷产生。

The bonding of LD31 aluminum alloy with electron brush plated Sn-Pb solder after the deposition of Ni and Cu transient layers was investigated in this paper. The influence of electric deposition parameters of SnPb alloy on the coating quality and subsequent solderability was studied. The constitution of coatings, the morphology of Sn-Pb coating, the bonding mechanism in the soldering and the elements distribution in the soldered joint were studied by scanning electron microscope, energy dispersive X-ray analysis and metallographic analysis. The results of soldering experiment showed that after the deposition of Ni and Cu coatings, the bonding of LD31 aluminum alloy could be transformed to the bonding of copper, and the bonding of coatings could bear the heating condition in the soldered. The shear strength of the soldered joint could reach as high as 20 MPa.