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

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.