Metallization of diamond/Al composite surface with Ni-P coating

In this study, a steady and comparatively smooth Ni-P coating on the surface of diamond/Al composite substrate was fabricated by electroless plating, which can outstandingly improve solderability of the composite. By controlling the deposition time, we obtained the growth curve of the Ni-P coating, and as a result we can adjust the thickness of the coating. The solderability was tested by soldering experiments with two typical solder materials, SAC305, representing lead-free solder, and Sn63Pb37, representing lead-content solder. Thermal storage test was conducted at different temperatures to analyze reliability of the coating. The formed IMCs during soldering and thermal storage were investigated by scanning electron microscope (SEM) and different IMCs in different solder were compared.