Microstructure and mechanical propeties of new leadfree SAC and activated carbon composite solder

Abstract

Recently, composite solder gain researcher attention in providing reinforcement candidate for lead solder. In this research, SAC and activated carbon synthesized to develop a new composite solder candidate. Four parameter of lead free solder which are (0%, 0.5%, 1.0%, 1.5%) of activated carbon are compared when considering their use in lead-free soldering process. The IMC and microstructure for all composite solder were observed. Scanning Electron Microscope was used to analyse the intermetallic compound (IMC) that formed between the sandwich of the solder joint and the copper substrate. The phases exist were determined by Energy Dispersive X-Ray (EDX) and supported by X-Ray Diffraction (XRD) analysis. The IMC phases found in both solders were Cu3Sn and Cu6Sn5 with the addition of AC phases in SAC/AC composite solder. The Optical microscope was used for microstructure analysis. The IMC layer shape has changed from scallop type to the combination of planar and scallop shape with the addition of AC particles where the planar shape is favorable shape for IMC. Practically, with the existence of AC in the solder, the hardness value is higher and indicate the improvement of the mechanical properties.