Electroless Silver Plating of Al-Mg Filler Wire used in GMAW Process

Silver plating of 1.6 mm diameter Al-Mg filler wire of MIG welding process has been carried out by electroless plating method. The plating has been performed by dipping the wire in a cyanide bath of suitable composition. The effect of plating parameters such as the bath temperature and plating time on the characteristics of Silver plating has been studied. Microstructure studies on transverse section of the plated filler has been carried out under optical microscope to study the nature of plating and its adherence with the substrate at different plating parameters. The plated silver layer has been found well adhered with the Al-Mg substrate. The optimum plating parameters giving rise to significant amount of silver plating on the filler wire has been qualitatively identified. The amount of silver plating on the 1.6mm diameter Al-Mg filler wire, obtained by this process, has been analysed to be sufficient to introduce the minimum amount of silver required in Al-Mg MIG weld deposit to improve its resistance to stress corrosion cracking (SCC) susceptibility.