Enhancement of interfacial reaction between solid iron and molten tin by mechanical actions

The influences of mechanical actions on interfacial reactions between an iron plate and molten tin were examined. Tensile and compressive stresses up to 100 MPa on the iron plate did not significantly change the thickness of the reaction layer and the corrosion depth of the plate. However, when the iron plate was subjected to repeated rubbing with tungsten and Pb–Sn eutectic alloy wires and when it was immersed in the rotating molten tin, the reaction layer thickness decreased and the corrosion depth of the iron plate increased. From these results, it was concluded that the corrosion of the iron plate in the molten tin was enhanced by repeated rubbing with the solder alloy on the plated iron layer and also by flow of molten solder alloy down the surface of the soldering tip in the soldering process.