Numerical study on local effects of composition and geometry in self-healing solders

This paper introduces a numerical approach dealing with self-healing of solder materials, with detailed discussion of the damage and healing behavior of solder joints through creep deformation. The description of damage- and subsequent healing processes was done within the continuum damage mechanics (CDM) framework, assuming the formation of voids in the material due to creep deformation. The presented model considers a potential healing effect by void closure due to viscous flow of the solder-material and capillary forces. It is assumed that partial melting of a two-phase solder material facilitates this effect. The proposed healing model introduces a concept to describe void closing effects under consideration of phase transformation by using exemplary Sn-Bi alloys.