Growth of eutectic thin film structures

Abstract

A nonlinear model of eutectic growth yields the shape of the irregular interface in which the triple points are displaced both parallel and perpendicular to the interface. The spacing of the eutectic film is controlled by the formation of faults below a critical spacing and by catastrophic breakdown in the interface shape at larger spacings. The stable growth range decreases with increasing perturbation amplitude. Local regions of large spacing that originate from defects in the eutectic thin film, produce a wave of bent plates which with time eliminate the initial spacing variation. Simulated microstructures derived from this model correspond to structures of directionally solidified eutectic thin films. The mechanics of eutectic thin film growth arediscussed.