MORPHOLOGICAL INSTABILITIES OF A STRESSED PORE CHANNEL

Under surface or bulk diffusion, a pore channel can lose its cylindric al shape by Rayleigh instabilities, transforming into cavities to mini mize surface energy. When the solid is stressed, the surface fluctuati ons relax partially the stored elastic energy and increase the instabi lity. Calculations show that the new critical wavelength is shifted co ntinuously towards shorter values as the stress is increased. Surface diffusion considerations permit the determination of the most probable wavelength to appear and the increase of instability growing rate wit h applied stress. (C) 1997 Acta Metallurgica Inc.