The long term stability of multilayer materials composed of nonreactive, im
miscible materials is related to the equilibrium shapes of the individual g
rains within the layers. These shapes are determined by the free energies a
nd locations of the interfaces within the multilayer. We link the results o
f zero creep experiments with measured grain boundary groove angles to unde
rstand experimental observations of multilayer stability. (C) 1999 Acta Met
allurgica Inc.