CONTINUUM PREDICTIONS OF DEFORMATION IN COMPOSITES WITH TWO CREEPING PHASES--I. MODEL SYSTEMS

摘要

Analytical and finite element (FE) method continuum analyses of deformation are described for model composites in which both phases exhibit either transient or steady-state creep. Both models predict that the presence of a weak ductile phase within a strong matrix, e.g. ductile-phase toughened intermetallic matrix composites, degrades the creep resistance of the strong phase less severely with decreases in: (1) the stress exponent of the matrix; (2) the volume fraction of the discontinuous ductile phase; and (3) the creep rate of the ductile phase. The FE models predict potential locations for creep damage within the composite, and that the steady-state creep rate of strong-matrix composites is nearly independent of the reinforcement geometry.