Control of macrostructure in deformation processing of metal/metal laminates

A study was carried out on model systems deformed under plane-strain. Finite element analysis was used to examine continuously and discontinuously layered models, in which the reinforcement to matrix flow stress ratio, rs, was varied within the range 1.5 < rs < 10. It was found that, for homogeneous refinement of continuously reinforced laminates, the critical value of rs is approximately 2. This value, valid for the ideal plastic case, can be increased to a maximum value of rs ≈5 with work hardening. For discontinuously layered systems, similar results were found. It is therefore concluded that macrostructural control is possible in metal/metal systems either in the form of homogeneous refinement of the continuous structures or in the form of structures with thin, long, closely spaced reinforcements, provided that the flow strength of the reinforcement is not more than five times that of the matrix.