Deformation-induced nanocrystallization and its influence on work hardening in a bulk amorphous matrix composite

With the development of various processes to produce bulk amorphous composites with enhanced plasticity, investigations of the mechanical behaviors of the amorphous alloys in the plastic regime have now become feasible. In addition to dramatically enhanced plasticity, some bulk amorphous composites have exhibited a work hardening behavior during plastic deformation. Considering that most strengthening mechanisms, Such as solid solution hardening, martensitic hardening, etc., operative in crystalline metals are associated with dislocations, the work hardening behavior observed from amorphous composites, where dislocations do not exist, is of a special scientific interest. We have observed that quasistatic compression imposed to the amorphous composite induces the homogeneous precipitation of nanocrystallites from the amorphous matrix of the composite, which, in turn, leads to strengthening the amorphous composite. The strengthening mechanism of the amorphous matrix composite is investigated as well. (C) 2003 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.