The 'natural ' metal-matrix composite formation by thermo-mechanical treatments

摘要

The progress in understanding the nature of strain localization in metallic materials and in particularunderstanding the role of external (deformation conditions) and internal (material substructure)factors in the development of the tendency toward concentration of plastic flow within transgranularshear bands is the background of the concept given in the title. Following this idea, the practicalpossibility of replacing the homogeneous in a micro-scale mode of deformation by transgrasnularshear bands gives a chance to change the arrangement of the dislocation substructure in the materialfrom that typical for homogeneous deformation into long wavelength (transgranular), pseudo-periodic dislocation walls. The presence or formation of such a substructure in a thermodynamicallyunstable matrix may result in the formation of the products of phase transformation along shear bands,giving rise to a composite-like structure. This work is aimed at providing a coherent justification to theconcept of a natural metal-matrix composite and summarizes the results of experimental work in thisarea.