Influence of technological factors on dispersion strengthened materials deformation mechanism studied by 'in-situ tensile test in SEM'

摘要

Direct observation of deformation process until formation of fracture on extreme small samples of composite in SEM is interesting from practical and interpretation aspects. In the present work the effects of composite composition, volume fractions of secondary phases as well as the matrix grain sizes (micro and nano size) on deformation and failure processes of Al and Cu-based composites were evaluated. Experimental materials were prepared by the different powder metallurgy methods. Interpretation of results was based on the quantification of the physical parameters of material phases depending on the preparation methods and on the analysis of deformation processes using the 'in-situ tensile test in SEM'. The mechanism of deformation and fracture for each composite system was estimated and models of fracture were proposed.