Deformation stacking fault probability and dislocation microstructure of cold worked Cu–Sn–5Zn alloys by x-ray diffraction line profile analysis

Abstract

Plastically deformed (hand-filed) Cu–Sn–5Zn ternary alloys with Sn concentrations 1, 2.5, and 5wt% are investigated. Microstructural parameters are studied in terms of x-ray diffraction profile fitting analysis. It is observed by Dey et al. [Acta. Mater. 53, 4635 (2005)] that the change in stacking fault probability (α) with Sn concentration for ternary Cu–Sn–5Zn alloys is similar to Cu-based binary alloy (Cu–Sn) system but behaves in a different manner from Cu–1Sn–Zn ternary alloy systems. The crystallite size distribution is broader for alloy with 1wt% Sn and becomes narrower with increasing Sn concentration. Value of dislocation density (ρ) is of the order of 1015m−2 and shows a compositional dependence. Type of dislocation is found to be predominantly screw; ⟨100⟩-type dipoles may also be present in the cold-worked alloys. The dislocation arrangement is found to be more correlated in case of 1wt% Sn compared to other alloys of higher Sn concentration. The stacking fault energy (γ) is obtained from modified Reed-Schramm equation and is of the order of 20mJm−2 with no significant compositional dependence.