Study of deformation stacking faults and dislocation microstructures in Cu-1Sn-Zn alloys

Microstructural parameters of plastically deformed (hand filed) Cu-1Sn-Zn ternary alloys with zinc concentration 10-24 wt.% are studied with X-ray diffraction line profile analysis. It is observed that unlike the binary alloy system, the stacking fault probability calculated from peak shift analysis is almost constant with increase in zinc concentration from 10 to 20 wt.% and thereafter increases with the increase of zinc concentration. Stacking fault energy is calculated by modifying the expression given by Reed and Schramm [J Appl Phys 1974;45:4705] and shows a significant difference with that from earlier work by Ghosh and Sen Gupta [J Appl Phys 1983;54:6652]. Present results are closer to electron microscope studies. It is found that dislocation density is much higher (~10^15 m^-2) and shows compositional dependence. Dislocation type is found to be a combination of equal populations of screw and edge dislocations. It is noticed from dislocation arrangement parameters that the dislocations are greatly correlated in nature for lower Zn concentration and less correlated at higher Zn concentration.