Effects of deformation on microstructure of Cu-Zn-Ni alloy

Abstract

The thermal and mechanical effects on microstructure of Cu-12.44%Zn-4.75%Ni (wt%) alloy were investigated. The effects mechanical on both rapidly cooled sample and slowly cooled sample obtained from Cu-Zn-Ni alloy were investigated by using scanning electron microscopy (SEM), X-ray diffraction techniques (XRD). The thermal energy changes of in the alloy were examined by means of differential scanning calorimetry (DSC). As a result of SEM observations, annealing twins structures are observed in rapidly and slowly cooled samples. According to pictures of the SEM and XRD, the stress applied to samples caused to lose existing annealing twins, and led to formation of slip planes lying parallel to each other in between plates. The stress-strain behavior is associated with applied heat treatment effect to samples. It's shown that the intensities of XRD peaks to be decrease, as a result of the increase in cooling rate. This result indicates that density defects of crystal increases with rapidly cooled in the Cu-Zn-Ni alloy. In both samples of the thermal energy changes, at the process of diffusion transformation eutectoid separation reactions have been proved to exist.