On the evaluation of the constrained studded pressing method for producing nanocrystalline copper sheets

Abstract

Abstract In this study, the experimental setup of a constrainedstudded- pressing method (CSP) as a severe plastic deformation process was investigated to produce nano-crystalline copper sheets. The sheets were CSPed up to 35 passes. The crystallite size and the dislocation density of CSPed samples were calculated by X-ray-diffraction pattern analysis. Also, tensile tests were used to investigate the mechanical properties of the CSPed samples. The results revealed that increasing the number of CSP passes augmented the density of dislocations, reduced the crystallite size to 124 nm (while for the as-received sample it was about 7.8 lm), enhanced the yield-strength and the ultimate-tensile- strength, and lowered the elongation of samples. This study for the first time has challenged the ability of the CSP method to produce nanocrystalline materials.