FORMALIZATION OF THE VIRTUAL EVALUATION OF STRAIN INTENSITY IN SPDed COMMERCIALLY PURE COPPER BILLET

Abstract

This work presented the results of solution of the strain intensity evolution in a commercially pure copper billet in the process of severe plastic deformation (SPD) by equal channel angular pressing (ECAP) technique. At the stage of the modeling task preparation, the most significant factors affecting the strain intensity at ECAP are suggested to be the friction coefficient, as well as the deformation velocity. A computer virtual full factorial experiment (FFE) was conducted accompanied with the application program package “DEFORM-3D” by using two-level model with two unknown varied parameters, followed by the formalization of the results in the form of the regression equation, as well as the optimization of the selected factors. The deformation velocity which coincides with the punch displacement velocity and the friction factor were chosen as independent variables in the ECAP process of characterizing the processing and its effectiveness, which are in terms of strain intensity; whereas the strain intensity of the material was selected as a response variable (dependent variable). Based on the results of the friction coefficient (f.) determination and the strain intensity estimated value of 1.155, a friction coefficient priori was determined to be 0.10. Therefore, the deformation velocity (V) of 1.5 mm/s was obtained by solving the regression equation.