Anisotropic springback models of FCC metal material under severe plastic compressive deformation

Abstract

Accurate prediction of springback under severe plastic deformation is necessary for the geometric error in precision forming process, in order to establish accurate model of saturated springback under bulk forming. In this paper, the springback behavior and prediction model of anisotropic face-centered cubic (FCC) crystal copper alloy under severe plastic compressive deformation (SPCD) were studied from micro-perspective and macro-perspective. From the micro-perspective, a mathematical model of springback was established based on physical and mechanics mechanisms for predicting the saturated springback of the SPCD. Subsequently, from the macro-perspective, the effects of the macro variables including stress, strain, applied load, deformed surface area, external work, etc., on the saturated springback of quasi-static SPCD were discussed, and a anisotropic springback model of FCC material for the quasi-static SPCD process in a Gaussian form was set up based on above discussion and the expression of the proposed mathematical model of springback. Furthermore, the non-quasi-static anisotropic springback model containing comprehensive effect factor and size effect factor was proposed to predict the saturated springback of copper alloy after rolling process. The results indicated that the proposed springback models based on physical mechanism and macro variables can accurately predict the saturated springback of the anisotropic copper alloy under the SPCD. By introducing comprehensive effect and size effect factors, the anisotropic springback model for the non-quasi-static SPCD process has higher accuracy in predicting the saturated springback of bulk forming process. The present study revealed the springback behavior of anisotropic FCC copper alloy, and proposed accurate prediction models of saturated springback, which are of great significance to adjust the forming process and compensate the springback error of the FCC metal material during the bulk forming process.