Modeling and simulation for the swelling behavior of unvulcanized rubber during the calendering process

Abstract

AbstractA comprehensive understanding of the swelling behavior of unvulcanized rubber during the calendering process is essential for the design of calendered products. In this work, the quasi‐static cyclic tensile experiments are carried out to investigate mechanical behaviors of unvulcanized rubber, including elasticity, inelasticity, and softening, as well as their strain‐rate dependences. Based on the obtained experimental results, a parallel network model consisting of a rate‐independent hyperelastic network and two rate‐dependent elastic‐viscoplastic networks is developed to characterize the constitutive behaviors of unvulcanized rubber. Then a steady‐state finite element method together with the constitutive model is proposed to explore the swelling behavior of unvulcanized rubber in the calendaring process. The divergence of thickness ratio between the simulation and experimental results is only 3.54%, which verifies the validity of the solution strategy. Besides, the effects of the calendar speeds and widths of unvulcanized rubber on swelling ratios are investigated. The numerical results show that the thickness/width swelling ratios increase/decrease rapidly with speeds from 1 m/min to 6 m/min, then tends to be stable at the speed of more than 6 m/min and widths hardly affect the variation laws of the swelling ratios with speeds.