Parameters Inversion of Adhesive Interface of Solid Rocket Motor Based on DIC Method

Abstract

Aiming at the problem that the cohesive zone model parameters，describing the mechanical properties of the adhesive interface，which can't be obtained by traditional experimental method accurately，the inversion research on the relevant parameters of bilinear cohesive zone model used for the adhesive interface is carried out by using the digital image correlation method and Hooke‑Jeeves optimization algorithm based on the tensile test results of solid rocket motor rectangular adhesive specimens. The inversion results show that the maximum adhesive strength，modulus and failure fracture energy are 0.55 MPa，0.57 MPa and 2.26 kJ·m-2，respectively，when the tensile rate is 5 mm·min-1. The relative error of simulated and measured stress‑strain curves is corrected from 44.7% to 4.3%. When the tensile strain is 0.05 and 0.08，the maximum displacement errors of simulated and measured region of interest is 0.64 mm and 1.76 mm，respectively，and the average displacement errors of simulated and measured region of interest is 0.38 mm and 0.45 mm，respectively. The validation results indicate that the accuracy of the inversion identification method is high enough and the established cohesive zone model can be used to characterize the mechanical properties of the adhesive interface.