Simulation analysis of plastic deformation of polyurethane foam by multi-cycle loading

The article is devoted to analyzing the effect of plastic deformations in structurally heterogeneous materials on the change in their mechanical behavior under the action of non-stationary multi-cycle loading. The problem is solved in the framework of Cosserat elasticity. It allows us to consider the influence of the discreteness and heterogeneity of the material structure. The developed approach is based on applying the indirect method of boundary elements, developed for the case of non-stationary problems of the moment theory of elasticity using the time Fourier transform. Evaluating changes in mechanical, physical, and microstructure characteristics in polyurethane foam based on the results of experimental investigations. Experimental studies were conducted on a series of polyurethane foam samples with different component compositions. Based on the methodology developed in [4], an analysis of the change in the distribution of normalized radial stresses in the inner layers of the environment was carried out, taking into account the change in mechanical, physical and microstructure characteristics. The developed approach makes it possible to estimate the residual life of bodies made of foam materials during operation in extreme conditions, where plastic deformations of the environment are possible.