Simulation Methods for Life and Remaining Strength Prediction of High-Temperature Polymeric Composites Subjected to Cyclic Loads

摘要

The purpose of this paper is to establish and demonstrate a methodology for the prediction of the remaining strength and life of polymer-based composite laminates subjected to cyclic and sustained thermomechanical conditions. Conditions to be considered include elevated temperature (in air) and cyclic (fatigue) loading at various stress levels. The approach taken is to construct a simulation of the damage accumulation process and failure mode that controls the remaining strength and life for carbon fiber-reinforced K3B polymer matrix systems. The simulation is based on micromechanical and ply-level models of composite strength that combine the properties, geometry, and arrangement of the constituents to estimate the global strength as a function of those parameters. As applied conditions influence those parameters, those influences are combined to yield estimates of the remaining strength and life (when global strength is reduced to the level of the applied conditions). These predicted values for the remaining strength as a function of the number of fatigue cycles, temperature, and load level are in good agreement with available experimentally measured values.