Polymer-based composite fatigue life prediction method based on mesomechanics

Abstract

The invention discloses a polymer-based composite fatigue life prediction method based on mesomechanics. The performance research object of a polymer-based composite is determined, and the performanceresearch object comprises fibers, a base and a fiber-base interface; according to the constitutive relation and the S-N curve of the performance research object, an equivalent volume unit model is repeatedly stacked to construct an equivalent regular fiber array; the multi-axis time-varying mesoscopic stress of the polymer-based composite laminate under the action of the static load and the fatigue load is determined by utilizing the unit body model; the given mesoscopic stress of each performance research object is converted into an equivalent average stress and an equivalent stress amplitude; according to the equivalent average stress and the equivalent stress amplitude, the cycle index of fatigue failure is obtained in combination with a creep rupture kinetic model, and an equivalent life diagram is established for predicting the creep / fatigue life. The method is beneficial for people to effectively predict the service life of the equipment made of the polymer-based composite, so that the method has guiding significance for normal and efficient use of the equipment.

Description

technical field [0001] The invention relates to a method for predicting the fatigue life of a polymer-based composite material based on mesomechanics, and belongs to the technical field of composite material fatigue monitoring. Background technique [0002] Polymer matrix composites (PMCs) are widely used as metal substitutes in many applications due to their superior specific strength and specific stiffness. However, due to the inherent anisotropy and mesoscopic heterogeneity of composite materials, the traditional fatigue life prediction methods for metal materials are not suitable for composite materials. Therefore, the fatigue life prediction of composite materials has always been the focus of attention. In recent years, a lot of research has been done on the fatigue life prediction of composite materials. [0003] In the prior art, there exists an asymmetric iso-life diagram (CLD) model scheme, an asymmetric constant life curve anchored at static tensile and compressiv...

AI Technical Summary

Problems solved by technology

Most of the current methods are based on composite single layer (UD), and it is often difficult to identify critical components and failure modes

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