Plastic Deformation of Fiber Coating in Polymer Matrix Composites under Hygrothermal Loading

Abstract

This paper is concerned with the study of elasto-plastic deformation of the coating, and consequently, the changes in the states of stress in the constituent phases of a unidirectional fiber reinforced polymer matrix composite (PMC) under uniform thermal, hygral and hygrothermal loadings. A four-phase composite cylinder assemblage (CCA) model has been used for the analysis. The coating interphase between the fiber and the matrix has been taken to be of lower modulus and lower yield stress value than that of the matrix. Only those combinations of temperature and moisture content are considered which give rise to plastic deformation in the coating, other phases still remaining elastic. Plastic behaviour of the coating has been idealized by taking a linear work-hardening constitutive relation.

Keywords

hygrothermal effect fiber coating coating deformation plastic relaxation of coating polymer-matrix composite stresses in fiber coatings

References

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