Temperature Dependence of Strength at Both Fiber/Matrix and FRP/FRP Interfaces Using Different Matrix of Roving Cloth FRP

Fiber/Matrix Ratio=100/0, 0/100

Abstract

Previously, in the case that both the fiber/matrix and the FRP/FRP interfaces were constructed with the same matrix, the temperature dependence of the strength of roving glass cloth FRP in the flatwise direction was reported.
In this paper, two types of matrices having properties different from those of the matrix used in roving glass cloth FRP, were applied at the FRP/FRP interface, so as to construct the fiber/matrix and the FRP/FRP interfaces with different matrices. The relation between the fiber/matrix and the FRP/FRP interfaces and its dependence on matrix were studied by changing the fiber/matrix ratio, the condition of heat treatment and the temperature. The results obtained are as follows.
(1) The temperature dependence of the fracture behavior (brittle or ductile) of the interface was changed by both the type of matrix and the condition of heat treatment. But it was not affected by the location of the weakest interface.
(2) The temperature dependence of the location of the weakest interface was affected by both the type of matrix and the condition of heat treatment. But the influence of the fiber/matrix ratio on the temperature dependence of the location of the weakest interface varied with temperature.
(3) The temperature dependence of the bond strength was affected by the type of matrix, the condition of heat treatment and the location of the weakest interface. But the influence of the fiber/matrix ratio on the temperature dependence of the bond strength was changed by the type of matrix and the condition of heat treatment.
(4) In spite of the type of matrix examined, the bond strength varied with the temperature dependence of the bond strength for fiber/matrix ratio=100/0 and the bond strength varied with the temperature dependence of the location of the weakest interface for fiber/matrix ratio=0/100.