Keywords

Abstract

S-2 glass/epoxy; 

Fracture toughness; 

Strain energy release rate; 

 J-integral method; 

Deformation rate; 

Temperature effect; 

Finite Element Method

S-2 glass fiber draws attention because of its higher strength and elasticity module compared to other glass fiber types. When cracks occur on these structures, which have their distinctive strength properties, they may suddenly lose their physical life or in a shorter time than they should be. In this study, the fracture behaviors of S-2 glass fiber reinforced composite materials for different temperatures, deformation rate, and crack geometry were investigated. To investigate the effects of crack geometry on fracture behavior, cracks were formed on S-2 glass/epoxy composites in two different lengths (10mm and 15mm) and at two different angles (0° and 45°). Fracture tests were performed at two different environments impending cold (-20°C) and hot (80°C), and three different tensile strain rates (8.3×10-3, 8.3×10-4, and 8.3×10-5 s-1). For these experimental conditions, opening mode (Mode I) and mixed-mode (Mode I/II) fracture toughness values (KC) and strain energy release rates (GC) were investigated experimentally and numerically. The Jintegral method was used to calculate numerical fracture toughness. Experimental results have shown that fracture toughness increases with increasing temperature and crack length in general. As the deformation rate increases, fracture toughness decreases. Also, identical expressions that define experimentally and numerically calculated fracture were found close to each other. Jintegral method was found to be a successful method to analyze the fracture behavior of fiber-reinforced composites.

© 2021 MIM Research Group. All rights reserved.