Statistical Investigation of Parameters Influence on Fracture Toughness of the Glass Fiber Reinforced Composites
The objective of the work was to investigate statistical analysis of fracture toughness of the glass fiber reinforced composites at different stacking sequences, strain rate and crack length. The glass reinforced vinylester composites prepared by hand layup technique with stacking sequences of 0/90, 45/-45 and chopped strand orientations. 3- point bending for fracture toughness test for various notch depth ratio's as per linear elastic fracture mechanics concept was conducted. Further the initial notch depth method was adopted to find the critical stress intensity factor KIC for the given notch depth ratio. Design of experiment using Taguchi L9 array was formulated to understand the influence of parameters on fracture toughness. The result of surface methodology showed the stacking sequence of (45/- 45/0/90/Chopped)3s, with strain rate of 0.5 mm/min and without notch having the highest fracture toughness of 81.36 Mpa
FRACTURE BEHAVIOR OF GLASS FIBER REINFORCED POLYMER COMPOSITE
This study investigates the effect of chapped strand glass fiber on fracture behavior of polymer composites. Chopped strand glass fiber reinforced particle-filled polymer composite beams with varying notch-to-depth ratios and different volume fractions of glass fibers were studied in Mode I fracture using three-point bending tests. Effects of polyester resin content and glass fiber content on fracture behavior was also studied. Polyester resin contents were used 13.00%%, 14.75%, 16.50%, 18.00% and 19.50%, and glass fiber contents were 1% and 1.5% of the total weight of the polymer composite system. Flexural strength of the polymer composite increases with an increase in polyester and fiber content. The critical stress intensity factor was determined by using several methods such as initial notch depth method, compliance method and J-integral method.
Damage mechanism and life prediction of graphite/epoxy composites
This paper describes observation of fatigue damage mechanism in composites subjected to compression dominated fatigue loading, formulation of a damage-indicating parameter based on the intralaminar microcracking of the resin, and its application in conjunction with a linear fatigue damage model to predict spectrum life of graphite/epoxy composite laminates.