Effect of different hostile solutions on mechanical properties of composite materials

Abstract

Due to their excellent performances in terms of high specific strength and stiffness, good static and dynamic properties, good corrosion resistance, adjustable properties, competitive cost, and quick manufacture, fibre-reinforced composites have been used in a variety of engineering fields, and this trend is expected to continue. In this context, these materials are subjected to a variety of environmental conditions, which have a major impact on their mechanical characteristics. Although several studies have been published on the influence of hostile solutions on low velocity impact response, the flexural fatigue performance of composite laminates exposure to corrosive solutions still has some lack of studies. As a result, the goal of this research is to investigate the low velocity impact and flexural fatigue evaluation of Kevlar/epoxy laminates after immersion in Sulphuric acid (H2SO4), diesel and seawater. For this purpose, static three-point bending tests were performed at a displacement rate of 2 mm/min. The low velocity impact tests were made using a drop weight testing machine IMATEK-IM10. Flexural fatigue tests were carried out in flexural mode using an Instron servohydraulic machine. Constant amplitude loading tests were performed at room temperature, under a stress ratio of R = 0.05 and frequency of 2 Hz. It was concluded that the different solutions affect flexural and impact behaviour of the studied materials, but the exposure time was determinant on the mechanical properties’ degradation.