Transverse tensile behavior of carbon fiber/epoxy composite at different temperatures and strain rates

Abstract

AbstractThis research explores the transverse tensile properties of a unidirectional carbon fiber/epoxy composite under quasi‐static and dynamic conditions, across various temperatures (−30, 25, 85°C). To conduct the investigation, a universal testing machine and a split Hopkinson tensile bar are utilized. The findings reveal that the transverse tensile properties are influenced by temperature and strain rate. At −30, and 25°C, the quasi‐static stress and strain curves exhibit linearity, while at 85, nonlinearity is observed. On the other hand, the dynamic stress and strain curves demonstrate approximate linearity across all temperatures. The quasi‐static tensile strength decreases with rising temperature, but the dynamic tensile strength remains relatively unaffected by temperature variations. Furthermore, both the quasi‐static and dynamic tensile elastic moduli decrease as temperature increases. The transverse tensile strength and elastic modulus exhibit an approximately linear relationship with the logarithm of the strain rate. The study also delves into the analysis of fracture morphologies and mechanisms through macroscopic and microscopic observations. By introducing the dynamic enhancement factor of strain rate, the formulas of the transverse tensile strength and elastic modulus at different temperatures are proposed. These formulas provide a comprehensive representation of the experimental results.Highlights Tensile properties at different temperatures and strain rates are tested. Stress and strain curves at various temperatures and strain rates are studied. Variation of tensile properties with temperature and strain rate is analyzed. Change of fracture mechanism with temperature and strain rate is discussed. Formulas for transverse tensile strength and elastic modulus are given.