Experiments and simulations on the strength of open-hole composite laminates at different temperatures

Abstract

With the development of the heat-resistant resin, carbon fiber resin matrix composites can service at high temperature condition. However, there are very few studies about the thermo-mechanical behavior at temperatures of the composites, and the temperature effects on composites are very complex. Open-hole composite structure is one of the typical bearing structures used in engineering widely. In order to capture the thermo-mechanical behaviors of the open-hole laminates, tensile tests and compressive tests of the open-hole T300/BMP316 laminate were conducted over a wider temperature range (from RT to 310 °C). Based on the experimental results, there occurs an inflection point in the curve of strength versus temperature of the open-hole T300/BMP316 laminates, and tensile strength and compressive strength have the similar variation rules when the temperature increases. In the temperature range from RT to 230 °C, both the tensile strength and compressive strength decrease with the rise of temperature. In the temperature range above 230 °C, both the tensile strength and compressive strength increase with temperature. The temperature effect on compressive strength is greater than on tensile strength. Based on the theory of progressive damage and 3D Hashin’s failure criteria, a strength prediction method considering temperature effects was developed and was used to describe the mechanical behaviors of open-hole T300/BMP316 laminate. Compared with the experimental results, the maximum error of predicted strengths is <7%, the fractures and the tendency of tensile/compressive strength varied with temperature obtained by simulations and experiments are similar, which illustrated that the strength prediction model considering temperature effects is effective.