Carbon plain-weave fabric low-temperature vacuum cure epoxy composite: static and fatigue strength at room and high temperatures and practicality evaluation

The high cost of carbon fiber composite materials is a large barrier to their increased application. Low-temperature vacuum cure epoxy resins were developed as one way to break through this barrier. This kind of epoxy is initially cured at low-temperature in a vacuum bag and post-cured at high temperature in an air-circulating oven. This study investigated the static and fatigue mechanical properties of a low-price CFRP of this kind and evaluated its practical utility. The material tested was TRK180M carbon plain-weave-fabric/1053 low-temperature vacuum cure epoxy laminate with quasi-isotropic lay up. Static tests provided tensile and compressive strength of non-hole and open-hole specimens at room and high temperatures up to 110 degrees C. Tension, compression, and tension-compression fatigue tests determined S-N relationships of open-hole specimens at room temperature and 110 degrees C. Static tensile and compressive damage in non-hole specimens and fatigue damage in open-hole specimens for three kinds of fatigue tests were observed with a CCD microscope and a micro X-ray CT scanner. Test results are compared with other published results and discussed from a practical viewpoint. The tests pointed out the evaluation of the strength related to compression loading and sensitive to matrix damage to be very important and demonstrated the sufficient practical utility of this material.