Elevated temperature testing for comparison of glass/resin composites

Abstract Static test methods were used to evaluate and compare the thermal and mechanical properties of several glass/thermoset laminated composites between 25° and 400°C. The unidirectional matrix composites consisted of phenolic‐modified epoxy, epoxy novolac, epoxy, and modified phenolic resins. These materials were selected as potential alternative materials for rotary compressor vanes. Dynamic mechanical analysis (DMA), thermomechanical analysis (TMA), and thermogravimetric analysis (TGA) techniques were selected to evaluate elevated temperature performance. The short‐beam shear test was chosen to measure interlaminar shear properties. The results indicated that an elevated‐temperature matrix, such as the modified phenolic resin, may not result in optimum composite strengths. Instead, an epoxy resin reinforced with glass fibers provides a better balance between elevated‐temperature performance and interlaminar shear strength. The test results of this study, in addition to being adequate for discriminating the materials for initial selection purposes, were obtained quickly and easily. Moreover, the thermal results provide a more realistic understanding of composite elevated‐temperature characteristic than do those of the present standard test.