Through-thickness compression testing of fabric reinforced composite materials: Adapted design of novel compression stamps

Abstract

The use of thick-walled fabric reinforced laminates in force transmission zones increased in the last years due to optimised production processes for composite structures. This enabled especially the manufacturing of thick laminates free of pores or other defects. As generally acknowledged, for a robust design and precise failure prediction of these structures reliable material property data are essential. While many test standards were analysed and modified in accordance to the specific characteristics of fibre reinforced materials, out-of-plane compression tests seem outdated. So far, some test methods are established; however, a standardised test method for compression testing in through-thickness direction of the laminate is still missing.A novel approach for through-thickness compression testing of fabric reinforced polymers with specifically designed stiffness-adapted compression stamps is presented. Comprehensive numerical analyses of the compressive load application and the dimensioning of the compression stamps in relation to the specimen size have been performed. It is shown, that the developed through-thickness compression testing device with the adapted design of the novel compression stamps is best suitable, as higher compressive strengths of fabric reinforced polymers can be experimentally determined.