Effects of temperature on the creep behaviour of woven and stitched composites

This paper presents an investigation of the tensile creep behaviour of woven fibre composite stitched, through the thickness, with cotton or carbon threads along the loading direction. Creep tests were conducted at various temperatures. It was found that the through-thickness stitching significantly improved the creep deformation and creep rupture resistance of these composites. The creep data were analysed using the 'time-temperature-stress superposition principle' theory (TTSSP). The long-term behaviour of the material could then be predicted by means of a master curve. Finite-element analyses of the composites was also carried out and the stitching was found to considerably reduce the interlaminar stresses. (C) 1997 Elsevier Science Ltd.