Pii: S0266-3538(98)00185-7
نویسنده
چکیده
This paper concerns fatigue studies of polypropylene/glass-®bre thermoplastic composites produced from a bi-directional woven cloth of co-mingled E-glass ®bres and polypropylene ®bres with a ®bre volume fraction Vf of 0.338. The eect of lay-up design and load conditions on fatigue performance were investigated. The S-N curves, the rise in the temperature of the specimens, and the loss of stiness during the tests, are discussed. Fatigue tests were performed in controlled displacement mode and in an imposed stress range. Similar results were obtained for both load conditions. The loss of stinesswas used as a damage parameter and related to the rise of temperature. The results show that the damage parameter E present a nearly linear relationship with the rise in temperature. A small deviation was probably caused by the stress release observed in the ®rst period of fatigue life.# 1999 Elsevier Science Ltd. All rights reserved.
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