For more than 7 years,our research work is focussed upon the electrical behavior of carbon fiber reinforced composites.Effectively carbon/polymeric matrix laminates can be considered as an electri-cally conductive net...For more than 7 years,our research work is focussed upon the electrical behavior of carbon fiber reinforced composites.Effectively carbon/polymeric matrix laminates can be considered as an electri-cally conductive network(i.e.carbon fibers)embedded in an insulat-ing medium(i.e.the polymeric matrix).Consequently,from an electrical point of view laminated composites have been modelled owing to combinations of electrical resistances(i.e.fibers themselves and the contact points between the fibers)and capacitances(i.e.polymeric matrix).During their manufacturing,composite material such as thermoset matrix composites for instance,undergo various changes in their physical(including electrical and mechanical)prop-erties and in their geometrical characteristics.In fact,in the case of manufacturing processes such as oven curing(vacuum bag),auto-clave curing or heating plate press,beside the chemo-rheologi-cal changes,the laminated parts are the place of a compaction phenomenon inducing changes in fiber volume fraction and thick-nesses.The idea developed in this paper is that since the carbon/polymeric matrix laminate can be considered as an electrical network,it can then be view and used as a sensor for following the material state during the manufacturing process enabling thus defects to be detected and this without any additional sensing material or device.展开更多
文摘For more than 7 years,our research work is focussed upon the electrical behavior of carbon fiber reinforced composites.Effectively carbon/polymeric matrix laminates can be considered as an electri-cally conductive network(i.e.carbon fibers)embedded in an insulat-ing medium(i.e.the polymeric matrix).Consequently,from an electrical point of view laminated composites have been modelled owing to combinations of electrical resistances(i.e.fibers themselves and the contact points between the fibers)and capacitances(i.e.polymeric matrix).During their manufacturing,composite material such as thermoset matrix composites for instance,undergo various changes in their physical(including electrical and mechanical)prop-erties and in their geometrical characteristics.In fact,in the case of manufacturing processes such as oven curing(vacuum bag),auto-clave curing or heating plate press,beside the chemo-rheologi-cal changes,the laminated parts are the place of a compaction phenomenon inducing changes in fiber volume fraction and thick-nesses.The idea developed in this paper is that since the carbon/polymeric matrix laminate can be considered as an electrical network,it can then be view and used as a sensor for following the material state during the manufacturing process enabling thus defects to be detected and this without any additional sensing material or device.
