Design and structural testing of smart composite structures with embedded conductive thermoplastic film

The ongoing research and development of cost effective technology for remotely queried sensors for health and usage monitoring of composite structures has lead to the application of electrically conductive thermoplastic adhesive films. This paper intends to provide an in depth overview of a newly developed technology for the design and manufacturing of smart structures by introducing the application of electrically conductive thermoplastic adhesive films. The current technology is discussed and compared with this newly developed technology. It is shown that the structural aspects of this new technology are advantageous to the concept of smart structures as a whole. Fabrication and manufacturing techniques for this new technology is discussed, including the suitability of the process for automation. Specifically, standard tensile testing of the manufactured composite coupons with embedded thermoplastic conductive adhesive films have performed and compared to the test results from copper embedded coupons. The effect of embedded thermoplastic stripes on stiffness as well as strength of the parent laminated structure is evaluated and discussed. Furthermore, fatigue testing was performed at various ultimate failure strength percentiles to determine some degree of the fatigue life of the composite and the embedded conductive and insulting films. The conductive thermoplastic films are found to be structurally superior to copper when embedded in a composite structure, but the electrician conductivity is not as good as copper or other metallic conductors.