Avaliação numérica e experimental de insertos cerâmicos em materiais compósitos

Abstract

This paper aims to determine the pros and cons of using ceramic inserts on carbon fibrereinforced plastics (CFRP) components with respect to thermal and mechanical behavior. It is well known that, for such applications, the difference between the coefficient of expansion of the CFRP part and the metallic insert generates thermal stresses that can reduce the lifespan of these components due to fatigue and/or introduce local failures that reduce the efficiency of load introduction points. Furthermore, metallic inserts are susceptible to electrochemical corrosion when in contact with CFRP parts. Since ceramic materials are inert to this effect and have a similar coefficient of expansion to CFRP components, an evaluation of the mechanical behavior of ceramic inserts is proposed under mechanical and thermal loading. A bolt-joint insert is proposed, and alumina, steel, aluminum, and titanium inserts were produced. Simple geometry was proposed and comparative analyses, both numerical and experimental, were performed. Key results have shown that the performance of alumina inserts was better than the metallic ones under both high and low temperatures. Good agreement was found between the numerical and experimental approaches.