Fault diagnosis of carbon fibre composite masts

Abstract

More often in the world, in many applications, composite materials replace traditionally applied materials like steel, aluminium alloys etc. Especially they have an application when the product must be light and should have specific mechanical and dynamic features, important for the sake of place of application and type of work. One of this application is the mast of high-performance sail boat. Applied materials in process of its production are expensive, and technology and process engineering are complicated and time-consuming. Mast, for the sake of characteristic kind of work and because it is very important constructional element, should have very big reliability. Other important thing is ability to early defect detection of reinforcement structure at the stage of production and then in the middle of operational use. This ability has large influence on safety of deck crew. One of the most often and invisible defect is enlarging of holes around rivets and bolts fasten mounting elements of rigging caused by strong dynamic overloads. In this paper Authors made an attempt to finding this kind of defects by vibroacoustic techniques and try to determine proper symptoms. Authors postulate that change of hole diameter should change dynamic response (transmittance) of a system on dynamic coercion.