Determination of elastic properties for a wound oxide ceramic composite

Kurzfassung

Abstract Thanks to its low cost and high flexibility, in the last few years the winding technique has been successfully adapted for the production of complex Ceramic Matrix Composite (CMC) components with load-oriented fibre alignment. Since the winding angle can be adjusted in any direction (from 0° to 90°) during the fabrication process, it is important for the design of components to evaluate the elastic properties of CMCs as a function of the winding angle. In this study, an inverse method based on the Classic Laminate Theory (CLT) has been used for the prediction of the elastic properties, i.e. Young’s modulus, shear modulus and Poisson’s ratio, for a wound oxide CMC material, called WHIPOX® (Wound HIghly Porous OXide ceramic matrix composite). For this purpose the characteristics of an equivalent unidirectional layer (UD-layer) with consideration of fibre volume content (FVC) and porosity were calculated. On the basis of microstructural analysis the computed WHIPOX®UDproperties have been divided into two sets of elastic properties for small (below 30°) and large winding angles (30° and above). Full coverage of the mechanical properties in different wound orientations, non-orthogonal with ±3°/±87°, ±15°/±75°, ±30°/±60° and orthogonal with ±45° and 0°/90°, were evaluated with in-plane tension, and Iosipescu-shear tests. A good correlation between experimental and analytically calculated results is shown in this paper.