Description

Rotating disc forms an essential part of rotating machinery, namely turbines, compressors, automotive braking systems, ship propellers, computer disc drives etc. In most of these applications, the disc operates under elevated temperature and is simultaneously subjected to high centrifugal stresses caused rotation of the disc at high speed. As a result, the disc material undergoes significant creep deformations, thereby affecting overall performance of the system comprising of rotating disc. Functionally graded materials (FGMs) are a new generation of engineering materials, in which the constituents or their contents vary with respect to position coordinates, which enable them to offer unique performance. Most often, the FGM consists of ceramic and metallic constituents. The concept of FGM has been proposed with a view to obtain a new class of composite materials, consisting of heat resistant ceramic on the high temperature side and tough metals with high thermal conductivity on the low-temperature side, with a gradual variation in composition from the ceramic to metal phase.