Study on the mechanical properties of functionally graded material made by centrifugal method

A simple definition of functional graded material (FGM) includes composite with inhomogeneous micro-structure that made by at least two components. The properties of FGMs vary along the the material thickness. The centrifugal procedure is a useful method to fabricate a FGM material. Different parameters of centrifugal method effect on the distribution of the reinforcement material. In this study, copper, iron, SiC and alumina powders were used as reinforcements and a polyester resin employed as the matrix. In manufacturing process of mentioned materials, powders with specific volumetric ratio, mixed with the resin and poured into the rotary mold. By attention to centrifugal force, powder paricles found specific position in the resin. Captured images from the surface of fabricated FGM tubes and distribution of particles were analysed by image processing. Three point bending tests were used to measure the strength of material according to ASTM D790 standard. The results showed that the rotational speed of mold is the most effective parameter on the distribution of reinforcement particles. Therefore, by increasing the speed from 250 to 500 rpm, slope of distribution of reinforcement particles increased. The results of the bending test showed that employment of reinforcement particles with more strength and volume led to increase the strength and module of fabricated FGMs.