Effect of temperature on the transition from mild to severe reciprocating wear characteristics of A356-15% SiCp functionally graded composite

Modern technological applications demand engineering parts and structures that have specific property requirements and performance at certain locations. Functionally graded material can be used to serve such requirements, where the microstructure and percentage of composition can be varied with respect to the specific function at that region. The present study deals with the processing, microstructural characterization, and hardness evaluation of functionally graded A356-15 % SiCp metal matrix composite. The A356-15% SiCp Functionally Graded Metal Matrix Composite (FGMMC) is prepared by vertical centrifugal casting technique. Optical microscopy is used to evaluate the gradient distribution of the reinforced SiCp and microstructure of prepared FGMMC. The variation in hardness values along the radial direction due to gradation of SiCp is correlated with the microstructure variation. Wear behaviour of A356-15% SiCp FGMMC test pins taken from outer SiCp rich and inner alloy region is studied for a constant sliding distance of 350m and sliding velocity of 1m/s. The temperature induced wear transition of A356-15% SiCp FGMMC is analyzed under different loading conditions of 60N, 75N, 90N and 105N for particle rich outer pin from room temperature to 350°C. The transition temperature for change in wear behaviour is found to be 200°C and the transition load noticed at 75N for the outer pin. Similarly the inner pin was tested under loads of 45N and 60N for same temperature range. The wear debris collected and the stereo images of worn surface were clearly examined to study the temperature induced wear transition behavior. The outer pin show good wear resistance than inner pin till 60N load even at high temperature up to 350°C due to the SiCp reinforcement.