Experimental investigation of Al 7075 B4C composites for enhanced mechanical properties

Abstract

In general composite material gives the combination of two materials which uses the properties of both the material to give an improved mechanical and tribological properties Taguchi developed the offline quality improvement technique for the purpose of inspecting the products on line of the production process This technique is a systematic approach used for optimization of cost quality and performance In this work the experimental work pieces were produced from high purity Aluminum reinforced Al7075 reinforced with 5 Weight percentage wt 10 wt 15 wt and 20 wt commercial grade Boron Carbide B4C powder using the stir casting method The Al7075 aluminium flats are used to prepare the Metal Matrix Composite MMC and the B4C powder had an average size of 10 and#956;m In a stir casting process the reinforcing phases usually in powder form are distributed into molten aluminium by mechanical stirring Prior to mechanical stirring the surfaces of the stirrer must be properly cleaned in order to minimize the reaction between the stirrer and work material Introducing reinforcement particles to the stirred molten matrix sometimes will entrap not only the particles but also other impurities such as metal oxide and slag which is formed on the surface of the melt During pouring air envelopes may form between particles which can alter the interface properties between particles and the melt and also retarding the wettability A major concern associated with the stir casting method is the segregation of reinforcing particles which is caused by the surfacing or settling of reinforcement particles during melting and casting To prevent settling of particles a motor driven stirrer is used Taguchi technique is used to optimize the process parameter of workpiece sample with enhanced tensile strength newline newline newline