EFFECT OF MACHINING PROCESS PARAMETERS AND NUMBER OF PASS ON COMPACTION BEHAvIOUR OF COMMERCIALLY PURE ALUMINIUM CHIPS CONSOLIDATED BY EQUAL CHANNEL ANGULAR PRESSING (ECAP) USING RESPONSE SURFACE METHODOLOGY

This work investigates the compaction behaviour of commercial pure aluminium chips (CP Al) produced during a machin-ing operation and subsequently consolidated by Equal Channel Angular Pressing (ECAP). Empirical models were developed to describe the relative density and hardness of the compacted product of ECAP as functions of the initial machining input parameters including cutting edge angle (CA), depth of cut (DOC) and then the number of consolidation pass during ECAP. The models were developed utilizing response surface methodology (RSM) based on data from a central composite face centred factorial design of experiments approach. The models were then validated by using Analysis of Variance (ANOVA). The effect of input parameters on the relative density and hardness of the ECAP consolidated samples are presented and discussed including details as regards to the mechanical and microstructural properties. An optimum set of input parameters are identified and presented where the best relative density and hardness are demonstrated.