OPTIMISING PROCESS PARAMETERS FOR FABRICATING AA4047 MULTI-LAYER WALL BY COLD METAL TRANSFER BASED WIRE ARC ADDITIVE MANUFACTURING (CMT-WAAM) AND STUDYING ITS MECHANICAL PROPERTIES

Abstract

This paper aims to fabricate multilayer wall of AA4047 by Wire Arc Additive Manufacturing (WAAM) through Cold Metal Transfer (CMT). To determine the optimal process parameters, optimization of monolayer parameters is carried out via Response Surface Methodology (RSM) – Analysis of Variance (ANOVA). There is an overall impact on the operational characteristics of fabrication time, and heat input (HI); geometrical characteristics of wall height, and width; and metallurgical characteristics of strength, microhardness, porosity, and microstructure for the deposited layers. The multilayer wall had average Microhardness of 49.90 HV, Yield Strength of 67.5 MPa, Elastic Modulus of 1032.58 MPa, Percentage Elongation (PE) of 31.3, and Ultimate Tensile Strength (UTS) of 146.5615 MPa. It was concluded that UTS, and microhardness increased, and deposition rate, PE and pore size decreased, as HI was decreased by decreasing current and increasing travel speed, on increasing the number of layers.