Metallurgical and mechanical properties of marine grade AA5356 using wire arc additive manufacturing

In the current work, a Gas metal arc welding (GMAW)-based Wire Arc Additive Manufacturing (WAAM) procedure was used to build a wall construction of measuring Aluminium alloy (AA) AA5356 on an AA5083 base plate. The microstructure and mechanical properties of AA5356 were examined at two places along the wall structure’s horizontal deposition direction and in two deposition orientations (horizontal and vertical). Optical microscopy, SEM, EDAX, and fractographical examinations were used to analyse the microstructure. Tensile and microhardness tests were performed at two wall locations to evaluate mechanical parameters. A microstructure analysis reveals a mixture of columnar grain structure and coarser intermetallics in the remelting zone, with finer granular structure in the central region. The horizontal direction of AA5356 deposition exhibited a highest elongation and tensile strength of 4.4% and 249 MPa than the vertical direction. For the horizontal and vertical orientations, the average microhardness values were determined to be 80 HV and 72 HV, respectively. Fracture analysis of the tensile samples showed that the deposited metal had a ductile mode of failure with a predominance of dimples with tearing shape. This study provides valuable insights into constructing wall structures and analyzing their mechanical properties.