Investigating the microstructure and mechanical properties ofaluminum alloy thin wall with ER۲۳۱۹ welding wire by wire arcadditive manufacturing (WAAM)

Wire and Arc Additive Manufacturing (WAAM) technology is a new and cost-effectivemethod for manufacturing large-scale industrial parts. Since aluminum-copper alloys have wide andimportant applications in the aerospace and automotive industries, this has led to many studies on thesealloys. The most important challenges during producing parts from ۲۰۰۰ series alloys by WAAM areporosity and solidification cracking. In this study, a thin wall of aluminum alloy was produced withER۲۳۱۹ welding wire by WAAM method without solidification cracking by optimizing the weldingparameters. Furthermore, its microstructure and mechanical properties were investigated in the asweldedcondition and after post-weld heat treatment. The results of the tensile test of the samplesextracted from the wall show that the fracture strength of vertical samples is higher than that ofhorizontal and flat samples. The tensile test of the heat-treated samples show that the mechanicalproperties are improved due to the movement and uniform distribution of precipitates from the grainboundary to the inside of the grains during heat treatment. The wall hardness was on average about۷۸.۳ Vickers, and the difference in hardness values in different layers was due to different cooling ratesthrough the layers. In the optical microscope (OM) and scanning electron (SEM) images of the samplesbefore heat treatment, the accumulation of coarse Al۲Cu precipitates was observed. SEM images of thefracture cross-section of the tensile test samples showed that the samples had fractured ductilely alongthe fine spherical pores.

کلیدواژه ها:

Wire and arc additive manufacturing ، thin wall ، aluminum alloy ۲۳۱۹ ، microstructure ، mechanicalproperties