Wire-arc-additively manufactured Bi metallic structure: Mechanical properties and microstructural characterization

Abstract

In this investigation, the fabrication and mechanical properties of Bi metallic structure walls produced using wire-arc-additive manufacturing (WAAM) technique, employing stainless steel (SS) 316L and 304 filler wires, are examined. The findings reveal that SS 304 exhibits superior mechanical attributes compared to SS 316L, notably showcasing impressive tensile strength and exceptional ductility. Bi metallic structure, meticulously constructed using both SS 316L and SS 304 filler wires, effectively replicates these distinctive mechanical properties, rendering it highly desirable for application prioritizing mechanical performance. The observed enhancement in strength is attributed to variations in microstructure resulting from a complex thermal history. Microstructural and crystallographic analyses of Bi metallic structure are conducted using optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), electron backscattered diffraction spectroscopy (EBSD), and X-ray diffraction spectroscopy (XRD). Additionally, tensile strength (TS) of Bi metallic structure surpasses that of WAAM SS 316L by 3.95%. This comprehensive research not only elucidates the intricate process of material selection in additive manufacturing but also underscores the significant potential of Bi metallic structure in meeting the stringent demands of engineering applications requiring exceptional mechanical properties.