沉积电流对电弧增材制造316H/AFA钢微观组织和力学性能的影响OA

To achieve the preparation of an Aluminum-containing Austenitic Stainless Steel(AFA)layer on the surface of nuclear-grade 316H stainless steel substrates,wire arc additive manufacturing(WAAM)technology was employed.The study investigated the influence of deposition current on the formability,microstructure,and mechanical properties of the 316H/AFA steel composite components,achieving excellent single-pass multi-layer forming results through the optimization of process parameters.Three groups of deposition currents—117 A,133 A,and 148 A—were set,with a fixed weaving length of 2.25 mm.The optimal weaving width corresponding to each current was determined via single-pass single-layer ex-periments.The microstructure and phase composition of the components were characterized using metallographic micros-copy,EBSD,and XRD.Mechanical properties were tested via uniaxial tensile tests,and the ability of the AFA steel layer to form a high-temperature oxide film was verified.The results indicated that the optimal weaving widths corresponding to the three deposition currents were 11.0 mm,12.5 mm,and 13.5 mm,respectively.As the deposition current increased,both the layer width and layer height of the AFA deposit increased,with the layer width being more significantly affected by the cur-rent.The AFA deposit primarily consisted of columnar austenite grains growing along the deposition direction,and the grain length increased with both deposition height and current.The 316H/AFA steel fabricated by WAAM exhibited excellent me-chanical properties,with an elongation at break exceeding 40%,and superior interfacial bonding strength at the 316H/AFA interface.After oxidation in an air environment at 800℃for 120 hours,the AFA steel layer could spontaneously form a dense Al2O3 oxide film on its surface.This study provides significant experimental support for the process optimization,mi-crostructure and property control,and engineering application of AFA steel fabricated via arc additive manufacturing on 316H stainless steel surfaces.