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The steel wall measuring 120 mm in length and 210 mm in height was manufactured by wire and arc additive manufacturing (WAAM) using ER347 wire and gas metal arc welding (GMAW). The mechanical integrity and microstructure of the WAAM treated plate were examined. It was found that the steel plate was well formed, no clear boundaries between the layers were observed, and different thermal history leads to a variety of microstructures. The hardness of the WAAM-processed plate gradually varied from top to bottom and was between 203.5 HV and 248.2 HV. Microstructure of WAAM 347 consists of columnar dendrites and equiaxed dendrite in the multilayer deposition. The percent volume fraction of delta ferrite in the as-deposited WAAM plate was 4.2 and the predicted ferrite number from WRC-1992 diagram is 4.1. The mechanical properties of the welded parts were anisotropic; the sample at 45° orientation has a higher tensile strength compared to 0° and 90° orientation samples. The fractured tensile specimens in the as-deposited state were characterized by dimple-like structures revealing the ductile fracture. SEM line mapping confirms the presence of intermetallic compounds (NbC) in the WAAM 347 plate.

•Tribological behaviour of AISI 347 substrate and WAAM processed 347 samples at elevated temperatures have been studied.•WAAM processed 347 exhibits heterogeneous microstructure along the building direction.•The presence of Fe2O3and Fe3O4at elevated temperatures aided the formation of mechanically mixed composite oxide layer.•Wear mechanisms change from adhesive at 200 °C to mild oxidative at 600 °C where glaze oxide layers reduced the wear rate.