Purpose: This paper aimed to propose a novel fused-coating-based additive manufacturing (FCAM); the study of key process parameters and mechanical tests are performed to determine the proper parameters when building metal components. Design/methodology/approach: Sn63Pb37 alloy is deposited in an induction heating furnace with a fused-coating nozzle to build metal parts on a copper-clad substrate. The process parameters including nozzle pressure, nozzle and substrate temperature and nozzle gap between substrate are analyzed and found to have great influence on parts quality. The mechanical property tests between the fused-coating and casting parts are performed in horizontal and vertical directions. Also, the optical microscopy images are used to ascertain under which conditions good bonding can be achieved. Findings: A FCAM method is proposed, and the exploration study about the manufacturing process is carried out. The critical parameters are analyzed, and microscopy images prove the suitable temperature range that requires to fabricate metal parts. The mechanical tests confirm that tensile strength of printing parts is improved by 20.4 and 11.9 per cent in horizontal and vertical direction than casting parts. The experimental results indicate that there is a close relationship between process parameters and mechanical properties. Originality/value: This paper proves that FCAM provides an alternative way to quickly make functional metal parts with good quality and flexibility compared with other additive manufacturing methods. Moreover, good mechanical property is achieved than conventional casting parts.

Microstructure and solute distribution have a significant impact on the mechanical properties of wire and arc additive manufacturing (WAAM) deposits. In this study, a multiscale model, consisting of a macroscopic finite element (FE) model and a microscopic phase field (PF) model, was used to predict the 2319 Al alloy microstructure evolution with epitaxial growth. Temperature fields, and the corresponding temperature gradient under the selected process parameters, were calculated by the FE model. Based on the results of macroscopic thermal simulation on the WAAM process, a PF model with a misorientation angle was employed to simulate the microstructure and competitive behaviors under the effect of epitaxial growth of grains. The dendrites with high misorientation angles experienced competitive growth and tended to be eliminated in the solidification process. The inclined dendrites are commonly hindered by other grains in front of the dendrite tip. Moreover, the solute enrichment near the solid/liquid interface reduced the driving force of solidification. The inclined angle of dendrites increased with the misorientation angle, and the solute distributions near the interface had similar patterns, but various concentrations, with different misorientation angles. Finally, metallographic experiments were conducted on the WAAM specimen to validate the morphology and size of the dendrites, and electron backscattered diffraction was used to indicate the preferred orientation of grains near the fusion line, proving the existence of epitaxial growth.