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In water-soluble binder systems, polyethylene glycol (PEG) and polymethylmethacrylate (PMMA) are often used as primary and secondary components. The PEG/PMMA binder system is clean and environmentally friendly, but the discrepancy between the crystallization temperature of PEG and the glass transition temperature of PMMA leads to the generation of pores in the feedstock. The solidification pores have an adverse impact on the final mechanical properties of the samples. Polyvinylpyrrolidone (PVP), as a crystallization inhibitor, can inhibit the formation of porosity. In this study, spherical titanium powder with a diameter of less than 45 μm was used as metal powder; the binder system consisted of PEG, PMMA and SA. Different increments of PVP (0, 10%, 20%, 30 wt.%) were added to the PEG/PMMA binder system. The uniformity of the feedstock and the open channels generated after debinding were observed using SEM. The pores’ condition before and after debinding was studied using Micro CT, and the mechanical properties of the samples were also detected. By comparing the macroscopic and microscopic morphologies of the injected samples and mechanical properties of the sintered samples, it was found that a PVP content of 20 wt.% resulted in the best properties.

In this work, an AA5183 alloy plate was successfully deposited by low-power cold metal transfer technology. The forming defects, microstructural characteristics, and mechanical properties were investigated. The results show that the number of defects increases gradually along the building direction of the deposited plate. X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, electron probe microanalysis, electron backscatter diffraction, and transmission electron microscopy were employed to study the distribution of alloying elements, deposited microstructural characteristics, and the crystal structure of intermetallic compounds in the Al alloy plate. The tensile samples perpendicular to the building direction presented greater tensile strength and superior plasticity compared to those parallel to the deposition direction. The average UTS was 327 ± 0.65 MPa and the average EL was 30.6 ± 2.0%. The UTS of conventionally forged 5083-H32 (Al-Mg4.5) alloy is 324 MPa; the UTS of extruded 5083-H116 (Al-Mg4.5) alloy is 305 MPa. Further, the strength of our prepared plate reaches the value needed for industrial applications of the 5083 Al alloy. The differences in the strength and plasticity of the samples assessed under multiple sampling methods were analyzed based on a synergistic strength–ductility mechanism.