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Additive manufacturing (AM) is a highly advanced manufacturing technology that involves metal layers deposition in order to increase the efficiency of component production and costs reduction. Current study includes examining the effects of adding aluminium as an additional alloying element to austenitic stainless-steel SS 309L. Metal Inert Gas (MIG) welding apparatus was used as a heat source for the deposition of the steel in the Wire Arc Additive manufacturing method. Simultaneously during the building process, three different percentages (0, 2.5%, and 5%) of an external aluminium alloy 4043 (E4043) cold wire was introduced into the fusion zone. The focus of the study is to highlight the influence of adding E4043 on the microstructure and mechanical properties of additively manufactured SS309L. For the microstructural investigations, optical microscopy and scanning electron microscopy (SEM) were used, whereas a Vickers microhardness test was used to investigate the effect of these additions on the local mechanical properties. On the other hand, the mechanical behavior of the deposited parts was examined using tensile test. The results of the study demonstrated that the addition of the aluminum alloy is significantly affect the mechanical properties of the deposited portions. The quantity of the added aluminum is discovered to have an influence on the microstructure, hardness, and tensile strength. Moreover, the homogenizing thermal treatment improved the samples' microstructure and overall properties. The found results highlights the importance of considering double wire feeding in additive manufacturing processes to reach the desired microstructural and mechanical properties in the final products. [ABSTRACT FROM AUTHOR]

• Ti6Al4V/AA2024 alloy component is fabricated based on interweaving structure. • The compressive shear strength of the Ti6Al4V/AA2024 alloy component is 86.1 MPa. • The Ti6Al4V/AA2024 alloy component's shear strength is 79 % of as-deposited AA2024. • The fracture occurs in the interweaving layer in shear tests. The presence of brittle intermetallic compounds (IMCs) can easily lead to cracks at the interface of titanium/aluminum alloy components. A novel interweaving structure was proposed and a Ti6Al4V/AA2024 dissimilar alloy component was prepared. The interlocking between Ti6Al4V and AA2024 mitigates the adverse effects of brittle IMCs on the Ti/Al interface, while the interweaving of Ti6Al4V and AA2024 avoids the generation of continuous IMCs. The average compressive shear strength of the Ti6Al4V/AA2024 alloy component is 86.1 MPa, which is 79 % of that of as-deposited AA2024. The fracture occurred in the interweaving layer in shear tests. [ABSTRACT FROM AUTHOR]

Many additively manufactured alloys exhibit higher strengths than compositionally identical alloys processed via conventional processing routes. However, this enhancement is not consistently observed in 7xxx series aluminum alloys. These alloys present two complications when printed via Laser Powder Bed Fusion (LPBF): significant evaporation of strengthening elements from the melt pool and hot cracking during solidification. To address these issues, we introduce two modifications to the feedstock powder: (i) we increase the concentration of alloying constituents to counteract evaporation during printing, and (ii) we disperse TiC nanoparticles within the feedstock powder to promote heterogeneous nucleation and limit grain growth, thus avoiding hot cracking and improving strength. Relationships between the evaporation of alloying elements and laser energy density are quantified experimentally using inductively-coupled-plasma mass-spectrometry and are well captured by simple analytical models. The microstructures in as-printed and heat-treated conditions are characterized using X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Printing parameters have been optimized to attain minimum porosity, resulting in tensile strengths up to 650 MPa, which are in good agreement with predictions from classic models of strengthening mechanisms. [ABSTRACT FROM AUTHOR]

Nickel aluminium bronze alloy specimens were produced using laser powder bed fusion (LPBF) and subjected to heat treatment to understand their corrosion behaviour when exposed to a 3.5 wt% NaCl solution. Electrochemical analysis, including impedance spectroscopy and polarization curves, was performed to characterize the samples after 30 days of immersion. The findings reveal that the as-built samples exhibit superior corrosion resistance compared to the heat-treated samples, primarily attributed to the lower presence of intermetallic phases, which hinder the alloy's passivation process. • NAB produced via AM exhibit lower corrosion current densities than thr heat-treated. • The microstructure and corrosion behavior of NAB is significantly influenced by fabrication methods and heat treatment. [ABSTRACT FROM AUTHOR]