Abstract
Selective laser melting (SLM) is an ideal method to directly fabricate products with high geometrical complexity. With low density and good corrosion resistance, aluminum alloys are widely used as important structural materials. Microstructures and mechanical properties of SLMed aluminum alloys have been recently widely studied. Corrosion behavior as a vital concern during the service of SLMed aluminum alloy parts has also drawn many attentions. Previous studies have found that SLM-processed aluminum alloys exhibit better corrosion resistance compared to the casted and wrought counterparts for both Al-Si alloys and high strength 2xxx Al alloys, which is mainly due to the unique microstructure features of SLMed Al alloys. For Al-Si alloys, with different shapes of Si networks, the different building planes show discrepant corrosion behaviors. Owing to the rougher surface with relatively larger numbers of defects, the as-printed surface is vulnerable to corrosion than the polished. Heat treatment has a negative effect on corrosion resistance due to the breakup of Si networks. The microstructure features correlated with the corrosion behaviors were also reviewed in this paper. Some suggestions on the future study of corrosion behaviors of SLMed Al alloys were put forward.
Highlights
Growing attention has been paid to 3D printing due to the significant advantages it offers in manufacturing products with complex structures without extra machining processes [1,2,3]
In order to further understand the research progress of Selective laser melting (SLM) produced aluminum alloys in corrosion resistance, this paper mainly describes the influence of post heat treatment on microstructure evolution and corrosion resistance of SLM-produced Al-Si alloys
Gu and Zhang et al found that the results are in accordance with weight lo sts and corrosion morphology, the untreated sample has the highest corrosion potential and th owest corrosion current density, while the 300 °C heat treated sample has the worst polarizatio curves of heat treated SLM AlSi10Mg is tested in 0.1 M NaCl solution, Rubben et al thought that the similar anodic polarization curves of tested samples are not obvious enough to confirm the difference of corrosion resistance.[66]
Summary
Growing attention has been paid to 3D printing due to the significant advantages it offers in manufacturing products with complex structures without extra machining processes [1,2,3]. Due to the non-equilibrium state after SLM process, an post of the large temperature gradient, the sizes of cellular structures gradually grow with the increasing heat treatment that is applied to the adjustment of mechanical properties has a significant influence on distance away from the center of the melt pool [51,52,53]. The corrosion behaviors vary with the sizes of cellular morphology, such as the melt pool borders, having the largest cellular structure among the printed surface [66,67,68] The working places, such as in the wet environment or corrosive seawater environment that facilitate corrosion reaction, have a significantly negative impact on the corrosion resistance of SLM alloys [69]. The summary and outlook of SLM aluminum alloys on corrosion resistance study is described in the last part
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
