Chen Guofeng

TL;DR: In this paper, the authors introduce the state-of-the-art research progress in length scale-related fatigue performance of conventionally-fabricated metals evaluated by miniature specimens and propose a potential roadmap to establish a data-driven evaluation platform based on a large number of miniature specimen-based experiment data, theoretical computations and the big data analysis with machine learning.

Abstract: Voids are always unavoidably introduced into metals fabricated by selective laser melting (SLM), and thus greatly degrade fatigue performance of metals. Such a fatal weakness strongly limits the application of SLM‐fabricated metals to load‐bearing structural components for the long‐term service. Here, the authors found that fatigue strength of SLM‐fabricated Inconel 718 is significantly improved after the proper heat treatment route not only due to the elimination of Laves phases and the precipitation of γ″/γ′ strengthening phases, but also the appearance of ultrafine‐scale acicular δ phases, which effectively suppressed the degraded effect of voids. The finding may provide a potential strategy to enhance fatigue strength of SLM‐fabricated materials by tailoring heat‐treatment route.

TL;DR: In this article, the effect of microstructure and surface roughness on the oxidation behavior of the SLM-fabricated, as-cast, and as-forged Inconel 718 specimens was examined.

TL;DR: In this article, a method for improving the quality of the inner surface of a 3D printed part is proposed, where the surface voids and tiny pits of the surface of the printed part with an internal groove structure can be filled with materials.