In the review paper, "Processing, Defect Formation, Microstructure, and Mechanical Properties of Additively Manufactured Refractory Metals", authors from University of Science and Technology Beijing, Xinjiang Institute of Engineering, and China United Gas Turbine Technology Co. present a comprehensive and in-depth coverage of processing, microstructure, mechanical properties and strengthening mechanisms of refractory metals and alloys made using three metal additive manufacturing technologies: laser powder bed fusion (L-PBF), laser-directed energy deposition (L-DED), and electron beam selective melting (EBSM). As every materials engineer knows, refractory metals such as tungsten, molybdenum, tantalum, and a few others have very high melting points (2100-3500 C), high strength at elevated temperatures, and excellent creep and corrosion resistance. These metals and their alloys commonly are made using traditional powder metallurgy and melting techniques. Synthesizing these alloys using rapid, nonequilibrium melting and solidification technologies via AM facilitates creation of unique structural features for properties, such as gradient and periodically varying microstructures. This design flexibility potentially could further accelerate usage of refractory alloys in nuclear energy, electronics, chemical, aerospace and defense applications. The authors identify issues and challenges in applying AM to refractory metal design and production and prognosticate developments going forward. They also highlight the role of machine learning in AM of refractory alloys to predict product quality, manage defects, and optimize process parameters. The authors don't just warehouse the literature information; they present a thorough and critical analysis of the literature and offer fresh technical insights to educate and inspire the reader.
This review article is free to read here now through November 30.
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Rajiv Asthana
Professor
UNIVERSITY WISCONSIN-STOUT
Menomonie WI
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