Additive Manufacturing of Refractory Metallic Materials: Poster Session
Sponsored by: TMS Materials Processing and Manufacturing Division, TMS: Additive Manufacturing Committee
Program Organizers: Antonio Ramirez, Ohio State University; Jeffrey Sowards, NASA Marshall Space Flight Center; Omar Mireles, NASA; Eric Lass, University of Tennessee-Knoxville; Faramarz Zarandi, RTX Corporation; Matthew Osborne, Global Advanced Metals; Joao Oliveira, Faculdade Ciencias Tecnologias
Monday 5:30 PM
March 20, 2023
Room: Exhibit Hall G
Location: SDCC
Session Chair: Joao Pedro Oliveira, Universidade NOVA de Lisboa; Eric A. Lass , University of Tennessee-Knoxville
A-38: Development and Assessment of a Novel TiVNbMo-based Refractory High Entropy Alloy Manufactured by Laser Powder Bed Fusion for High Temperature Applications: Lucy Farquhar1; Lova Chechik1; Alexander Goodall1; Abdallah Reza2; Felix Hofmann2; Iain Todd1; Russell Goodall1; 1University of Sheffield; 2University of Oxford
In recent years, novel alloys have been designed specifically for Additive Manufacturing (AM), optimising microstructures and mechanical properties. Refractory High entropy alloys (HEAs) have also been shown to exhibit stable microstructures and good mechanical properties at high temperatures when manufactured using AM.In this work an assessment of weldability is proposed to ascertain the suitability of novel refractory HEAs for AM, using small arc-melted samples, prior to any powder manufacture. This results in a method to assess if an alloy will be able to be manufactured by AM without cracking, before the costly step of producing powder and completing the AM process itself. Weld Tracks and modelling were completed on known HEAs as well as novel refractory HEAs, to ascertain crack susceptibility. The novel TiVNbMo-based HEA resulting from this modelling, is then successfully manufactured using laser powder bed fusion.
A-39: Development of Molybdenum Parts for High Temperature Applications with Laser Directed Energy Deposition Additive Manufacturing: Andrew Hutchinson1; 1Georgia Institute of Technology
Refractory metals such as Molybdenum are well known for their use in high temperature applications. However, challenges in manufacturability hinder the implementation of these otherwise extremely useful materials. With the emergence and maturation of laser directed energy deposition additive manufacturing technologies, Molybdenum stands to benefit greatly. This work demonstrates the use of such methods to create dense Molybdenum parts efficiently. Furthermore, parameter spaces and process improvements are investigated to create large, printed parts. Comparison is to be made between conventionally manufactured parts and these additively manufactured parts to determine the most effective strategies in the process parameter space to replicate and improve upon the manufacturability of large Molybdenum parts.
A-85: Directed Energy Deposition of Niobium and Related Alloys: Sucharita Banerjee1; Advika Chesetti2; Mohan Sai Kiran Nartu2; Venkata Mani Krishna Karri2; Sameehan Joshi2; Eric Taleff1; Narendra Dahotre2; Rajarshi Banerjee2; 1University of Texas at Austin; 2University of North Texas
Despite substantial interest in the additive manufacturing (AM) of refractory metals and alloys, data from experimental investigations in this field remain quite limited. This study presents new data on specimens of commercial-purity Nb and the Nb-based alloy C103 produced using laser-engineered net shaping (LENS), a directed energy deposition process that uses blown powders. Process parameters that directly impact the input energy density, such as laser power and scanning speed, were varied to measure their influences on the microstructure and microhardness of LENS deposits. The degree of porosity and the size, morphology, and aspect ratio of grains were measured and analyzed as a function of the process parameters. Details of the substructure within the grains, such as subgrain boundaries, were also investigated. The tensile properties of selected specimen builds were measured. The results of these experiments and analyses will be discussed and rationalized in this presentation.
Interfacial Microstructures between Mo and Stainless Steel Fabricated by Directed Energy Deposition for High Temperature Service Applications: Sumin Lee1; Seunghyun Lee1; Jaeyoon Bae1; Sanghoon Noh1; 1Pukyong National University
The austenitic stainless steel is one of the key structural materials in various industrial fields such as marine, aerospace, thermal power, and nuclear/fusion applications because of its excellent mechanical property and corrosion resistances. Nowadays, additional fabrication processes to enhance the anti-environmental resistance of stainless steel were being required. In present study, Mo layer was fabricated on austenitic stainless steel and interfacial microstructures were investigated. A directed energy deposition process was successfully employed to fabricate a novel Mo coated layer on the surface of the stainless steel substrates. Microstructural observations revealed that DED-Mo has fine grains aligned toward a process direction, and favorable interface without critical micro-cracks and brittle intermetallic layer. This result showed that DED process is considered to be one of the promising ways to join dissimilar materials between refractory metal and structural steels, which could avoid the formation of an interfacial intermetallic layer.
A-40: Investigation into Wire Arc Additive Manufacturing Titanium-Zirconium-Molybdenum (TZM) Alloy: Saiful Islam1; DuckBong Kim1; 1Tennessee Tech University
Titanium-zirconium-molybdenum (TZM) has extraordinary physicochemical properties, making it ideal for usage in extreme environmental applications. Wire + arc additive manufacturing has several advantages, including high deposition rate, energy efficiency, and cost-effective manufacturing of large components. In this study, we comprehensively investigate the relationships among process, microstructures, mechanical properties, and defects of WAAM TZM thin-walls with four heat input conditions: 180A, 200A, 220A, and 240A. Columnar grains were generated with strong texture along the build direction, and carbide precipitates were found uniformly distributed in the Mo matrix. Multi-scale pores and cracks were present in the microstructures. The average microhardness values for the deposits ranged from 188.5 to 193.5 hardness scales of Vickers. The highest yield strength, 195 MPa, was found in the 200A heat input condition. The primary fracture mode was identified as a brittle transgranular. The largest area fraction of porosity was calculated 2.04% in the 240A deposit.