An innovative way to fabricate γ-TiAl blades and their failure mechanisms under thermal shock. (October 2021)

• Record Type: Journal Article
• Authors: Gao, R.; Peng, H.; Guo, H.; Chen, B.
• Is Part Of: Scripta materialia. Number 203(2021)
• Publication Date: 2021-10
• Subjects: Titanium aluminides -- Intermetallic compounds -- Selective electron beam melting -- Additive manufacturing -- Thermal shock; Materials -- Periodicals; Metallurgy -- Periodicals; Metalen; Legeringen; Materiaalkunde; Metals, metalworking and machinery industries; Metals; Electronic journals; 620.11
• DOI: 10.1016/j.scriptamat.2021.114092
• Languages: English
• ISSNs: 1359-6462

Abstract

Abstract: The near-net-shape γ-TiAl blades were built by selective electron beam melting. As-fabricated material exhibits a good combination of microstructure homogeneity, tensile properties and thermal shock resistance at 700 °C owing to the optimised process parameters. The consistent and reliable approach to achieve this manufacturing success is elaborated. By performing thermal shock experiments at 900 °C, a new cracking mechanism has been identified. Through the post-mortem examinations, we reveal that such failure mode is most likely associated with the layer-by-layer strategy. Oxidation in conjunction with the surface topology is the underlying mechanism. Graphical abstract: Image, graphical abstract