Abstract
As a typical intermetallic material, TiAl is inevitably difficult to process by conventional methods. Additive manufacturing (AM) has recently become a new option for making net-shape TiAl components. Among all AM methods, electron beam melting (EBM) shows the potential to make TiAl components with good mechanical properties and is used for low pressure turbine blades. The mechanical properties, including tensile and compression properties, fracture toughness, fatigue and creep properties of EBM TiAl are reviewed and compared to the conventionally fabricated alloys. Results show that the tensile strength of EBM alloys is higher than cast alloys, and other properties are comparable to the cast/forged alloys. The sensitivity of mechanical properties and microstructure to EBM processing parameters is presented. Issues including layered microstructure, anisotropy in mechanical properties, and fatigue failure from defects are also reviewed. Finally, some opportunities and challenges of EBM TiAl are identified.
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This work was financially supported by the Defense Industrial Technology Development Program (Grant No. JCKY2017205A002).
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Wei Chen Prof. Chen received his Ph.D. from Michigan State University, United States. Before joining AVIC Manufacturing Technology Institute in 2013, he was a postdoctoral fellow at the Materials Science and Technology Department of Oak Ridge National Lab. Prof. Chen is now the technical committee director of the Key Laboratory of Power Beam Processing. His research interest includes powder metallurgy, additive manufacturing, power beam welding, fatigue and creep behavior of Ti alloys. He has published over 50 research papers and 2 book chapters, and holds 6 patents. He also works on materials designing and received the R&D 100 Awards (2012) for his patent on nanocomposites used in the mining and drilling industry.
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Lin, Bc., Chen, W. Mechanical properties of TiAl fabricated by electron beam melting — A review. China Foundry 18, 307–316 (2021). https://doi.org/10.1007/s41230-021-1093-8
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DOI: https://doi.org/10.1007/s41230-021-1093-8