Abstract
Stray grains, the most serious casting defect, mainly occur in the platform because of the abrupt transition of the cross-section in the directional solidification of superalloy single-crystal blades. A new mould baffle technology based on 3D printing and gelcasting is proposed herein to reduce the formation of stray grains in the platform. The influence of the proposed mould baffle technology on the temperature field in the platform during solidification was investigated by simulation and experiment. The numerical simulation results indicate that the proposed mould baffle technology can effectively hinder the radiation and heat dissipation at the platform extremities, and therefore, reduce undercooling in the platform and the formation of stray grains during directional solidification. Casting trials of a hollow turbine blade were conducted using CMSX-4 superalloy. The trial results demonstrate the potential of the proposed approach for manufacturing single-crystal superalloy blades.
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This work was financially supported by the Industry-University Research Cooperation Project of Aero Engine Corporation of China (Grant No. HFZL2019CXY023), and the National Science and Technology Major Project (Grant No. 2017-VII-0008-0101).
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Zhong-liang Lu Professor and Doctoral Supervisor. Prof. Lu focuses his research on 3D printing principles, technology and application. He has presided over or participated in a series of projects funded by the National Natural Science Foundation of China, National Key R & D Program, and National Active & Standby Machine Project. To date, he has published more than 90 academic papers, three monographs on 3D printing, and possesses more than 50 invention patents of China. Prof. Lu is a Senior Member of Chinese Mechanical Engineering Society and a Senior Member of Additive Manufacturing and 3D Printing Institution.
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Liu, Zf., Miao, K., Lian, Wb. et al. Effect of mould baffle technology on stray grain formation in single crystal blades by integral fabrication based on 3D printing. China Foundry 18, 433–441 (2021). https://doi.org/10.1007/s41230-021-1073-z
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DOI: https://doi.org/10.1007/s41230-021-1073-z