J. Mater. Sci. Technol. ›› 2025, Vol. 209: 64-78.DOI: 10.1016/j.jmst.2024.04.076

• Research Article • Previous Articles     Next Articles

Enhanced 3D printing and crack control in melt-grown eutectic ceramic composites with high-entropy alloy doping

Zhonglin Shena,b, Haijun Sua,c,*, Minghui Yua, Yinuo Guoa,b, Yuan Liua, Hao Jianga, Xiang Lia, Dong Donga, Peixin Yanga, Jiatong Yaoa, Min Guoa, Zhuo Zhanga, Wei Rend   

  1. aState Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an 710072, China;
    bDepartment of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117575, Singapore;
    cResearch & Development Institute of Northwestern Polytechnical University in Shenzhen, Shenzhen 518057, China;
    dState Key Laboratory of Advanced Special Steel, Shanghai Key Laboratory of High Temperature Superconductors, International Center for Quantum and Molecular Structures, Shanghai University, Shanghai 200444, China
  • Received:2024-03-18 Revised:2024-04-23 Accepted:2024-04-30 Published:2025-02-20 Online:2024-05-27
  • Contact: *State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072, China. E-mail address: shjnpu@nwpu.edu.cn (H. Su)

Abstract: As a 3D printing method, laser powder bed fusion (LPBF) technology has been extensively proven to offer significant advantages in fabricating complex structured specimens, achieving ultra-fine microstructures, and enhancing performances. In the domain of manufacturing melt-grown oxide ceramics, it encounters substantial challenges in suppressing crack defects during the rapid solidification process. The strategic integration of high entropy alloys (HEA), leveraging the significant ductility and toughness into ceramic powders represents a major innovation in overcoming the obstacles. The ingenious doping of HEA particles preserves the eutectic microstructures of the Al2O3/GdAlO3(GAP)/ZrO2 ceramic composite. The high damage tolerance of the HEA alloy under high strain rates enables the absorption of crack energy and alleviation of internal stresses during LPBF, effectively reducing crack initiation and growth. Due to increased curvature forces and intense Marangoni convection at the top of the molt pool, particle collision intensifies, leading to the tendency of HEA particles to agglomerate at the upper part of the molt pool. However, this phenomenon can be effectively alleviated in the remelting process of subsequent layer deposition. Furthermore, a portion of the HEA particles partially dissolves and sinks into the molten pool, acting as heterogeneous nucleation particles, inducing the formation of equiaxed eutectic and leading primary phase nucleation. Some HEA particles diffuse into the lamellar ternary eutectic structures, further promoting the refinement of eutectic microstructures due to increased undercooling. The innovative doping of HEA particles has effectively facilitated the fabrication of turbine-structured, conical, and cylindrical ternary eutectic ceramic composite specimens with diameters of about 70 mm, demonstrating significant developmental potential in the field of ceramic composite manufacturing.

Key words: Laser powder bed fusion, Eutectic ceramic composite, High entropy alloy doping