Effect of Scanning Speed on Microstructure and Mechanical Properties of Al2O3–ZrO2 Gradient Ceramics Fabricated by Laser Directed Energy Deposition
WU Dongjiang1, YU Xuexin1, LÜ Weijie1, SHI Jing2, YOU Zhulin3, MA Guangyi1, NIU Fangyong1
1. State Key Laboratory of High-Performance Precision Manufacturing, Dalian University of Technology, Dalian 116024, China;
2. Kingsemi Limited Liability Company, Shenyang 110169, China;
3. Unit 95939 of the Chinese People’s Liberation Army, Cangzhou 061736, China
Functional gradient ceramics (FGC) are novel ceramic materials that integrate structure and function, enabling the material’s composition and properties to continuously vary as needed. FGCs have broad application prospects in fields such as aerospace and biomedical engineering. Laser directed energy deposition (LDED) technique overcomes the obvious limitations of conventional preparation methods in terms of sintering deformation and transition interfaces, which achieves regionally controllable properties of FGCs. However, optimizing the performance of different components simultaneously through constant parameter fabrication is not feasible. Therefore, the effect of scanning speed on the composite ceramic materials with various proportions in Al2O3–ZrO2gradient ceramics was investigated. By determining the optimal scanning speed for each composite ceramic, the optimal fabrication of Al2O3–ZrO2 gradient ceramics with variable parameters was achieved. The results show that under low scanning speed conditions (200 mm/min, 300 mm/min), the α-Al2O3 columnar crystals exhibit obvious growth orientation tendency, and macroscopic cracks are apparent in composite ceramics with high ZrO2content. The gradual increase of scanning speed helps to reduce the grain size and thus improve the mechanical properties of the fabricated sample, but too high scanning speed leads to more internal defects and decreases the performance. The variable scanning speed fabricating process effectively suppresses the macroscopic cracks with high ZrO2content in the gradient region. In addition, the macro and micro cracking defects at the bonding interface of Al2O3–ZrO2gradient ceramics with constant parameters are improved. The flexural strength at the transition interface of optimally manufactured Al2O3–ZrO2 gradient ceramics is improved by 21.37%.
吴东江,于学鑫,吕伟杰,石晶,由竹琳,马广义,牛方勇. 扫描速度对激光定向能量沉积Al2O3–ZrO2梯度陶瓷微观组织及力学性能的影响[J]. 航空制造技术, 2023, 66(16): 30-37.
WU Dongjiang, YU Xuexin, Lü Weijie, SHI Jing, YOU Zhulin, MA Guangyi, NIU Fangyong. Effect of Scanning Speed on Microstructure and Mechanical Properties of Al2O3–ZrO2 Gradient Ceramics Fabricated by Laser Directed Energy Deposition[J]. Aeronautical Manufacturing Technology, 2023, 66(16): 30-37.