Characteristics and Mechanism Analysis of Nano-sized TiO2 in Al2O3 Coating
GAO Xue-song1,2, HUANG Yin-hui1,2, TIAN Zong-jun1,2, LIU Zhi-dong1,2, SHEN Li-da1,2, WANG Dong-sheng2
1. Jiangsu Key Laboratory of Precision and MicroManufacturing Technology, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China; 2. College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanj
Abstract：The characteristics of the nano-sized TiO2 in the interface of laser-remelted ceramic material and NiCoCrAl bond coating were investigated by scanning electron microscope(SEM),energy dispersion spectrometer(EDS),and X-ray diffraction(XRD).The action mechanism of nano-sized TiO2 in the ceramic coating was studied as well.The results show that nano-TiO2 act as the medium that increases tenacity and conducts heat for ceramic material.With the micro-cracks increasing tenacity for ceramic material,the nano-sized TiO2 transferred the heat which was generated by high-energy laser beam to its surrounding Al2O3 simultaneous.Owing to its own melting,nano-sized TiO2 acted as bond phase,which made ceramic coating more compact.The nano-sized TiO2 in ceramic materials concentrated to the interface side and reacted with them,which implement chemical bonding between ceramic coating layer and bond coating.
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