J. Mater. Sci. Technol. ›› 2025, Vol. 208: 120-131.DOI: 10.1016/j.jmst.2024.04.060

• Research Article • Previous Articles     Next Articles

Reinforcing and toughening mechanism of the in-situ metastable nanostructured alumina-titanium oxide composite coating

Yu-duo Maa,b, Yong Yanga,*, Li-wu Yuana, Wei Tianc, Hongjian Zhaoa   

  1. aHebei Key Laboratory of New Functional Materials, School of Materials Science and Engineering, State Key Laboratory of Reliability and Intelligence of Electrical Equipment, Hebei University of Technology, Tianjin 300401, China;
    bHebei Huabei Diesel Engine Co., Ltd., Shijiazhuang 050081, China;
    cAECC Sichuan Gas Turbine Establishment, Chengdu 610500, China
  • Received:2023-12-01 Revised:2024-04-08 Accepted:2024-04-23 Published:2025-02-10 Online:2024-05-17
  • Contact: * E-mail address: yangyonghebut@163.com (Y. Yang).

Abstract: High porosity and high brittleness are the main reasons that limit the long-term service life of the alumina-titanium oxide composite coating. Herein, a metastable nanostructured alumina-titanium oxide composite coating with high density and high properties was synthesized by plasma spraying of TiO2-Al composite powder. The main phases of the metastable nanostructured alumina-titanium oxide were γ-Al2O3, TiO and AlTiO2. The coating, as prepared, contains various metastable microstructures, such as fine-grained, intra-/inter-granular, and "self-locking" microstructures. These metastable microstructures are important for the improvement of hardness and toughness of the coating. Compared with other alumina-based composite coatings, the metastable nanostructured alumina-titanium oxide composite coating showed the most impressive overall performance. The reinforcing and toughening mechanism of the metastable alumina-titanium oxide composite coating included fine grain strengthening and self-toughening of the metastable microstructure.

Key words: In-situ synthesis, Metastable oxide, Nanostructured coating, Reinforcing and toughening mechanism