Invited Speaker
Prof. Wenzhi Huang (Research Fellow)
Science and Technology on Advanced Ceramic Fibers and Composites Laboratory, College of Aerospace Science and Engineering, National University of Defense Technology
E-mail: huangwenzhi_kd@163.com
Title: Optimization Strategies for Enhancing CMAS Corrosion resistance in YSZ Coatings
Profile:
Huang Wenzhi, professor and doctoral supervisor, is the director of a key laboratory of National University of Defense Technology. His research specializes in the fundamental and applied engineering of high-temperature functional ceramic coatings, including thermal barrier coatings (TBCs) and high-temperature microwave-absorbing coatings. He is a member of a military high-level scientific innovation team and a recipient of Hunan Natural Science Fund for distinguished young scholars. Significant research advancements have been achieved in the design, fabrication, mechanical evaluation, and engineering application of high-temperature special functional ceramic coatings, including thermal barrier coatings (TBCs) and high-temperature microwave-absorbing coatings. Multiple coating materials successfully applied in national defense equipment systems. His honors include the NUDT major scientific advancement award, China outstanding patent award, and provincial academic achievement scond prize. He has published over 60 articles, secured over 40 authorized invention patents, and published 2 monographs.
Abstract:
Thermal barrier coatings (TBCs), as a ceramic coating deposited on metallic hot-section components of aeroengines, significantly enhance operational temperature and oxidation resistance. However, corrosion induced by molten environmental deposits (CaO-MgO-Al₂O₃-SiO₂, CMAS) severely threate the service life of the aeroengine. To address the insufficient CMAS resistance of conventional 8 wt% Y₂O₃-stabilized ZrO₂ (8YSZ) coatings, this study proposes an innovative optimization strategy combining second-phase composite modification and high-concentration doping modification. LaPO₄-YSZ composite coatings and 56YSZ coatings with elevated Y₂O₃ doping were fabricated via atmospheric plasma spraying, followed by systematic investigation of their corrosion behaviors and mechanisms at different temperatures. Results reveal that the aggregation of second-phase particles at YSZ grain boundaries forms weak interfaces, thereby enhancing the fracture toughness. Simultaneously, the second phase rapidly reacts with CMAS to generate a continuous and dense apatite-based barrier layer, effectively inhibiting CMAS infiltration. In 56YSZ coatings, sufficient Y³⁺ ions react with CMAS to form an apatite layer, achieving corrosion self-inhibition. This work reveals that the enhancement of CMAS resistance originates from the regulation of interfacial reaction pathways, where rapid crystallization of barrier layers blocks the penetration of molten salt. These findings provide critical insights for the composition design and performance optimization of next-generation TBCs.