表面技术2026，Vol.55Issue(1)：198-207,10.DOI:10.16490/j.cnki.issn.1001-3660.2026.01.017
双层结构黏结层热生长氧化物近指数生长机理研究
Near-exponential Growth Mechanism of Thermally Grown Oxide in Double Bond Coat
摘要
Abstract
Thermally grown oxide(TGO)growth is a critical failure mechanism of thermal barrier coatings(TBCs)for hot-section component in gas turbines.In our previous work,TBCs with double bond coat was developed,and TGO exhibited a roughly exponential growth with the thermal exposure duration.As a result,the durability of the TBCs is improved by about 100％.However,this slow growth mechanism of TGO is still not clear yet.This study aims to address the roughly exponential growth of TGO on the double bond coat,according to TGO evolution and the synergistic mechanism of stress buffering and diffusion barriers.The double bond coat was fabricated via two thermal spraying technologies.The atmospheric plasma spraying(APS)was used to deposit a porous bond coat(Por-BC,(50±5)μm,(12±3)％porosity)by Ni-23Co-20Cr-8.5Al-5.0Ta-0.6Y powder.The high-velocity oxygen fuel(HVOF)spraying then was used to prepare a dense oxidized bond coat(Oxi-BC,100 μm thick)on Por-BC(15％Al2O3 dispersed in Oxi-BC).40 μm-thick 8％Y2O3-ZrO2(YSZ)topcoat was deposited by APS with hollow spherical YSZ powder.Samples underwent pre-oxidation(Ar atmosphere,<10 μmol/mol O2,from 1 000℃/4 h to 1 080℃/4 h,furnace cooling)and high-temperature oxidation at 1 000℃in static air for 5 h,20 h,50 h,100 h,200 h,and 500 h.TGO morphology/thickness was observed via SEM(10 random regions averaged).In-plane compressive stress in TGO was evaluated via Raman spectroscopy(514 nm laser,R2 peak shift).Results showed that the double bond coat had a gradient coefficient of thermal expansion(CTE):the Por-BC(adjacent to the Inconel 738 substrate)had a CTE of 12.0×10-6 K-1,and the Oxi-BC(near the YSZ topcoat)had a CTE of 11.6×10-6 K-1,which could reduce thermal mismatch stress between the substrate and the topcoat.Therefore,the double bond coat could significantly improve the durability of TBCs because of the decrease of the interior stress.TGO thickness on the double bond coat was about(1.26±0.11)μm and(1.71±0.17)μm,when the thermal exposure time was 100 h and 500 h,respectively.In comparison,the TGO thickness in traditional TBCs was about(1.53±0.19)μm and(6.32±0.31)μm,respectively,when the thermal exposure time was 100 h and 500 h.Raman analysis showed the compressive stress in TGO on the double bond coat was about-1.75 GPa(5 h),-1.93 GPa(20 h),-2.03 GPa(50 h),-2.07 GPa(100 h),-2.28 GPa(500 h),which was over 50％lower than that in traditional TBCs.SEM at 200 h showed β-NiAl phases(Al-rich)adjacent to TGO in the double bond coat(no Al-depleted zone),while traditional bond coat had β-NiAl 10 μm from TGO with a clear Al-depleted zone(severe Al diffusion).The near-exponential slow TGO growth on the double bond coat was resulted from two synergistic effects.Firstly,gradient CTE in TBCs alleviated thermomechanical stress,reducing in-plane compressive stress in TGO by about 50％.Subsequently,the number of micro-flaws,such as interface separations and micro-cracks in TGO in new TBCs,was significantly lower than that in TGO in in traditional TBCs.Secondly,a dense,crack-free TGO inhibited O/Al diffusion,avoiding the rapid oxidation.关键词
热障涂层/双层黏结层/梯度热膨胀系数/高温氧化/TGO生长机理Key words
thermal barrier coatings/double bond coat/gradient thermal expansion coefficient/high temperature oxidation/TGO growth mechanism分类
矿业与冶金引用本文复制引用
王飞,董会,伊静,冯玉坤..双层结构黏结层热生长氧化物近指数生长机理研究[J].表面技术,2026,55(1):198-207,10.基金项目
国家自然科学基金(52474081) （52474081）
陕西省自然学科基金重点项目-关键核心技术攻关(2024CY-GJHX-39) （2024CY-GJHX-39）
西安市创新生态优化专项计划(科学家+工程师队伍建设项目,24KGDW0039) （科学家+工程师队伍建设项目,24KGDW0039）
西安石油大学研究生创新基金(YCS23211007) National Natural Science Foundation of China(52474081) （YCS23211007）
Key Project of Natural Science Foundation of Shaanxi Province-Critical Core Technology Research(2024CY-GJHX-39) （2024CY-GJHX-39）
The Xi'an Innovation Ecology Optimization Special Program Project(Scientists+Engineers Workforce Building Program,24KGDW0039) （Scientists+Engineers Workforce Building Program,24KGDW0039）
Graduate Innovation Fund Project of Xi'an Shiyou University(YCS23211007) （YCS23211007）
