表面技术2025，Vol.54Issue(7)：212-224,13.DOI:10.16490/j.cnki.issn.1001-3660.2025.07.018
"砖-泥"结构陶瓷封严涂层横向裂纹扩展抑制机理
Inhibition Mechanism of Transverse Crack Propagation in Ceramic Sealing Coating with"Brick-Mud"Structure
摘要
Abstract
As one of the core technologies of aero-engine,ceramic high-temperature seal coating technology has been widely applied to make aerospace materials.Such coatings face a bottleneck of early spalling failure under thermal cycle conditions.The work aims to take"brick-mud"structured coating as the research object and explore the effect of pore size on the thermal cycle performance of ceramic"brick-mud"structured seal coatings based on the pore"suction"effect,so as to optimize the microstructure of the coating and provide a reference for solving early spalling failure.Finite Element Simulation is used to establish"mud"layer models with different pore radii(0,1,2,3,4 µm).The stress field and transverse crack propagation behavior of the"mud"layer models with different pore sizes under thermal cycle conditions are analyzed.The introduction of pores in the"mud'layer has the functions of"stress redistribution"and"stress concentration".The stress concentration position in the"mud"layer with pores shifts from the"brick-mud"interface in the pore-free state to the vicinity of the pores.Additionally,the stress field action area significantly decreases.Compared with the original"mud"layer,the maximum tensile stress(σ22 max)and the maximum shear stress(σ12 max)of the"mud"layer model with pores significantly increase.Meanwhile,the transverse crack propagation length in the"mud"layer models with pore radii of 1,2,3,and 4 µm decreases by 84.3%,54.8%,51.5%,and 59.5%,respectively.At the same time,the energy dissipation level decreases by 98.5%,62.7%,91.1%,and 86.9%,respectively.When the pore radius increases from 0 µm to 1 µm,the reduction in transverse crack length is the most significant.Similarly,the reduction in energy dissipation is also the most significant.Because of the"stress redistribution"and"stress concentration",the pores exhibit a"crack attraction"effect during thermal cycle.As a result,the crack propagation direction is changed and the continuous crack propagation is inhibited.The stress field of the"mud"layer model with pores is mainly affected by the coupling effect of three factors,namely,"brick"layer pores,"mud"layer pore radius,and the thermal expansion and contraction of porous materials.As a result,as the pore radius increases,the crack propagation path in the model with pores exhibits distinct evolution patterns.Among them,small pores with a radius of 1 µm have the weakest stress field for transverse crack propagation driven by thermal cycle,which makes the T1 model have the shortest transverse crack propagation path and the lowest energy dissipation level.关键词
"砖-泥"结构/热循环失效/孔隙"吸引"效应/应力再分布/应力集中/横向裂纹扩展Key words
"brick-mud"structure/thermal cycling failure/pore"suction"effect/stress redistribution/stress concentration/transverse crack propagation引用本文复制引用
程涛涛,吴治兵,蒋家有于,曹雨函,马梁,张莹.."砖-泥"结构陶瓷封严涂层横向裂纹扩展抑制机理[J].表面技术,2025,54(7):212-224,13.基金项目
中央高校基本科研业务费自然科学重点项目(3122025081) Natural Science Key Project of Basic Research Funds of Central Universities(3122025081) （3122025081）
