【作者】 王鲁斌； 王卫泽； 陈雨帆； 轩福贞；

【Author】 Lubin WANG;Weize WANG;Yufan CHEN;Fuzhen XUAN;Key Laboratory of Pressure Systems and Safety, Ministry of Education, East China University of Science and Technology;

【机构】 华东理工大学承压系统与安全教育部重点实验室；

【摘要】 涂层裂纹扩展路径观察与研究对于研究涂层的断裂机理具有重要作用。本研究对等离子喷涂硅灰石涂层在电镜下进行加载,并原位观察其裂纹扩展路径,之后计算得到涂层的断裂韧性,探讨涂层裂纹扩展对其断裂韧性的影响。结果表明裂纹的开裂与扩展过程呈现非连续,且涂层中原有孔隙对开裂过程具有一定的引导作用,但同时主应力方向对裂纹扩展路径亦有影响。涂层的断裂韧性低于相应块材的断裂韧性,涂层较低的断裂韧性与裂纹扩展通过涂层中的原有孔隙密切相关。更多还原

【Abstract】 Observation of the crack propagation in coatings is very important for the investigation on fracture mechanism. Fracture of plasma sprayed wollastonite coatings was observed in-situ using a Scanning Electron Microscope(SEM) during the Tapered Double Cantilever Beam(TDCB) specimens open. The fracture toughness was obtained subsequently. It is found that the initiation and crack propagation in coatings is discontinuous. The original pores in coatings can guide the cracking somewhat. The local principal stress also can influence the cracking propagation path. The lower fracture toughness of coatings, compared with the corresponding sintered materials, is partially affected by the crack propagating through the existing pores in coatings.更多还原