Experimental and numerical investigation on the thermal and mechanical behaviours of thermal barrier coatings exposed to CMAS corrosion  

作　　者：Dongxu LI Peng JIANG Renheng GAO Fan SUN Xiaochao JIN Xueling FAN 

机构地区：[1]State Key Laboratory for Strength and Vibration of Mechanical Structures,School of Aerospace Engineering,Xi’an Jiaotong University,Xi’an 710049,China [2]AEEC Sichuan Gas Turbine Establishment,Chengdu 610500,China

出　　处：《Journal of Advanced Ceramics》2021年第3期551-564,共14页先进陶瓷（英文）

基　　金：This study is supported by the National Natural Science Foundation of China(Nos.1171101165 and 11902240).

摘　　要：Calcium-magnesium-alumino-silicate(CMAS)corrosion is a critical factor which causes the failure of thermal barrier coating(TBC).CMAS attack significantly alters the temperature and stress fields in TBC,resulting in their delamination or spallation.In this work,the evolution process of TBC prepared by suspension plasma spraying(SPS)under CMAS attack is investigated.The CMAS corrosion leads to the formation of the reaction layer and subsequent bending of TBC.Based on the observations,a corrosion model is proposed to describe the generation and evolution of the reaction layer and bending of TBC.Then,numerical simulations are performed to investigate the corrosion process of free-standing TBC and the complete TBC system under CMAS attack.The corrosion model constructs a bridge for connecting two numerical models.The results show that the CMAS corrosion has a significant influence on the stress field,such as the peak stress,whereas it has little influence on the steady-state temperature field.The peak of stress increases with holding time,which increases the risk of the rupture of TBC.The Mises stress increases nonlinearly along the thick direction of the reaction layer.Furthermore,in the traditional failure zone,such as the interface of the top coat and bond coat,the stress obviously changes during CMAS corrosion.

关 键 词：thermal barrier coating(TBC) calcium-magnesium-alumino-silicate(CMAS)corrosion corrosion model temperature field stress field 

分 类 号：TG174.4[金属学及工艺—金属表面处理]