陶瓷层孔隙对热障涂层TGO界面残余应力影响的有限元研究

作为一种热障涂层不可避免的结构缺陷,孔隙的存在具有随机性,其分布位置会给TGO(热生长氧化层)界面残余应力带来巨大影响。为了更好地了解孔隙率对热障涂层TGO界面残余应力的影响,考虑单个孔隙对TGO界面残余应力的影响,通过改变孔隙与TGO界面的距离、孔隙位置及孔隙的尺寸,来分析TGO界面残余应力的变化情况。结果表明:当半径为5μm的圆形孔隙与TGO/TC界面距离为35μm时,孔隙几乎对TGO界面残余应力没有影响,孔隙离界面越近,对残余应力的大小及分布影响越大;距离一定时,孔隙尺寸越小对界面残余应力的影响越小。

Finite Element Study of the Influence of Ceramic Layer Porosity on Interfacial Residual Stress of Thermal Barrier Coatings TGO

As an inevitable structural defect of thermal barrier coatings,the existence of pores is random and its distribution position has great influence on the residual stress of thermal growth oxidation(TGO)interface.In order to better understand the effect of porosity on the interfacial stress of TGO in thermal barrier coating,the effect of single pore on the residual stress of the TGO interface was considered,the variation of residual stress at TGO interface was analyzed by changing the distance between pores and TGO interface,the pore location and pore size.The results showed that when the radius of the circular pore was 5 um and the distance from the TGO/TBC interface was 35 um,the porosity was shown almost no influence on the residual stress in the TGO interface,and the closer the pore to the interface,the greater the influence of the residual stress on the size and distribution.When the distance was fixed,the smaller the pore size was,the smaller the interfacial residual stress would be.