摘要
利用有限元方法,采用弹塑性理论对FeCrAl合金基陶瓷涂层中的应力场进行了数值模拟,得出了陶瓷涂层中应力σx(在x方向)、σy(在y方向)和τxy(x-y平面)的分布特征。研究表明在试样近边缘处涂层界面的残余拉应力σx和σy出现极大值,对于上部涂层分别为40和43.04MPa,对于侧面涂层分别为40.40和43.38MPa。涂层开裂或剥落最有可能从此处开启,然后在残余压应力σx(上部涂层)、σy(侧面涂层)和剪切应力τxy的作用下向试样中部涂层中扩展,从而导致涂层的保护功能失效。模拟结果与试样的抗热冲击试验获得较好吻合。
The distribution of residual thermal stresses of the ceramic coating on FeCrAl-alloy was simulated using FEM with elastic-plastic analysis method. And the distribution of residual stresses σx （at x direction）,σy （at y direction） and τxy （x-y plane） were also discussed. The result shows that the flaws would appear in the interfaces of the ceramic coating at the edge of the specimen due to maximum residual tensile stress σx and σy, which may arrive at 40 and 43.04 MPa for the upside coating, 40.40 and 43.34 MPa for the side coating respectively, and flaws extend into middle part of the ceramic coating due to residual compressive stress σx （upside coating） or σy （side coating） and shear stress τxy. Therefore, protection functions of the ceramic coating to FeCrAl-alloy would fail. Results of simulation are consistent with experiments of thermal shock resistance of the specimen.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2010年第A01期177-181,共5页
Rare Metal Materials and Engineering
基金
江西省教育厅重点支持项目(赣教计字2001-387)
