| Due to the lower weight density and higher strength of Ceramic Matrix Composites(CMCs)than that of high-temperature alloy,CMCs has been wildly used in producing the hot-section components of the aero engine.Coefficient of Thermal Expansion(CTE)is the basic parameter to describe the thermal deformation of materials.Experimental and theoretical researches about the CTE of CMCs have been reported.The thermal deformation of CMCs relates to the damage,and damage caused by external load affects the thermal deformation of CMCs.There is no public report on the related research.In this paper,the Digital Image Correlation technology is used to measure the thermal deformation of CMCs under different tensile loads,and the influence of temperature is also studied.The paper also carried out the CMCs cyclic loading test,and studied the effect of cyclic loading on the thermal deformation of CMCs.On this basis,the effect of temperature is introduced into the interface friction model,and the thermal deformation calculation model of mini-composite is established.Finally,based on the thermal deformation test results of mini-composites,combined with the finite element method and homogenization method,the thermal deformation calculation of plain woven CMCs under constant load is realized.The main conclusions obtained in this paper are as follows: When the mini-composite is subjected to a constant load,the thermal deformation increases with the load at different temperatures.The cyclic loading has an effect on the thermal deformation of the plain woven SiC/SiC composites,and the thermal deformation becomes larger with the increase of the cycle number.The interface friction model was introduced with the effect of temperature.The calculated results were in good agreement with the thermal deformation test results of mini-composite materials.The calculation results of the microscopic model of the plain woven SiC/SiC composites are also in agreement with the experimental results. |
