| 摘要: |
| 梯度阻热涂层(由不同混合比的阻热涂层和底层材料组成)可以降低阻热涂层(陶瓷)材料和底层(金属)材料之间因热失配而产生的热应力.结合纯声子散射模型(用于梯度阻热涂层)与傅里叶热传导模型(用于底层)，用数值方法求解梯度阻热涂层的温度场和应力场，研究了阻热涂层参数(松弛时间、声子速度)梯度分布对温度场的影响以及阻热涂层力学性能(弹性模量、热膨胀系数)梯度分布对热应力的影响.结果表明：阻热涂层参数梯度分布能明显减小梯度阻热涂层的温度梯度；阻热涂层力学性能梯度分布能降低梯度阻热涂层的热应力，其中热膨胀系数梯度分布的影响明显大于弹性模量梯度分布的影响. |
| 关键词: 阻热涂层 纯声子散射模型 温度梯度 热应力 热力学参数 |
| DOI：103969/jissn1007 9629201501011 |
| 分类号: |
| 基金项目: |
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| Thermodynamic Analyses of Gradient Thermal Barrier Coatings by Phonon Scattering Model |
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ZHANG Shiyuan1, ZHENG Bailin2, HE Pengfei2
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1.Department of Civil Engineering, Fujian University of Technology, Fuzhou 350108, China;2.School of Aerospace Engineering and Applied Mechanics, Tongji University, Shanghai 200092, China
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| Abstract: |
| Gradient thermal barrier coatings（gradient TBCs） composed of different mix ratio of thermal barrier coatings and substrate are used as intermediate layer in order to reduce thermal stress resulted from heat mismatch between two materials. Temperature gradient and thermal stress of gradient TBCs were numerically calculated by combining phonon scattering model（for gradient TBCs） and Fouier heat conduction model（for substrate). The effects of the thermal physical properties（relaxation time and phonon speed） on the temperature field, the influences of gradient distribution of the elastic modulus and coefficient of thermal expansion on thermal stress are discussed. It is concluded that in the gradient TBCs, maximal values of thermal stress, temperature gradient are lower than that in constant TBCs. The effect of the thermal expansion coefficient on thermal stress is greater than the effect of the elastic modulus on thermal stress. |
| Key words: thermal barrier coatings(TBCs) phonon scattering model temperature gradient thermal stress thermodynamic parameter |
