| 摘要: |
| 针对复合涂层的现有仿真方法多基于单一物理场的影响，不能反映多物理场耦合作用等实际工况下的力学性能。以航空发动机附件机匣的典型工况环境为背景，建立描述流-固-热耦合作用下梯度复合涂层各物理参数变化的数学模型，计算涂层不同分布方式下其内部的 von Mises 应力分布。结果表明，过渡层材料组分的渐变方式对涂层热应变和层内 von Mises 应力分布有较大影响，以航空发动机附件机匣中某型花键副为例，在施加实际工况下的载荷和温度条件后，温度场引起的热应力较载荷-润滑引起的应力更大，在润滑、热场和载荷的耦合作用下，三种分布方式的涂层最大应力均位于表层，随梯度的增大逐渐向基体扩散；梯度增大的过渡方式在涂层内可以获得最小的最大 von Mises 应力。在所关注的温度范围内，与梯度减小的过渡方式相比，使用梯度增大的过渡方式可使最大 von Mises 应力减小 14.5%。所建立的仿真方法可模拟近似实际工况， 研究结果可用于指导梯度复合涂层的设计和制备。 |
| 关键词: 复合涂层 梯度复合涂层 流-固-热耦合 力学性能 |
| DOI：10.11933/j.issn.1007-9289.20211104003 |
| 分类号:TB12 |
| 基金项目:国家科技重大专项(2019-VII-0015-0155)；国家自然科学基金(52005033)资助项目 |
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| Simulation Analysis of Stress Distribution of Gradient Composite Coatings under the Application of Fluid-solid-thermal Coupling |
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FANG Boshi1, YANG Wenming1, CHEN Haosheng2
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1.School of Mechanical Engineering, University of Science and Technology Beijing,Beijing 100083 , China;2.Department of Mechanical Engineering, Tsinghua University, Beijing 100084 , China
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| Abstract: |
| Previous simulation methods for composite coatings are mostly based on the influence of one single physical field, which cannot reflect the real mechanical properties under actual working conditions such as multi-physics coupling. According to the typical working conditions of aero-engine accessories, a mathematical model describing the fluid-solid-thermal coupling phenomenon for gradient composite coatings is established, and the distribution of von Mises stress inside the coatings for different changing ways of compositions is calculated. It is shown that the three transition ways cast different results of thermal strain and von Mises stress in the coatings. Take the spline used in the aero-engine accessories as an example, the thermal stress is much larger than the stress caused by load-lubrication coupling under the application of the actual load and temperature conditions. With the action of the coupling effects of load-thermo-lubrication, the maximum stress locates at the surface layer and the stress spreads to the substrate with the increase of composition gradient. The transition way with increasing gradient can obtain the smallest “max von Mises stress” in the coatings. Within the temperature range of interest, the “max von Mises stress” reduces 14.5% by comparison with that for the decreasing gradient method. The simulation methods established can simulate the actual working conditions more closely. The research results can be used to guide the design and preparation of gradient composite coating. |
| Key words: composite coatings gradient composite coatings fluid-solid-thermo coupling mechanical property |
