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通过有限元分析软件Abaqus,采用三维模型,对热障涂层表面强流脉冲电子束改性过程进行了数值模拟,分析了电子束轰击过程温度变化以及涂层系统内部应力的分布情况。计算结果表明,随着外界能量的增加,涂层温度随着涂层厚度的增加而降低;当外界能量消失时,冷却过程中,由于涂层表面和周围的热辐射和热扩散作用,陶瓷层表面最先冷却,此时陶瓷层内部温度略微升高,之后陶瓷层内部热能通过陶瓷层表面进行释放,最后整个涂层冷却到室温,温度随时间变化率高达106~107 K/s。冷却至室温时,应力随着陶瓷层厚度的增加呈现先减小后增大的趋势,而在涂层表面径向应力先减小后增大,达到0.5MPa后,应力开始减小至稳态值。
Through the finite element analysis software Abaqus, the three-dimensional model was used to simulate the high-current pulsed electron beam modification on the surface of the thermal barrier coating. The temperature variation during the electron beam bombardment and the distribution of internal stress in the coating system were analyzed. The results show that with the increase of external energy, the temperature of the coating decreases with the increase of the coating thickness. During the cooling process, due to the thermal radiation and thermal diffusion on the surface and surrounding of the coating, The surface is cooled first, and the internal temperature of the ceramic layer rises slightly. After that, the internal thermal energy of the ceramic layer is released through the surface of the ceramic layer. Finally, the entire coating is cooled down to room temperature, and the rate of change over time is as high as 106 to 107 K / s. When cooled to room temperature, the stress decreases first and then increases with the increase of the thickness of ceramic layer, but decreases first and then increases at the surface of the coating. After reaching 0.5 MPa, the stress begins to decrease to the steady state value.