涡轮叶片叶冠篦齿径向裂纹的快速扩展会危及发动机的安全运行，为明确摩擦温度对裂纹形成的影响，使用自建的高速摩擦试验台开展试验研究，解析分析径向裂纹的形成机理及摩擦温度和对流换热系数对裂纹形成的影响，并基于Abaqus的XFEM模型进行数值分析及验证。试验表明摩擦温度温升在200℃以上才能形成径向裂纹，得到了形成径向裂纹的温度下降曲线拟合式。解析分析表明径向裂纹的形成与摩擦温度、环境温度、对流换热系数和篦齿的导热有关。数值计算得到了径向裂纹的形成过程，温度低于1068℃时没有萌生裂纹，温度超过1124℃在压应力的作用下在顶面中间形成了沿周向扩展的裂纹，在1068℃~1124℃的温度范围在拉应力的作用下形成径向裂纹。摩擦温度和对流换热系数的增大会促进径向裂纹的形成，摩擦温度的影响更明显。
The rapid propagation of radial cracks in the crown fin of turbine blades can endanger the safe operation of the engine. In order to clarify the influence of friction temperature on crack formation, a custom-designed high-speed friction test rig was used to conduct experimental research. The formation mechanism of radial cracks and the influence of friction temperature and convective heat transfer coefficient on crack formation were analyzed, and numerical analysis were carried out based on Abaqus' XFEM model. Experiments have shown that radial cracks exclusively manifest when the friction temperature surpasses 200 ℃, and a fitting formula for the temperature drop curve that forms radial cracks has been obtained. Numerical simulations illuminated the process of radial crack development. Specifically, no cracks were initiated below 1068 ℃, whereas above 1124 ℃, cracks propagated circumferentially across the top surface's midsection under compressive stress. Within the temperature range of 1068 ℃ to 1124 ℃, radial cracks emerged under tensile stress conditions. Both elevated friction temperatures and convective heat transfer coefficients expedite radial crack formation, with friction temperature exerting a more pronounced influence.
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