变几何涡轮调节机构高温自润滑摩擦副设计及验证

This study addresses the demands of high-temperature variable geometry turbine（VGT）adjustment mechanism in variable cycle engines. A novel self-lubricating material with a multilayer material system comprising NiCrAlY/ZrO₂ （Y₂O₃）+lubricating phase+hard phase was employed in VGT adjustment mechanism. A two-dimensional kinematic analysis model is established based on the typical sliding and rotating friction pairs，which enables rapidly acquisition of load characteristics. On this basis，a critical surface strength evaluation method was developed，based on tensile and crushing tests，which can more accurately characterize the stress state of self-lubricating materials and predict the failure mode of bushings，thereby further guiding the design of high-temperature self-lubricating friction pairs and improving the adjustment accuracy of VGT. The design and experimental validation of the VGT adjusting mechanism test component have been completed. The test results indicate that：The active blades exhibit consistency in both lift stroke and return stroke，with an adjustment accura⁃ cy ≤0.2°；With the temperature range of 100~400 ℃，the angular deviation of lift-return stroke between active and passive blades do not exceed 0.49°；The lift-return accuracy of active blades is superior to that of passive blades. Post-test inspections revealed excellent condition of all friction pairs，further validating the reliability of the friction components in the adjustment mechanism.