涡轮叶片榫齿部位疲劳/蠕变试验的新特点

在某型航空发动机涡轮叶片的低周疲劳试验中发现, 叶片疲劳/蠕变试验寿命高于纯疲劳试验寿命, 为探究这一现象的原因, 对此展开相关的理论计算和分析.研究表明:试验条件较好地模拟了叶片的实际工作条件, 该涡轮叶片的损伤以疲劳损伤为主, 相对于真实涡轮叶片的纯疲劳试验, 在疲劳/蠕变试验条件下, 其考核部位(榫齿)出现了较大的应力松弛, 故而使得叶片疲劳/蠕变寿命高于纯疲劳寿命.研究结果对于保证发动机安全工作、提高飞行可靠性、以及发展高温构件的疲劳试验技术有重要意义. 

New characteristics of fatigue-creep tests on serration of turbine blades

The fatigue-creep life was found to be longer than the fatigue life from the Low Cycle Fatigue experiment of turbine blade of an aeroengine.The relevant theoretical calculation and analysis were then carried out to provide a further insight into such phenomenon.The research shows that: the actual working conditions of blades were well simulated in the experimental conditions,indicating that the damage of blade was mainly attributable to fatigue damage.As compared with pure fatigue test of real turbine blade,stress relaxation occurred at the key section(serration) under fatigue-creep test conditions,showing that fatigue/creep life of blade was longer than fatigue life.The research results play a key role in ensuring the safety of engines,improving the flight reliability and developing fatigue test techniques of high-temperature components.