DZ—22定向凝固高温合金复合疲劳特性的研究

本文模拟航空发动机叶片在服役状态下的疲劳行为，研究了ＤＺ－２２定向凝固合金在不同试验温度、不同低循环应力下，高低循环复合疲劳特性。结果表明，在低循环载荷上叠加高特振动载要使复合疲劳寿命下降，但若高频振幅小于某一临界值时，其复合疲劳寿命反而会明显增长，这是由于高频小幅值振动起到次负荷锻炼作用使材料得到强化，且在高低循坏复合疲劳过程中抑制了疲劳损伤。

Study on Complex Fatigue Properties of Direct ionalloy Solidified High Temperature DZ-22 Alloy

Fatigue behaviours of aeronautic engine blade on operating duty were imitated to research high-low cycle complex fatigue properties of directionally solidified high temperature DZ-22 alloy on the conditions of different test temperature,differenft low cycle stress. Results show thst complex fatigue life was shortened when a high cycle vibration load was added to low cycle load , but was distinctly longered when high frequent vibration amplitude was lowed to a boundary value. This due to the small vibration amplitude which take the function of secoondary load exercise and strengthen the material. Creep damage is restrained in the process it high - low cycle complex fatigue.