Fatigue crack growth behavior and fatigue damage resistance mechanism of Al-Li alloy
The fatigue crack growth(FCG)features and fatigue damage resistance mechanism of Al-Li alloys were summarized.Based on the description of precipitation strengthening mechanism(shearing mechanism and by-passing mechanism),the FCG rate dependences of Al-Li alloys on precipitate evolution were expounded in detail.The effects of grain structures(recrystallization degree,grain boundary density,grain size and grain orientation)on their FCG rates were then emphatically discussed.The exploitation approach,composition and microstructure design ideas,FCG properties of the 3rd generation fatigue damage resistant Al-Li alloys were summarized.On the comments of the development gap of domestic and international fatigue damage resistant Al-Li alloys,the future research on damage resistant Al-Li alloys in China was proposed.