The delamination growth in FMLs under fatigue load based on DIC method

Glass fiber reinforced aluminum alloy laminates (FMLs) is a new kind of composite material, which has more excellent specific strength, specific stiffness, anti-fatigue and impact resistance. Delamination is the main damage of FMLs. This paper designed several samples with different notch sizes and performed the delamination growth under different fatigue loads. Based on DIC method, the shapes and sizes of delamination and crack lengths were calculated. It is shown that delamination growth slows down along the loading direction with crack growing. The crack growth rates decrease firstly, then remain almost stable for a long crack growth, and rise rapidly at last. The effects of stress ratios and notch sizes on delamination growth and crack propagation were analyzed.