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The damage evolution and failure process of pre-corroded additive manufacturing AlSi10Mg through in-situ tensile experiments under an optical microscope and micro-scale digital image correlation（μ-DIC） were investigates . Combining the microscopic deformation field evolution，material microstructure，three-dimensional corrosion morphology and fracture microscopic morphology to analyze the initiation and propagation of micro-cracks in pre-corroded AlSi10Mg. The results show that the stress concentration around the corrosion pits and subsurface defects（caused by the additive manufacturing process） leads to the initiation of micro-cracks. There are multiple micro-cracks initiating at the same time，and the propagation and coalescence of micro-cracks originated from the key damage regions dominate the final failure of the specimen. Material micro-structure and corrosion morphology have an important influence on crack propagation.

The fatigue cracking behavior in pre-corroded AA2024-T4 associated with three different levels of maximum stresses and stress ratios via three-dimensional digital image correlation (3D-DIC) was investigated. The spatial-temporal characteristic of crack initiation and propagation was visually displayed through strain field evolution, while the fracture morphology of determined key damage regions was further examined. Experimental results show that localized corrosion penetrated in the edges of specimens promotes fatigue crack initiation and affects crack nucleation location, accompanied with hydrogen embrittlement. Identified crack orientations (range 60°-68° from the loading direction) reveal that the early growth of fatigue crack can be described by KⅠ/KⅡ-mixed mode. Four typical failure modes (single crack fracture, multi-crack coalescence, multi-crack competition and multi-crack parallel growth) are observed and discussed.