Vibration fatigue life and fracture analysis of 2024-T351 aluminum alloy treated by cryogenic laser peening.

A Nd:YAG nanosecond pulsed laser was used to carry out laser peening and cryogenic laser peening (CLP) experiments at room temperature (25°C) and cryogenic temperature (-100∘C), respectively, on the vibration fatigue life of 2024-T351 aluminum alloy. It was found that CLP induced a higher amplitude of compressive residual stress and improved the nano-hardness and the elastic modulus. Compared to the LP-ed samples, the fatigue life of the CLP-ed specimens was higher, and the initiation and propagation of fatigue cracks were more effectively inhibited. Therefore, CLP can effectively improve the fatigue performance of aluminum alloys.