Bolun Li , Hairong Gu , Yipin Wan , Anye Xu , Xuding Song
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引用次数: 0
Abstract
7075 aluminum alloy has high strength but poor weldability, even though applying laser welding, welded 7075 aluminum alloy still shows poor fatigue properties. In this study, laser shock peening (LSP) is used in the welded zone and the heat affected zone to improve the fatigue properties of the welded joints. The surface roughness, hardness, fatigue crack propagation and tensile with digital image correlation tests are carried out, and the microstructure is observed by scanning electron microscope and electron back scatter diffraction. Results show that the hardness values, proportion of high angle grain boundaries and grain dislocation density are increased, so that the higher energy LSP can significantly improve ultimate tensile stress and fatigue crack propagation behavior of welded joints. Meanwhile, the higher energy LSP significantly decreases surface roughness in the welded zone of welded joints.
期刊介绍:
Theoretical and Applied Fracture Mechanics'' aims & scopes have been re-designed to cover both the theoretical, applied, and numerical aspects associated with those cracking related phenomena taking place, at a micro-, meso-, and macroscopic level, in materials/components/structures of any kind.
The journal aims to cover the cracking/mechanical behaviour of materials/components/structures in those situations involving both time-independent and time-dependent system of external forces/moments (such as, for instance, quasi-static, impulsive, impact, blasting, creep, contact, and fatigue loading). Since, under the above circumstances, the mechanical behaviour of cracked materials/components/structures is also affected by the environmental conditions, the journal would consider also those theoretical/experimental research works investigating the effect of external variables such as, for instance, the effect of corrosive environments as well as of high/low-temperature.