为了研究激光辅助成形样件的疲劳性能及喷丸处理的作用规律,以2024铝合金板材为对象,对原始、激光辅助成形以及激光辅助成形后再喷丸等样件的微观组织、显微硬度、残余应力和拉-拉疲劳性能进行了对比分析研究。结果表明:激光辅助成形后,样件的组织和微结构未发现明显变化,但其硬度和残余拉应力水平有所下降;喷丸处理的激光辅助成形样件表层组织改变、显微硬度提高、其拉-拉疲劳寿命显著提高,不仅高于激光辅助成形样件,也高于初始样件。
In order to study the fatigue properties of laser aided forming samples and realize the effects of shot peening treatment on these samples, with aluminum alloy plate 2024 as the test object, the microstructure, microhardness, residual stress and tension-tension fatigue properties of as-machined aluminum samples, samples of laser aided forming and shot peened samples are studied. The results show that the microstructures of laser aided forming samples are not varied obviously, but their microhardness and extensive residual stress decrease, while after shot peening the surface microstructures of the laser aided forming samples become varied, their microhardness is raised and their fatigue properties are greatly improved. The tension-tension fatigue lives of shot peened samples are not only higher than the laser aided forming samples, but also higher than the as-machined aluminum samples.
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