滚筒强化对2D70铝合金厚板表面应力以及组织和性能的影响

2D70铝合金是应用广泛的中强度铝合金,为了消除材料经机加工后在表面形成的残余拉应力,本工作研究了滚筒强化工艺对2D70铝合金厚板表面残余应力、表面形貌、高低频光滑疲劳性能及疲劳裂纹源的影响.结果表明,滚筒强化处理在2D70试样表面造成了残余压应力,但是同时也对试样表面造成某种程度的损伤,对最终材料高、低频光滑试样的疲劳性能影响不大,滚筒强化处理改变了疲劳裂纹的起源.

The Effect of Surface Strengthening by Revolving Canister on the Microstructure and Mechanical Properties of 2D70 Aluminum Alloy

In order to eliminate the stretch residual stress in surface of the 2D70 aluminum alloy, which has a medium strength and been widely used, the effect of surface strengthening by revolving canister on the microstructure and mechanical properties was studied.The emphases were on the surface residual stress, surface morphology, fatigue under high or low frequency and the origins of the fatigue cracks.The results showed that although the compress residual stress was obtained, some damages were also found in the surface after the samples were treated by revolving canister strengthening.The fatigue strength and life under high or low frequency were little influenced, but the origins of fatigue cracks were obviously altered by the processing of revolving canister strengthening.