摘要
研究了AZ91D+0.3%La镁合金在总应变幅Δεt/2为0.2%～1.2%范围内循环加载时的低周疲劳行为。结果表明,在较大应变幅下,AZ91D+0.3%La镁合金的循环滞后回线上分别出现拐点、拉压不对称和锯齿现象;镁合金的低周疲劳寿命随应变幅值的提高而下降,并且符合Manson-Coffin关系式;镁合金的循环应力响应行为和循环应力应变行为均呈现明显的循环硬化现象;疲劳断口上出现了多疲劳源现象,且随应变幅的增加越来越凹凸不平。
Lwo eyele fatigue properties of AZ91D＋0.3%La alloy were studied by fatigue testing meehine with equivalent strain amplitude varied from 0.2%-1.2%. The results indicated that the σ-ε hysteresis loops of AZ91D＋0.3La magnesium alloy with some behaviors such as inflexion, asymmetry of tension and compression and saw teeth phenomenon were showed at the higher total strain amplitudes. The fatigue life of AZ91d＋0.3%l,a alloy is decreased with the increase of the equivalent strain amplitude,according with the Manson-Coffin equation.Behaviors of the cyclic stress response and the cyclic stress-strain of the alloy show cyclic strain hardening phenomenon obviously. Several fatigue resoures are occurred in fatigue frature surface,and become more rough and coneavo-eonvex with the increase of the strain amplitude.
出处
《铝加工》
CAS
2009年第5期4-9,共6页
Aluminium Fabrication
