On the roles of stress-triaxiality and strain-rate on the deformation behavior of AZ31 magnesium alloys
On the roles of stress-triaxiality and strain-rate on the deformation behavior of AZ31 magnesium alloys
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DOI：
10.1080/21663831.2017.1417923
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发表时间：
2018-02
影响因子：
8.3
通讯作者：
C. Kale;M. Rajagopalan;S. Turnage;B. Hornbuckle;K. Darling;S. Mathaudhu;K. Solanki
中科院分区：
文献类型：
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作者：
C. Kale;M. Rajagopalan;S. Turnage;B. Hornbuckle;K. Darling;S. Mathaudhu;K. Solanki
复杂应力状态和应变率的存在直接影响给定材料在载荷作用下的主要变形机制。由于缺乏主动滑移机制，镁合金表现出有限的室温成形性，然而，研究主要集中在准静态应变率和/或简单加载条件（主要是单轴或双轴）。本文首次利用应变速率和应力三轴性的影响，揭示了az31合金变形后沿轧制、横向和法向的主动变形机制。研究发现，在多轴载荷作用下，各种双机制的激活是由外加应变率的能量学决定的。研究首次表明，在高c/a比的HCP合金中，动态应变率下的高变形能和高三轴性促进了脱孪和织构的演化。图形抽象
ABSTRACT The presence of complex states-of-stress and strain-rates directly influence the dominant deformation mechanisms operating in a given material under load. Mg alloys have shown limited ambient temperature formability due to the paucity of active slip-mechanisms, however, studies have focused on quasi-static strain-rates and/or simple loading conditions (primarily uniaxial or biaxial). For the first time, the influence of strain-rate and stress-triaxiality is utilized to unravel the active deformation mechanisms operating along the rolling, transverse- and normal-directions in wrought AZ31-alloy. It is discovered that the activation of various twin-mechanisms in the presence of multiaxial loading is governed by the energetics of the applied strain-rates. IMPACT STATEMENT It is shown for the first time that the higher deformation energy associated with dynamic strain-rates, coupled with high-triaxiality, promotes detwinning and texture evolution in HCP alloys with high c/a ratio. GRAPHICAL ABSTRACT