On the effects of the Mg content on the critical strain for the jerky flow of Al-Mg alloys
On the effects of the Mg content on the critical strain for the jerky flow of Al-Mg alloys
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DOI：
10.1016/j.msea.2015.02.055
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发表时间：
2015-04
期刊：
影响因子：
6.4
通讯作者：
H. Ait-Amokhtar;C. Fressengeas;K. Bouabdallah
中科院分区：
文献类型：
--
作者：
H. Ait-Amokhtar;C. Fressengeas;K. Bouabdallah
在施加应变速率和室温下进行拉伸试验期间，研究了铝镁合金的急流。结合镁含量研究了应力降大小、塑性不稳定性范围和锯齿开始临界应变的应变和应变速率依赖性。在应变率不稳定范围的低应变率部分，临界应变随着Mg含量的增加而降低。当镁含量增加时，对应于临界应变与施加应变率曲线的最小值的临界应变率转变为更大的值。这种行为导致临界应变逆行为的应变率域扩大，但牺牲了正常行为的域。在不稳定范围的高应变率部分，临界应变不依赖于Mg含量。这些结果根据动态应变时效机制进行了讨论。
The jerky flow of Al–Mg alloys is investigated during tensile tests at imposed strain rate and room temperature. The strain and strain rate dependences of the magnitude of the stress drops, the range of plastic instability and the critical strain for the onset of serrations are studied in connection with the Mg content. In the low strain rate part of the strain rate range of instability, the critical strain decreases with the Mg content. The critical strain rate corresponding to the minimum of the critical strain vs. applied strain rate curve shifts to larger values when the Mg content increases. This behavior leads to an enlargement of the strain rate domain of inverse behavior of the critical strain, at the expense of the domain of normal behavior. In the high strain rate part of the range of instability, the critical strain does not depend on the Mg content. These results are discussed in accordance with dynamic strain aging mechanisms.