The workability evaluation of wrought AZ80 magnesium alloy in hot compression
The workability evaluation of wrought AZ80 magnesium alloy in hot compression
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DOI：
10.1016/j.matdes.2010.11.025
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发表时间：
2011-04
影响因子：
8.4
通讯作者：
Guo-zheng Quan;T. Ku;Woojin Song;B. Kang
中科院分区：
文献类型：
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作者：
Guo-zheng Quan;T. Ku;Woojin Song;B. Kang
加工性是金属成形过程中的一个重要参数，可以通过基于动态材料模型（DMM）的加工图来评价。动态材料模型是由实验产生的流变应力随应变、应变速率和温度的变化而建立的。为了获得变形AZ 80镁合金的加工图，在温度523- 673 K和应变速率0.01- 10 s-1的范围内进行热压缩试验。当真应变分别为0.25、0.45、0.65、0.85时，计算了应变率敏感性（m值）、功率耗散效率（η值）和失稳参数（η值）对温度和应变率的响应。通过功率耗散图和不稳定性图的叠加，清晰地划分了稳定区、亚稳定区和不稳定区。在此基础上，在稳定区域中，确定并推荐了功率耗散效率最高的区域。由工艺图确定的最佳工艺参数有助于设计无缺陷AZ 80镁合金的热成形工艺。
Workability, an important parameter in metal forming process, can be evaluated by means of processing maps on the basis of dynamic materials model (DMM), constructed from experimentally generated flow stress variation with respect to strain, strain rate and temperature. To obtain the processing maps of wrought AZ80 magnesium alloy, hot compression tests were performed over a range of temperatures 523–673K and strain rates 0.01–10s−1. As the true strain is 0.25, 0.45, 0.65, 0.85 respectively, the response of strain-rate sensitivity (m-value), power dissipation efficiency (η-value) and instability parameter (ξ-value) to temperature and strain rate were evaluated. By the superimposition of the power dissipation and the instability maps, the stable, metastable and unstable regions were clarified clearly. In further, in the stable area the regions having the highest efficiency of power dissipation were identified and recommended. The optimal working parameters identified by the processing maps contribute to designing the hot forming process of AZ80 magnesium alloy without any defect.