Improved mechanical property and internal friction of pure Mg processed by ECAP
Improved mechanical property and internal friction of pure Mg processed by ECAP
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DOI：
10.1016/j.msea.2012.07.031
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发表时间：
2012-10-30
期刊：
影响因子：
6.4
通讯作者：
Golovin, I. S.
中科院分区：
文献类型：
--
作者：
Fan, G. D.;Zheng, M. Y.;Golovin, I. S.
对挤压后的纯镁进行等道角挤压。在不牺牲强度的情况下，eced纯Mg的失效延伸率提高到27%，这主要是由于晶粒尺寸的有效细化和基面织构的弱化。采用动态力学分析仪（DMA）研究了镁在室温和高温下的内摩擦机理。经ECAP处理后，应变无关内摩擦增大，应变相关内摩擦明显减小。在温度相关的内摩擦曲线上观察到三个内摩擦峰。P-1峰的活化能为105 kJ/mol，这可能与位错基底滑移受位错爬升和空位沿位错扩散控制有关。P-2峰的活化能在95 ~ 181 kJ/mol之间，这一明显展宽的峰与晶界松弛有关。P-3峰与再结晶有关。(c) 2012 Elsevier B.V.版权所有
Equal channel angular pressing was performed on the extruded pure Mg. The elongation to failure of the ECAPed pure Mg is enhanced to 27% without sacrificing the strength, which is mainly resulted from both the effective refinement of grain size and the weakening of the basal plane texture. The internal friction mechanisms of magnesium at room and elevated temperature were studied by dynamic mechanical analyzer (DMA). The strain independent internal friction is increased after ECAP processing, while the strain dependent part is obviously decreased. Three internal friction peaks were observed in the temperature dependent internal friction curves. The activation energy is 105 kJ/mol for P-1 peak, which may be related to the basal dislocation glide controlled by climb of jogs and diffusion of vacancies along dislocations. The activation energy of P-2 peak is in the range from 95 to 181 kJ/mol, and this obviously broadened peak is associated with grain boundary relaxation. The P-3 peak is related to recrystallization. (c) 2012 Elsevier B.V. All rights reserved.