In situ X-ray observation of semi-solid deformation and failure in Al-Cu alloys
In situ X-ray observation of semi-solid deformation and failure in Al-Cu alloys
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DOI：
10.1016/j.actamat.2010.11.005
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发表时间：
2011-02-01
期刊：
影响因子：
9.4
通讯作者：
Lee, P. D.
中科院分区：
文献类型：
--
作者：
Phillion, A. B.;Hamilton, R. W.;Lee, P. D.
通过结合实时同步加速器 X 射线照相术和定制的高温拉伸测试仪，在 0.35 至 0.98 的固相分数范围内直接观察到 Al-12 wt.% Cu 合金的半固态变形。在低和中等固体分数变形过程中，X 射线射线照片表明，在裂纹形成之前，在应变局部化区域存在显着的枝晶间液体供给。此外，发现引发局部拉伸变形所需的测量载荷在固体分数 0.35 至 0.66 的范围内相似。在固体含量较高的情况下，射线照相观察结果与经典的热撕裂行为一致：由于渗透性低，液体流动有限；空洞成核和聚结；以及最终的失败。基于这些结果，提出了半固态失效的三阶段机制，其中包括液体流动和微颈形成的影响。 (C) 2010 Acta Materialia Inc. 由 Elsevier Ltd 出版。保留所有权利。
Semi-solid deformation has been directly observed in an Al-12 wt.% Cu alloy through the combination of real-time synchrotron Xray radiography and a bespoke high-temperature tensile tester over a range of fraction solid from 0.35 to 0.98. During deformation at low and moderate fraction solids, the X-ray radiographs indicate that there is significant feeding of interdendritic liquid in the region of strain localization prior to crack formation. Furthermore, the measured load required to initiate localized tensile deformation was found to be similar over the range of fraction solid 0.35 to 0.66. At higher fraction solids, the radiographic observations are consistent with classical hot tearing behaviour: limited liquid flow due to low permeability; void nucleation and coalescence; and final failure. Based on these results, a three-stage mechanism for semi-solid failure is proposed which includes the effects of liquid flow and micro-neck formation. (C) 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.