Enhanced fracture toughness and strength in bulk nanocrystalline Cu with nanoscale twin bundles
Enhanced fracture toughness and strength in bulk nanocrystalline Cu with nanoscale twin bundles
复制标题
具有纳米级孪晶束的块状纳米晶铜具有增强的断裂韧性和强度
DOI：
10.1016/j.actamat.2009.08.048
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发表时间：
2009-12-01
期刊：
影响因子：
9.4
通讯作者：
Lu, K.
中科院分区：
文献类型：
--
作者：
Qin, E. W.;Lu, L.;Lu, K.
采用低温动态塑性变形（DPD）法制备了包埋纳米孪晶束的块状纳米纯铜样品。通过调整DPD参数，我们增加了纳米孪晶束的体积分数，从而提高了拉伸强度和断裂韧性。强度的提高主要是由于纳米孪晶束的强化作用。高度各向异性的纳米孪晶片层结构在断裂过程中具有有效的能量吸收和阻止裂纹扩展的作用。由于纳米孪晶束的存在，在断口表面发现了与明显的再结晶相关的粗的和深的韧窝。断裂韧性的增强与这些深韧窝的形成密切相关。(C) 2009材料学报Elsevier Ltd.出版。版权所有。
Bulk nanocrystalline pure Cu samples with embedded nanoscale twin bundles were prepared by means of dynamic plastic deformation (DPD) at cryogenic temperature. By adjusting the DPD parameters, we increased the volume fraction of nanotwin bundles, resulting in an increase in both tensile strength and fracture toughness. The enhanced strength is attributed to the strengthening effect of the nanotwin bundles. The highly anisotropic nanotwin lamellar structures are found to be effective in energy absorption and arresting crack propagation during fracture. Coarse and deep dimples associated with obvious recrystallization underneath were detected in the fracture surfaces, owing to the presence of the nanotwin bundles. The enhancement of fracture toughness is closely correlated with the formation of these deep dimples. (C) 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.