Plastic deformation and dissolution of ε-Cu particles by cold rolling in an over-aged particle dispersion strengthening Fe-2mass%Cu alloy
Plastic deformation and dissolution of ε-Cu particles by cold rolling in an over-aged particle dispersion strengthening Fe-2mass%Cu alloy
复制标题
DOI：
10.1016/j.actamat.2016.03.018
复制
发表时间：
2016-07-01
期刊：
影响因子：
9.4
通讯作者：
Takaki, Setsuo
中科院分区：
文献类型：
--
作者：
Tsuchiyama, Toshihiro;Yamamoto, Shinji;Takaki, Setsuo
变形和溶解行为是钢中软弥散颗粒的重要特征，通过控制与颗粒弥散强化相关的加工硬化/软化和断裂过程来改善高强度钢板的变形能力。在这项研究中，研究了铁素体基体中ε-Cu沉淀颗粒的变形和溶解行为，以了解与合金碳化物等硬弥散颗粒相比，相对软的弥散颗粒如何影响钢的机械响应。通过冷轧，直径为35 nm的近球形e-Cu颗粒最初沿轧制方向被拉长，然后随着等效应变的增加，这些颗粒部分溶解到铁素体基体中。 Cu 颗粒的溶解被认为是由于剧烈冷加工锐化的颗粒尖端处的位错剪切导致 Cu 原子从沉淀物动态分配到基体中造成的。同时，冷轧过程中ε-Cu颗粒对弥散强化的贡献似乎随着基体中位错密度的增加而降低。随着变形的进行，ε-Cu 颗粒中的位错密度和其他缺陷也增加，颗粒/基体界面呈锯齿状或变得模糊。参考同样加工的硬质颗粒分散的 Fe-V 二元合金，讨论了细分散颗粒的形貌、内部缺陷和界面结构变化及其与合金机械响应的相关性。 (C) 2016 Acta Materialia Inc. 由 Elsevier Ltd 出版。保留所有权利。
Deformation and dissolution behaviors are important characteristics of soft dispersion particles in steel to improve the deformability of high strength steel sheets by controlling the work hardening/softening and fracture processes associated with particle dispersion strengthening. In this study, the deformation and dissolution behaviors of epsilon-Cu precipitate particles in a ferrite matrix were investigated to understand how relatively soft dispersion particles influence mechanical responses of the steel compared to hard dispersion particles such as alloy carbides. 35 nm diameter nearly spherical e-Cu particles were initially elongated along the rolling direction by cold rolling, and then these were partly dissolved into the ferrite matrix as the equivalent strain increased. The dissolution of the Cu particles was suggested to be caused by a dynamic partitioning of Cu atoms from the precipitates into the matrix by dislocation shearing at the particle tip sharpened by severe cold working. Simultaneously, the contribution of the epsilon-Cu particles to the dispersion strengthening appeared to be decreased with increasing dislocation density in the matrix during cold rolling. The dislocation density and other defects in the epsilon-Cu particles also increased and the particle/matrix interfaces were serrated or became indistinct as deformation progressed. The morphology, internal defects, and interface structure changes of fine dispersion particles and their correlation with mechanical responses of the alloy are discussed in reference to an identically processed, hard particles dispersed Fe-V binary alloy. (C) 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.