Effect of dislocation and grain boundary on deformation mechanism in ultrafine-grained interstitial-free steel

6th International Conference on Nanomaterials by Severe Plastic Deformation

材料科学;化学

Nakazawa, K.^1,3 ; Itoh, S.^1 ; Matsunaga, T.^2 ; Matsukawa, Y.^2 ; Satoh, Y.^2 ; Murase, Y.^3 ; Abe, H.^2

School of Engineering, Tohoku University, Miyagi, Japan^1

Institute for Materials Research, Tohoku University, Miyagi, Japan^2

National Institute for Materials Science, Ibaraki, Japan^3

关键词: Accumulative roll bonding;    Deformation mechanism;    Dislocation densities;    Dislocation motion;    Effect of dislocations;    Grain-boundary slidings;    Interstitial free steel;    Ultra-fine-grained;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/63/1/012125/pdf
DOI  :  10.1088/1757-899X/63/1/012125

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

Ultrafine-grained interstitial-free steel fabricated by the accumulative roll-bonding method was subjected to tensile tests and analyses of AFM, TEM and XRD to identify the effects of interaction between dislocations and grain boundaries (GB) on the deformation mechanism. The AFM analyses indicated that the main deformation mechanism of this material changed from dislocation motion to grain boundary sliding (GBS) with decreasing strain rate. TEM observations and XRD analysis revealed showed that dislocations piled up at GB and the dislocation density decreased with increasing strain. Those suggest the dislocations are absorbed into GB during deformation, activating slip-induced GBS.