Article
Nanoscience & Nanotechnology
P. S. M. Jena, S. K. Pradhan, S. Tripathy, B. Mahato, C. Fernando, N. Paulose, J. K. Sahu
Summary: The study on the evolution of geometrically necessary dislocation density (GND) at the gamma and primary gamma' interface during tensile deformation of turbine disk alloy revealed that GND values were highest at 800 degrees C and lowest at 350 degrees C, primarily due to the gamma/gamma' misfit value. At high temperatures, localized plastic deformation in the gamma-matrix near gamma-gamma' interfaces was identified as the main cause for necking after yielding, as evidenced by higher GND values and grain interior distortion.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Engineering, Mechanical
Sukumar Agaram, Anand K. Kanjarla, Baskaran Bhuvaraghan, Sivakumar M. Srinivasan
Summary: A crystal plasticity model based on dislocation density has been developed to analyze the cyclic softening induced by precipitates in IN718. The model effectively simulates the macroscopic mechanical response under different loading conditions, with predictions showing good agreement with experimental data. Sensitivity analyses were performed to investigate the influence of grain size, reversible dislocations, and precipitate size.
INTERNATIONAL JOURNAL OF PLASTICITY
(2021)
Article
Materials Science, Multidisciplinary
Wenkai Fu, Yulan Li, Shenyang Hu, Peter Sushko, Suveen Mathaudhu
Summary: Through the study of crystal plasticity theory, it was found that in solid phase processing, regions with high misorientation and GND density first appear near grain boundaries and extend towards interior grains. The loading path affects plastic deformation accumulation and recovery, and thus affects dislocation evolution and misorientation.
COMPUTATIONAL MATERIALS SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
C. Zhao, X. Li
Summary: The study characterized deformation of two iron-based alloys, Nitronic 60 and Tristelle 5183, using push-release bend testing, HR-EBSD, and HR-DIC methods. The results showed that high GND densities contributed to work hardening and high residual elastic strain accumulation, while heterogeneous grain/carbide size distribution led to stress concentration, causing carbide decohesion and brittle fracture of the sample.
EXPERIMENTAL MECHANICS
(2021)
Article
Materials Science, Multidisciplinary
Maoyuan Jiang, Benoit Devincre
Summary: The influence of grain orientation on long-range internal stress associated with the accumulation of geometrically necessary dislocations (GNDs) during plastic deformation is numerically investigated. It is found that GNDs stored at grain boundaries (GBs) do not systematically generate a backstress within grains. Surprisingly, accumulation of GNDs at certain GB interfaces leads to the emergence of long-range anti-backstress, promoting dislocation dynamics and plastic strain within the grains. This discovery provides guidelines to improve the physical content of current crystal plasticity models.
COMPUTATIONAL MATERIALS SCIENCE
(2022)
Article
Microscopy
Qi Lu, Jiayi Wu, Shilong Liu, Shiqi Zhang, Xiaorong Cai, Wei Li, Jun Jiang, Xuejun Jin
Summary: A multi-modal deep learning approach is proposed to predict the geometrically necessary dislocation (GND) density in materials. The method utilizes electron backscatter patterns (EBSPs) and dislocation configurations to achieve accurate predictions. The study also introduces a specific data augmentation strategy for the GND prediction task. High accuracy is achieved on aluminum samples, and the networks are robust and capable of real-time analysis.
Article
Nanoscience & Nanotechnology
Nan Wang, Yongnan Chen, Gang Wu, Qinyang Zhao, Zhen Zhang, Lixia Zhu, Jinheng Luo
Summary: This study reveals the different contributions of geometrically necessary dislocation (GND) and statistically stored dislocation (SSD) to work hardening in dual-phase steel. By introducing high-density GND through pre-tensile loading-unloading-reloading (LUR) and high-density SSD through monotonic pre-tensile, it is found that the steel with high GND exhibits higher yield stress and stronger strain hardening ability compared to the high-SSD steel, even with almost the same total dislocation density.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Mechanics
Antoine Lucchetta, Francois Auslender, Michel Bornert, Djimedo Kondo
Summary: This study investigates the behavior of elastoplastic composites with isotropic and nonlinear kinematic hardening by extending the Double Incremental Variational (DIV) formulation. It is found that the Armstrong-Frederick model for describing nonlinear kinematic hardening cannot be handled within the framework of generalized standard materials, leading to the use of the modified Chaboche model as an approximation. The new incremental variational procedure developed in this study shows favorable comparisons with Finite Element simulations based on the Armstrong-Frederick model for various cyclic loadings.
INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES
(2021)
Article
Engineering, Mechanical
Serhat Aygun, Tillmann Wiegold, Sandra Klinge
Summary: The paper proposes a thermodynamically consistent model for simulating ductile damage by coupling fracture phase field method and Armstrong Frederick plasticity model. The model's application is illustrated through numerical examples studying material response under different load cases and geometries, with comparisons made with experimental results.
INTERNATIONAL JOURNAL OF PLASTICITY
(2021)
Article
Materials Science, Multidisciplinary
Sowmya Daroju, Toshihiko Kuwabara, Marko Knezevic
Summary: This paper investigates the monotonic and load reversal deformation of dual-phase and martensitic steel sheets, quantifies the particularities of the reversal deformation and determines related parameters. By using a crystal plasticity model, the experimental data are interpreted and predicted, highlighting the significance of crystallographic slip and dislocation density evolution.
MECHANICS OF MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Xiao Wang, Zhengqing Zhou, Sheng Liu, Mingyu Huang
Summary: This study reveals a significant increase of GND tensor in 316 austenitic steel at the plastic stage, with the largest rise occurring at the early stage and the biggest increase of zero-value point happening later. This suggests that the rapid accumulation of GND density may be a precursor to defects formation or material degradation. The GND tensors can therefore be used for degradation analysis of 316 steel.
Article
Engineering, Mechanical
Yilun Xu
Summary: A non-local method for establishing GND based on a non-local domain integral has been developed and validated, showing improved accuracy in predicting material fatigue life. The comprehensive study on non-local domain effect revealed the necessity of applying the non-local GND method, as it resembles experimental observations and enhances stress field predictions compared to local methods.
INTERNATIONAL JOURNAL OF PLASTICITY
(2021)
Article
Materials Science, Multidisciplinary
Kai Zhang, Xinbao Liu, Ping Fan, Lin Zhu, Kai Wang, Lin Wang, Caili Zhao
Summary: This study investigates the change of geometrically necessary dislocation (GND) during the elevated temperature creep of P91 steel. The results show that the GND density increases significantly during the initial creep stage, reaches a maximum at the transition from initial creep to steady creep, and gradually decreases during subsequent creep. It also demonstrates that the GND density can be used to predict internal stress and analyze microstructure degradation of P91 steel during creep.
MATERIALS CHARACTERIZATION
(2023)
Article
Nanoscience & Nanotechnology
Daniel L. Foley, Marat Latypov, Xingyuan Zhao, Jonathan Hestroffer, Irene J. Beyerlein, Leslie E. Lamberson, Mitra L. Taheri
Summary: It was found that crystal orientation has a significant impact on GND density, with the highest density in grains with a 101 101 compression texture; additionally, grain boundaries play a crucial role as strong dislocation sources in the evolution of GND density.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
Himanshu Joshi, Junyan He, Nikhil Chandra Admal
Summary: Grain boundary processes such as shear coupling and sliding are consequences of plastic distortion during grain boundary motion. This study introduces the concept of disconnections as the primary carriers of grain boundary plasticity, and develops a diffuse-interface finite deformation theory for grain boundary plasticity based on the notion of geometrically necessary disconnections. The proposed model can accurately describe phenomena such as state-dependent shear coupling, mode switching, grain boundary sliding, and grain rotation.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2022)
Article
Construction & Building Technology
Ritwik Bandyopadhyay, Soumyabrata Maiti, Aparna (Dey) Ghosh, Anindya Chatterjee
STRUCTURAL CONTROL & HEALTH MONITORING
(2018)
Article
Acoustics
Soumyabrata Maiti, Ritwik Bandyopadhyay, Anindya Chatterjee
JOURNAL OF SOUND AND VIBRATION
(2018)
Article
Materials Science, Multidisciplinary
Ritwik Bandyopadhyay, John Rotella, Diwakar Naragani, Jun-Sang Park, Michael Eff, Michael D. Sangid
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2019)
Article
Materials Science, Multidisciplinary
Ritwik Bandyopadhyay, Veerappan Prithivirajan, Michael D. Sangid
Article
Materials Science, Multidisciplinary
Ritwik Bandyopadhyay, Michael D. Sangid
Article
Materials Science, Multidisciplinary
Ritwik Bandyopadhyay, Alberto W. Mello, Kartik Kapoor, Michael P. Reinhold, Thomas F. Broderick, Michael D. Sangid
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2019)
Article
Multidisciplinary Sciences
Ritwik Bandyopadhyay, Veerappan Prithivirajan, Alonso D. Peralta, Michael D. Sangid
PROCEEDINGS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES
(2020)
Article
Engineering, Mechanical
Michael Waddell, Kevin Walker, Ritwik Bandyopadhyay, Kartik Kapoor, Alexandra Mallory, Xianghui Xiao, Andrew C. Chuang, Qianchu Liu, Nam Phan, Michael D. Sangid
INTERNATIONAL JOURNAL OF FATIGUE
(2020)
Article
Engineering, Manufacturing
Ritwik Bandyopadhyay, Michael D. Sangid
Summary: This paper presents a probabilistic framework for predicting fatigue life and failure modes, focusing on competing failure modes in nickel-based superalloys. By using accumulated plastic strain energy density to predict fatigue crack initiation, the study characterizes the temperature-dependent variation of critical APSED in RR1000 variants through Bayesian inference. The results provide insights into failure mode prediction, uncertainty quantification in fatigue life, and the temperature-induced changes in failure modes.
INTEGRATING MATERIALS AND MANUFACTURING INNOVATION
(2021)