Article
Chemistry, Physical
Bangqi Yin, Xiangyi Xue, Mengqi Zhang, Taiqing Deng, Jinshan Li, Bin Tang
Summary: Load-displacement curves of gamma and B2 phases in TNM alloy were obtained from nanoindentation experiments and CPFE simulations, showing good consistency and small hardness error. The pileup morphology around indents was discussed based on nanoindentation tests and CPFE simulation, and its relationship with slip behavior and dislocation movement was analyzed. The results indicate that Schmid factors and dislocation movement significantly influence the pileup profile, affecting the flow ability of the material.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Nanoscience & Nanotechnology
Bangqi Yin, Xiangyi Xue, Bin Tang, William Yi Wang, Hongchao Kou, Jinshan Li
Summary: Nanoindentation experiments and crystal plasticity simulations were combined to investigate the deformation behavior and hardness characteristics of the alpha 2 phase in Ti-43.5Al-4Nb-1Mo-0.1B alloy. The results showed a correlation between crystal orientation and hardness, with slip behavior being influenced by Schmid factors.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
Javier Varillas, Jan Ocenasek, Jordi Torner, Jorge Alcala
Summary: Nanoindentation experiments in various metals show the onset of plastic instabilities, formation of permanent nanoimprints and defect networks. Molecular dynamics simulations reveal the processes governing contact resistance, abrupt plastic instabilities, and the evolution towards a steady-state with plateauing hardness. The ratio of hardness to Young's modulus varies between different metals, with BCC Ta and Fe showing higher values. Factors such as stacking faults, nanotwin interlocking, and defect remobilization events contribute to the formation of permanent nanoimprints. Additionally, the correlation between nanoimprint formation and material response to indentation influences the hardness to yield strength ratio, exceeding the continuum plasticity bound.
Article
Physics, Fluids & Plasmas
David Kurunczi-Papp, Lasse Laurson
Summary: The study investigates strain-controlled plastic deformation of crystalline solids using two-dimensional discrete dislocation dynamics simulations. It was found that the dislocation system is sensitive to strain rate and driving spring stiffness. Under low strain rate and spring stiffness conditions, the dislocation avalanches follow a power law distribution with temporally asymmetric average shapes.
Article
Chemistry, Multidisciplinary
Pham T. N. Nguyen, Fazilay Abbes, Jean-Sebastien Lecomte, Christophe Schuman, Boussad Abbes
Summary: This paper investigates the orientation-dependent characteristics of pure zinc under localized loading using nanoindentation experiments and crystal plasticity finite element (CPFEM) simulations. The proposed approach combines the response surface methodology together with a genetic algorithm to determine an optimal set of parameters.
Article
Nanoscience & Nanotechnology
Yilun Xu, Tianhong Gu, Jingwei Xian, Finn Giuliani, T. Ben Britton, Christopher M. Gourlay, Fionn P. E. Dunne
Summary: The mechanical properties and temperature sensitivity of beta-Sn single crystals and polycrystalline beta-Sn-rich alloys have been investigated using a combination of experimental and numerical methods. The results provide insights into the behavior of electronic solders under thermomechanical loading.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Metallurgy & Metallurgical Engineering
H. Wang, X. Sun, S. Kurukuri, M. J. Worswick, D. Y. Li, Y. H. Peng, P. D. Wu
Summary: Manufacturers have developed magnesium alloys with remarkable properties by adding rare-earth elements to overcome the limitation in formability at room temperature. The rare-earth magnesium alloys behave differently from conventional alloys, especially in terms of their anisotropic and strain rate sensitive behavior. This study investigates the behavior of a rare-earth Mg alloy ZEK100 sheet at room temperature using an elastic viscoplastic self-consistent polycrystal plasticity model. Different strain rate sensitivities are employed by the model to simulate the strain rate sensitive behaviors under different loading directions and rates. The study highlights the importance of using different strain rate sensitivities for each deformation mode in hexagonal close-packed metals.
JOURNAL OF MAGNESIUM AND ALLOYS
(2023)
Article
Engineering, Mechanical
Masato Wakeda, Ya-Ling Chang, Seiichiro Ii, Takahito Ohmura
Summary: The study evaluated the dislocation-grain boundary interactions in polycrystalline metals using experimental and computational nanoindentation analyses. The results from experiments and simulations provided insights into the plastic zone formation, dislocation nucleation, and transmission behavior at different GB interfaces. The findings highlighted the importance of GB structure and stress in influencing the strengthening mechanism of metals.
INTERNATIONAL JOURNAL OF PLASTICITY
(2021)
Article
Engineering, Mechanical
Wenbo Zhu, Guangjian Yuan, Jianping Tan, Shuai Chang, Shantung Tu
Summary: This study investigates the nanoindentation behavior of Inconel 718 polycrystalline material using a three-dimensional CPFEM simulation. The results show that the crystallographic orientation and grain boundary have little influence on the nanoindentation force-displacement curves, but significantly influence the local stress distributions and shape of the pile-up patterns. The existence of grain boundaries also affects the continuity of the stress distribution, with a larger grain boundary angle resulting in greater obstruction.
CHINESE JOURNAL OF MECHANICAL ENGINEERING
(2023)
Article
Materials Science, Multidisciplinary
Gerald J. K. Schaffar, Daniel Tscharnuter, Verena Maier-Kiener
Summary: This study investigates the mechanical behavior of silicon at different temperatures using nanoindentation experiments. It was found that there is a change in deformation behavior between 300℃ and 400℃, shifting from high-pressure phase transformation to dislocation-controlled plasticity with increasing temperature. Additionally, above 800℃, there is a further shift in the rate-controlling mechanism of dislocation motion.
MATERIALS & DESIGN
(2023)
Article
Engineering, Mechanical
X. D. Zan, X. Guo, G. J. Weng, G. Chen
Summary: The precipitation of zirconium hydride reduces the fracture toughness of nuclear reactor fuel cladding tube. Due to experimental difficulties, numerical approaches are needed to gain a deep understanding of the mechanical properties of zirconium hydride. A crystal plasticity finite element model is used to simulate the nanoindentation deformation behavior of single-crystal 6-hydride, and the parameters in the model are calibrated by experimental data. The simulation results show good agreement with experimental results and reveal the dependency of nanoindentation hardness on indentation depth and crystallographic orientation.
INTERNATIONAL JOURNAL OF PLASTICITY
(2023)
Article
Materials Science, Multidisciplinary
Patrick Feldner, Benoit Merle, Mathias Goeken
Summary: The study analyzed the deformation behavior of ultrafine-grained, heterogeneous superplastic alloy at small scales and found new characteristics of strain rate sensitivity, emphasizing the importance of controlling grain boundary sliding by dislocation creep.
MATERIALS RESEARCH LETTERS
(2021)
Article
Engineering, Mechanical
Liangwei Yin, Osamu Umezawa
Summary: This study investigates the temperature-dependent dwell fatigue behavior of Ti-6Al-4V alloy using crystal plasticity finite element method. The results show that the variation of strain rate sensitivity with temperature influences the stress redistribution and dwell fatigue sensitivity.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Nanoscience & Nanotechnology
Francisco-Jose Gallardo-Basile, Franz Roters, Robin M. Jentner, James P. Best, Christoph Kirchlechner, Kinshuk Srivastava, Sebastian Scholl, Martin Diehl
Summary: This paper presents the application of an inverse method to determine the crystal plasticity constitutive law parameters for a body-centered-cubic (BCC) single phase material. Nanoindentation is used as the main experimental input, and a differential evolution algorithm is employed to minimize the objective function based on the deviation between the experimentally measured imprint and the simulated one. Additional experimental data from micropillar compression experiments is used as a constraint to assist the identification procedure. The method is validated by comparing experimental tensile tests with simulated ones using the obtained crystal plasticity parameters, showing accurate results from two different indents. Therefore, this method is promising for determining crystal plasticity parameters in multi-phase materials where direct fitting from a macroscopic stress-strain curve is not possible.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Chemistry, Multidisciplinary
Mangalampalli S. R. N. Kiran, Manish Kumar Mishra, Upadrasta Ramamurty
Summary: Nanoindentation experiments were conducted on several molecular crystals to measure the load at which elastic-to-plastic transition occurs and determine the activation volume. The results showed a linear relationship between activation volume and molecular size, suggesting a close correlation between plastic deformation and molecular dimensions in molecular crystals.
CRYSTAL GROWTH & DESIGN
(2021)
