Article
Polymer Science
Mujib Ur Rahman, Yonghao Xi, Haipeng Li, Fei Chen, Dongjie Liu, Jinjia Wei
Summary: This study investigated the stability/instability behavior of polystyrene (PS) films of different thickness on silicon substrates, revealing factors such as effective viscosity, solvent strength, and various interactions on the substrate surface that affect the decrement in residual film thickness, growth of holes in the film, and film dewetting. The results showed that the polarity of the rinsing solvent, film thickness, and substrate type impacted the behavior of the polymer film, highlighting the importance of polymer-substrate interactions in determining the overall stability of the PS thin films.
Article
Materials Science, Multidisciplinary
Aleksandr Lenshin, Pavel Seredin, Dmitry Goloshchapov, Ali O. Radam, Andrey Mizerov
Summary: For the first time, this study demonstrates the advantages of using a compliant hybrid substrate of porSi/SiC for growing high-quality ultra-thin nanostructured AlxGa1-xN/GaN heterostructures using molecular beam epitaxy. The experimental and computational data obtained in this work are important for understanding the physics and technology of AlxGa1-xN/GaN nanoheterostructures and their potential applications in optoelectronics.
Article
Chemistry, Multidisciplinary
Jonas Hubertus, Sipontina Croce, Julian Neu, Stefan Seelecke, Gianluca Rizzello, Guenter Schultes
Summary: This report presents a new direct and maskless method for patterning compliant metallic electrodes for dielectric elastomer (DE) applications. Nickel-based electrodes with high conductivity and stretchability are sputter deposited onto pre-stretched membranes, resulting in a wrinkled surface. Using an ultra-short pulse laser system with a wavelength of 355 nm, an arbitrary electrode design can be directly patterned onto the double-sided coated DE membrane, allowing simultaneous ablation of both electrodes and selective ablation of specific electrodes. The laser structuring method enables the manufacturing of miniaturized DE transducers and the integration of optical features into DE electrodes.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Martin Kuczyk, Martin Zawischa, Tim Kruelle, Jan Vollhueter, Stefan Zeiler, Michael Leonhardt, Joerg Kaspar, Otmar Zimmer, Mathias Goeken, Christoph Leyens, Martina Zimmermann
Summary: In this study, in situ tensile testing and micro-cantilever experiments were performed on four high entropy nitride coatings inside a scanning electron microscope to determine their fracture toughness. The results showed a promising combination of high hardness and fracture toughness for the tested coatings.
Article
Multidisciplinary Sciences
Liangliang Zhu, Haozhi Yuan, Kai Wu, Xueru Wang, Gang Liu, Jun Sun, Xiangbiao Liao, Xi Chen
Summary: The study investigates a unique instability mechanism of buckle delamination in a closed thin film weakly bonded to spherical substrates, resulting in a periodic pattern of delaminated hexagonal dimples. This new discovery opens up new possibilities for surface microfabrication with controllable features.
Article
Engineering, Mechanical
Xiuli Xue, Chaofeng Zeng, Shibin Wang, Linan Li
Summary: The mechanical behavior of copper films and copper/chromium bilayer films deposited on polymer substrates was investigated. The results showed that the film shape, crack density, and crack spacing were closely related to the film material and thickness. The chromium interlayer had an influence on the cracking behavior of the copper film. In addition, the crack density of the film was found to be related to the loading rate.
SURFACE TOPOGRAPHY-METROLOGY AND PROPERTIES
(2022)
Article
Materials Science, Ceramics
Yoon Hyung Keum, Jong Yeog Son
Summary: We investigated the ferroelectric switching dynamics, as well as the multiferroic and piezoelectric properties of highly a-oriented epitaxial Bi5Ti3FeO15 (BTFO) thin films on Nb-doped SrTiO3 single crystal substrates. The highly a-oriented epitaxial BTFO thin films exhibited the best ferroelectric properties, while the highly c-oriented epitaxial BTFO thin films exhibited the best ferromagnetic properties. Particularly, the BTFO thin films with a proper mix of a- and c-oriented crystallinity showed the best piezoelectric properties.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2023)
Article
Physics, Fluids & Plasmas
Souradip Chattopadhyay, Akshay S. Desai, Amar K. Gaonkar, Anandamoy Mukhopadhyay
Summary: We investigate the behavior of a thin liquid film flowing over a thin compliant substrate. Breaking the time-reversal symmetry introduces significant effects of the odd component of the Cauchy stress tensor, which have not been explored before. By employing the long-wave theory, we derive equations that couple the film's thickness and the compliant substrate, including considerations of inertia, damping effects, wall tension, and odd viscosity. Our linear stability analysis reveals that the compliant substrate destabilizes the system, while the odd viscosity significantly stabilizes it. Additionally, we employ a weakly nonlinear approach and derive the Kuramoto-Sivashinsky equation from the coupled long-wave equations. Remarkably, incorporating the odd viscosity tensor component can prevent chaotic behavior in compliant substrates under the weakly nonlinear limit. Numerical simulations demonstrate remarkable effects of odd viscosity on substrate deflection, and our numerical investigation of the coupled long-wave equations confirms the consistency of the linear and weakly nonlinear theories with the numerical results.
PHYSICAL REVIEW FLUIDS
(2023)
Article
Materials Science, Multidisciplinary
Christine Jamin, Apurv Dash, Nachiketa Mishra, Rajendra K. Bordia, Olivier Guillon
Summary: The sintering behavior of ring-shaped alumina films on different substrates was investigated, and the interfacial friction parameter played a key role in determining the slip distance of the free edge, thus influencing the opening and closing of the inner hole.
Article
Materials Science, Coatings & Films
Edyta Kobierska, Stanislav Zak, Sabrina Hirn, Megan J. Cordill, Robert Franz, Marisa Rebelo de Figueiredo
Summary: In this study, the tribological properties of Mo films deposited on polyimide substrates were assessed using the ball-on-disc test. The wear mechanisms and induced stresses were analyzed by microscopy and simulation, providing insights into the tribological response of metallic films on compliant substrates.
SURFACE & COATINGS TECHNOLOGY
(2022)
Article
Mechanics
Ryan H. Allaire, Linda J. Cummings, Lou Kondic
Summary: This study focuses on the evolution of a free-surface thin film on a thermally conductive substrate exposed to an external heat source. Thermal effects play a crucial role in the metal film evolution, while the Marangoni effect is found to be insignificant in the considered set-up.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Materials Science, Multidisciplinary
G. A. Ramirez, A. E. Moya Riffo, J. E. Gomez, D. Goijman, L. M. Rodriguez, D. Fregenal, A. Butera, J. Milano
Summary: This study investigates the magnetoelastic behavior of Fe1-xGax thin films grown on glass and oxidized Si(100) amorphous substrates. It was found that the magnetoelastic response is larger for samples on glass compared to those on Si(100), and the response increases with higher concentrations of Ga for both substrates. Additionally, increasing substrate temperature during growth does not significantly affect the magnetoelastic behavior of samples on Si(100). The experimental behavior is well described by a model that considers elastic grain interaction for isotropic systems.
Article
Engineering, Environmental
Boxiao Li, Jun Li, Dongkai Ni, Songsong Tang, Juncheng Fan, Kaiyuan Shi, Zhen Li, Jian Zhou
Summary: Using a liquid substrate for thin-film processing provides advantages in controlling the system conditions and achieving high-performance films. We developed a liquid-substrate-based spontaneous spreading technology that allows for the formation of polymer thin films on liquid substrates with nanometer to micrometer thicknesses, providing a simple route to control the geometry.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Seong Won Kim, Sangsik Park, Siyoung Lee, Daegun Kim, Giwon Lee, Jonghyun Son, Kilwon Cho
Summary: Researchers have successfully developed a stretchable high-performance organic semiconductor thin film by patterning and pinning a polymer semiconductor solution on an elastomeric substrate. This thin film exhibits superior stretchability and charge transport performance, making it suitable for applications in soft electronics.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Tao Zhang, Qian Cheng, Yifan Li, Zhiguo Hu, Yuxuan Zhang, Jinbang Ma, Yixin Yao, Yan Zuo, Qian Feng, Yachao Zhang, Hong Zhou, Jing Ning, Chunfu Zhang, Jincheng Zhang, Yue Hao
Summary: In this study, beta-(AlxGa1-x)(2)O-3 films were deposited on c-plane sapphire substrates using metal-organic chemical vapor deposition. It was found that by adjusting the TMAI flow rate or TMAI/(TMAI + TEGa) flow rate ratio, the diffraction peaks and optical band gap of the films could be modified. Furthermore, the deposition temperature also affected the crystal structure and optical properties of the films.
CRYSTAL GROWTH & DESIGN
(2022)
Article
Materials Science, Multidisciplinary
Baihong Chen, Changyue Liu, Zengting Xu, Zhijian Wang, Rui Xiao
Summary: In this study, both polydomain and monodomain liquid crystal elastomers (LCEs) were synthesized and their shape change with temperature under a certain stress level was characterized. A thermo-order-mechanical coupling model was developed to predict the shape change of LCEs, showing good consistency with experimental results.
MECHANICS OF MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
Peng Wang, Fei Xu, Yiding Wang, Jun Song, Cheng Chen
Summary: This study investigates the interplay of super-screw dislocations and coherent twin boundary (CTB) in Ni3Al using molecular dynamics simulations and dislocation continuum theory. Various interaction mechanisms are observed depending on the stress and dislocation gliding pathways. A continuum model framework is developed to evaluate the critical shear stress required for CTB to accommodate dislocations along different pathways, considering the effects of anti-phase boundary (APB) and Complex Stacking Fault (CSF). The study suggests that the resistant force of CTB against all gliding dislocations is a more appropriate metric for quantifying its strength.
MECHANICS OF MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
Chenyu Du, Haitao Cui, Hongjian Zhang, Zhibin Cai, Weikuo Zhai
Summary: A thermal-elastoplastic phase field model was developed to simulate thermal fatigue crack growth. The accuracy and availability of the model were verified through typical examples. The results indicate that the proposed model effectively simulates the process of thermal fatigue crack propagation in elastoplastic solids. The appropriate regularization length needs to be determined based on experimental results.
MECHANICS OF MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
J. Carlsson, A. Kuswoyo, A. Shaikeea, N. A. Fleck
Summary: The sensitivity of the compressive strength of a polymeric Kelvin lattice to the presence of an epoxy core is investigated both experimentally and numerically. The study shows that the epoxy core prevents the formation of crush bands in the lattice and changes its deformation mode. At finite strain, the strength of the lattice is degraded by bending failure and cracking of the struts and adjacent core, leading to the formation of vertical fissures.
MECHANICS OF MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
Saptarshi Paul, Anurag Gupta
Summary: In this study, we investigate the geometry and mechanics of the buckled orthotropic von Karman elastic plate with free boundary condition, in the presence of an isolated positive or negative disclination. The shape of the buckled plate is cone-like for a positive disclination and saddle-like for a negative disclination. With increasing orthotropy, the shape of the buckled plate becomes more tent-like and the Gaussian curvature spreads along the ridge of the tent. The stress fields are focused in the neighborhood of the defect point and the ridge, indicating that most of the stretching energy is accommodated in these singular regions.
MECHANICS OF MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
Antu Acharya, Vikram Muthkani, Anirvan DasGupta, Atul Jain
Summary: This study proposes filler-based and infill-based strategies for creating auxetic lattices with enhanced stiffness. The elastic properties of the sinusoidal re-entrant honeycomb lattice are developed and validated using finite element models. Parametric studies are conducted to find combinations leading to enhanced stiffness with minor loss in auxeticity. The results demonstrate the possibility of achieving a significant increment in stiffness while retaining significant auxeticity. The proposed approaches outperform existing approaches in terms of stiffness and auxeticity.
MECHANICS OF MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
Biswajit Pal, Ananth Ramaswamy
Summary: This study presents a multi-scale approach to simulate the shrinkage and creep of concrete, addressing the limitations of existing macroscopic prediction models due to the heterogeneous nature of concrete. The model is validated with experimental data and compared to national codes and macroscopic models, demonstrating its effectiveness in overcoming the gaps in existing models.
MECHANICS OF MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
Akash Kumar Behera, Mohammad Masiur Rahaman, Debasish Roy
Summary: Ceramics have attractive properties but low fracture toughness is a major drawback. There is interest in improving the mechanical performance of ceramics by tailoring residual stresses. However, there is a lack of computational models that can accurately predict crack paths and quantify the improved fracture toughness.
MECHANICS OF MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
Bineet Kumar, Sandeep Kumar Dubey, Sonalisa Ray
Summary: This study aims to develop an energy-based theoretical formulation for predicting the evolution of the fracture process zone in concrete under fatigue loading. Experimental results and calibrations indicate that the specimen size and aggregate size affect the fracture behavior and process zone length of concrete.
MECHANICS OF MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
Zheliang Wang, Hao Sheng, Xinyi Lin, Yifan Rao, Jia Liu, Nanshu Lu
Summary: In this study, an analytical framework is proposed for investigating the behavior of laminated beams with any number of layers under various bending conditions, and the theory is validated through finite element analysis. It was found that the number of layers, applied deformation, layer properties, and layer aspect ratio have an impact on the equivalent flexural rigidity.
MECHANICS OF MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
Michael Schwaighofer, Markus Konigsberger, Luis Zelaya-Lainez, Markus Lukacevic, Sebastian Serna-Loaiza, Michael Harasek, Florian Zikeli, Anton Friedl, Josef Fussl
Summary: In this study, nanoindentation relaxation tests were re-evaluated on five industrial lignins extracted from different feedstocks. It was found that the viscoelastic properties of all tested lignins were practically identical and independent of the feedstock and the extraction processes.
MECHANICS OF MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
Tian Han, Dandan Qi, Jia Ma, Chaoyang Sun
Summary: In this study, a generative design method was used to propose new modified lattice structures suitable for tensile and compressive loading conditions. By conducting experimental and finite element analyses, it was confirmed that the derived structures have improved load-bearing capacity and energy absorption compared to the original structures. The effects of shape parameters on mechanical properties were also discussed.
MECHANICS OF MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
Wenbin Zheng, Jay Airao, Ramin Aghababaei
Summary: Spinodal decomposition of Ti1-xAlxN crystal structure significantly affects their physical properties. This study uses three-dimensional molecular dynamics simulations to investigate the phase transformation mechanism and surface finish during material removal in TiAlN. The simulations reveal that the aluminum content and cutting depth have a significant influence on the phase transformation process through spinodal decomposition.
MECHANICS OF MATERIALS
(2024)
Article
Materials Science, Multidisciplinary
Atasi Ghosh
Summary: The micro-mechanism of low cycle fatigue deformation behavior has been summarized and the recent development in the approach of numerical simulation of cyclic stress-strain behavior of polycrystalline metallic materials at multi-scale has been discussed.
MECHANICS OF MATERIALS
(2024)