Article
Polymer Science
Huagao Fang, Xingchen Gao, Fan Zhang, Wenjuan Zhou, Guobin Qi, Kai Song, Sheng Cheng, Yunsheng Ding, H. Henning Winter
Summary: This study introduces the vitrimer chemistry of boronic transesterification into a triblock thermoplastic elastomer, enabling associative bond exchange in its nanoscale domains. The localized dynamic cross-linking improves the material's creep resistance and allows for reprocessing. The study also explores the potential application of the elastomer as a hot-melt adhesive, showing excellent lap shear strength.
Article
Engineering, Manufacturing
Mio Sato, Kodai Hasegawa, Jun Koyanagi, Ryo Higuchi, Yuichi Ishida
Summary: A viscoelastic/plastic constitutive equation was proposed for viscoelastic media based on irreversible thermodynamics and viscoelastic theory. Uniaxial tensile tests on TriA-X polyimide resin at different temperatures and strain rates were conducted to determine material parameters. The proposed equation was applied to matrix resin using the FORTRAN programming language for numerical analysis, and transverse tensile failure analysis was performed on unidirectional CFRP under constant strain rate condition.
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
(2021)
Article
Engineering, Multidisciplinary
Shahriar Dastjerdi, Amin Alibakhshi, Bekir Akgoz, Omer Civalek
Summary: This research proposes a comprehensive theoretical method to predict the mechanical behavior of materials with nonlinear elastic deformations. It is important for the design of complex engineering structures and can serve as a reference for researchers studying nonlinear elastic structures.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2022)
Article
Mechanics
Dongdong Chen, Xiaoyu Sun, Shoune Xiao, Guangwu Yang, Bing Yang, Tao Zhu, Mingmeng Wang
Summary: This study investigated the energy-absorbing mechanisms of composite structures subjected to quasistatic and dynamic axial crushing loads. Double hat-shaped composite tubes made of CFRP and GFRP were tested and analyzed. Results showed that the CFRP structures had reduced energy absorption at higher loading rates, while the GFRP structures remained relatively constant. A finite element model considering strain rate effects accurately predicted the crushing behavior. Mechanical properties of the composite materials played a critical role in the distinct responses of CFRP and GFRP structures. The findings contribute to the crashworthiness design of composite energy-absorbing structures.
COMPOSITE STRUCTURES
(2023)
Article
Engineering, Manufacturing
Naveen Thirunavukkarasu, Jianhong Gao, Shuqiang Peng, Abdelatif Laroui, Lixin Wu, Zixiang Weng
Summary: This study improved the mechanical performance of lattice structures through hybrid grading design and employed vat photopolymerization-based 3D printing technique for fabrication. The results showed that the hybrid design exhibited better mechanical performance than the uniform lattice under high load conditions, and the introduction of filler further enhanced stiffness and reduced buckling.
ADDITIVE MANUFACTURING
(2023)
Article
Engineering, Electrical & Electronic
Jungjin Park, Young T. Choi, Alison B. Flatau, Norman M. Wereley
Summary: In this study, magnetorheological fluid (MRF) was encapsulated in a 3-D printed elastomeric cellular structure. The effects of external magnetic fields and excitation frequencies on the mechanical properties of the material were investigated.
IEEE TRANSACTIONS ON MAGNETICS
(2022)
Article
Chemistry, Analytical
Jeeeun Kim, Changsoon Choi
Summary: Motion sensing, particularly in the field of detecting and monitoring mechanical deformation, has attracted significant attention. Fiber-structured mechanical strain sensors with carbon-based materials have emerged as promising alternatives for wearable applications. This study successfully developed multi-modal strain sensors that can monitor multiple deformations.
Article
Materials Science, Multidisciplinary
Chen Wang, Gaurav Chaudhary, Randy H. Ewoldt, Ralph G. Nuzzo
Summary: The research team successfully fabricated structures with high shape retention at smaller scales using a novel particle-free conductive emulsion ink, achieving complex 3D feature dimensions previously impossible. The printability and post-treatment properties of the ink were evaluated, providing a new approach for applications in soft microelectronics.
ADVANCED ENGINEERING MATERIALS
(2022)
Article
Engineering, Mechanical
D. Chen, H. Wu, Q. Fang, J. Wei, S. L. Xu
Summary: This study investigates the hyperelastic and viscoelastic behaviors of spray polyurea (SPUA) and its application in numerical simulations under impact and blast loadings. A nonlinear viscohyperelastic constitutive model is established and validated, and a simplified rubber/foam model is selected to describe the mechanical behavior of SPUA. The study provides a helpful reference for the design and evaluation of SPUA retrofitted structures.
INTERNATIONAL JOURNAL OF IMPACT ENGINEERING
(2022)
Article
Engineering, Civil
Nejc Novak, Shigeru Tanaka, Kazuyuki Hokamoto, Anja Mauko, Yunus Emre Yilmaz, Oraib Al-Ketan, Matej Vesenjak, Zoran Ren
Summary: In this study, four different geometries of uniform triply periodic minimal surface cellular structures were fabricated and tested under different compressive strain rates. The deformation behavior and energy absorption capacity of these structures changed with different strain rates. Computational models were also developed to predict the behavior of these structures at higher strain rates, and it was found that the Diamond and IWP structures exhibited higher energy absorption capacity.
THIN-WALLED STRUCTURES
(2023)
Article
Chemistry, Physical
Claudio Giorgi, Angelo Morro
Summary: This paper presents a general scheme for viscoelastic materials, introducing entropy production as a constitutive function to expand the range of models. The scheme allows for obtaining nonlinear models of thermo-viscoelastic materials subject to large deformations, including various special cases of viscoelastic and heat conduction models.
Article
Engineering, Manufacturing
Xincheng Wang, Yaokai Tang, Shangru Cheng, Qiangmin Gao, Yingxin Yuan, Anqi Li, Shanshan Guan
Summary: In this study, a flexible strain sensor based on a novel reduced graphene oxide/polydimethylsiloxane (rGO/PDMS) conductive elastomeric composite with a 3D conductive network was developed using latex assembly technique for the first time. The exclusive volume effect of the latex particles allowed selective distribution of rGO in the interstitial spaces, resulting in the formation of a 3D conductive network with an ultralow amount of rGO (0.44 vol%), making the rGO/PDMS composites mechanically robust and flexible. Each PDMS latex particle acted like an elastic balloon, aiding the destruction and reconstruction of the conductive network under external stimulus, thus providing excellent sensitivity to the sensor. The strain sensors exhibited superior sensitivity (44.01), a wide strain range (300%), and good stability (2500 cycles), enabling effective detection of human finger movements, facial muscles, voice recognition, and physiological signals.
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
(2022)
Article
Engineering, Civil
P. Areias, F. Q. de Melo, J. N. Sikta
Summary: The study investigates the zero-stress constraints in thin-walled structures and discusses the coupling of stress and strain, utilizing a specific equation arrangement to describe the system. By developing a thin-walled implicit integrator, the issues under any hyperelastic case and yield function are addressed.
THIN-WALLED STRUCTURES
(2022)
Article
Engineering, Multidisciplinary
Sergei Khakalo, Anssi Laukkanen
Summary: This study combines Mindlin's strain gradient elasticity theory and Gudmundson-Gurtin-Anand strain gradient plasticity theory to form a unified framework, enriching the modeling capabilities by including the gradient of elastic strains. Numerical results show that the elastic length scale parameter controls the slope of the elastic part and causes additional hardening in the plastic part of the material response curves.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2022)
Article
Materials Science, Characterization & Testing
Yingyu Wang, Jichong Wang, Xiongqi Peng
Summary: A refined 3D finite strain viscoelastic constitutive model for thermally induced shape memory polymers is proposed, reducing the number of material parameters from seventeen to thirteen and simplifying the parameter identification process, leading to improved accuracy and applicability of the model.
Article
Pediatrics
Jeyapal Kandasamy, Peter S. Theobald, Ian K. Maconochie, Michael D. Jones
ARCHIVES OF DISEASE IN CHILDHOOD
(2019)
Article
Engineering, Manufacturing
Quanquan Han, Yuchen Gu, Rossitza Setchi, Franck Lacan, Richard Johnston, Sam L. Evans, Shoufeng Yang
ADDITIVE MANUFACTURING
(2019)
Article
Materials Science, Multidisciplinary
Scott Townsend, Rhosslyn Adams, Michael Robinson, Benjamin Hanna, Peter Theobald
MATERIALS & DESIGN
(2020)
Article
Engineering, Manufacturing
Shwe Soe, Rhosslyn Adams, Mokarram Hossain, Peter Theobald
Summary: This study evaluates a novel fluid-filled, closed-cell lattice structure as a means to reduce peak acceleration in impact environments. The findings demonstrate that water infill can improve impact performance at higher energies, and solid modeling is the only viable solution for achieving structural densification.
ADDITIVE MANUFACTURING
(2021)
Article
Engineering, Mechanical
Henrique Ramos, Rafael Santiago, Shwe Soe, Peter Theobald, Marcilio Alves
Summary: This paper investigates the impact performance of gyroid lattice structures through experiments and analysis. The study finds that changes in the gyroid isosurface topology have a significant influence on its impact performance.
INTERNATIONAL JOURNAL OF IMPACT ENGINEERING
(2022)
Article
Engineering, Mechanical
Benjamin Hanna, Rhosslyn Adams, Scott Townsend, Michael Robinson, Shwe Soe, Matthew Stewart, R. Burek, Peter Theobald
Summary: This study explored a metamaterial based on the Miura Ori folding pattern as an alternative structure for increased energy absorption in American football helmets, showing promising results in reducing linear accelerations compared to traditional elastomeric foam solutions. The use of novel deformation mechanics and the Taguchi method in evaluating 81 potential structural variations could pave the way for future research and development in protective sports equipment design.
INTERNATIONAL JOURNAL OF IMPACT ENGINEERING
(2021)
Article
Engineering, Mechanical
Rhosslyn Adams, Scott Townsend, Shwe Soe, Peter Theobald
Summary: Finite element simulation was used to analyze the response of an elastomeric pre-buckled honeycomb structure under impact loading, and an optimization method was conducted to identify optimal configurations for impact protection in helmets. The numerical results showed that the optimized structure exceeds the common helmet design standard in performance and injury prevention, establishing a new class of energy absorbing structure.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2022)
Article
Materials Science, Multidisciplinary
Rhosslyn Adams, Scott Townsend, Shwe Soe, Peter Theobald
Summary: Selective laser sintering was used to manufacture different structural variations of a pre-buckled circular honeycomb, and the mechanical behavior of these structures under both quasistatic and dynamic impact loading was examined. It was found that the aspect ratio of the honeycomb could be adjusted to yield different mechanical responses, but this also affected the characteristic stress-softening response of traditional honeycombs. A stabilized response was observed when subjected to multiple cycles of loading, and the numerical models closely matched the experimental results. A simplified periodic boundary condition model provided a faster computational solution.
MATERIALS & DESIGN
(2022)
Article
Engineering, Biomedical
Faizan Ahmad, Shwe Soe, Julie Albon, Rachel Errington, Peter Theobald
Summary: This study aimed to investigate the biomechanical and microstructural changes in cardiac tissue during growth and remodeling. Through testing and analysis of porcine ventricular tissue from neonatal to adulthood, it was found that the tissue exhibited nonlinear, anisotropic, and viscoelastic behavior. Additionally, there were increases in cardiomyocyte rotation and dispersion with age. These findings are important for the development of more accurate computational simulation models.
ACTA BIOMATERIALIA
(2023)
Article
Instruments & Instrumentation
Rhosslyn Adams, Shwe Soe, Peter Theobald
Summary: Advancements in computational modeling and additive manufacturing have enabled the development of helmet liners with superior performance compared to current materials. This study utilizes a finite element-based optimization method to improve cellular structures for helmet impact conditions. The results demonstrate that the optimized pre-buckled honeycomb liner surpasses the performance of contemporary materials in terms of computed kinematic metrics and rotational injury criteria.
SMART MATERIALS AND STRUCTURES
(2023)
Article
Chemistry, Applied
Sotirios Konomou, Miroslav Hadnadev, Aristea Gioxari, Olawoyin Rantimi Abosede, Shwe Soe, Alexandros Ch. Stratakos
Summary: This study aimed to develop a nutritious meal for dysphagia patients using 3D printing technology. The addition of different thickeners was found to affect the texture and rheological behavior of the meal, and the formulations were classified into different levels of dysphagia diet according to international standards.
FOOD HYDROCOLLOIDS
(2024)
Article
Engineering, Manufacturing
Przemyslaw Golebiewski, Pawel Wienclaw, Jaroslaw Cimek, Pawel Socha, Dariusz Pysz, Adam Filipkowski, Grzegorz Stepniewski, Olga Czerwinska, Ireneusz Kujawa, Ryszard Stepien, Rafal Kasztelanic, Andrzej Burgs, Ryszard Buczynski
Summary: We report the development of a 3D printing process for producing soft glass optical fibers. The process involves direct printing using a miniaturized crucible and depositing straight horizontally-oriented lines to replace traditional assembly techniques. Experimental results demonstrate good performance of the printed photonic crystal fiber preform.
ADDITIVE MANUFACTURING
(2024)
