Article
Instruments & Instrumentation
Yuheng Liu, Ming Lei, Linlong Peng, Haibao Lu, Dong-Wei Shu
Summary: This study designs a 3D printed auxetic structure that achieves a tunable out-of-plane double hyperbolic buckling behavior by varying stiffness across thickness. The influences of radius and draft angle on the buckling behaviors are studied, and the constitutive relationships between stress, strain, radius, and draft angle are discussed. The accuracy of the analytical results is verified by experiment.
SMART MATERIALS AND STRUCTURES
(2022)
Article
Materials Science, Multidisciplinary
Xiaoyang Zheng, Xiaofeng Guo, Ikumu Watanabe
Summary: This study introduces a new 3D auxetic metamaterial generated from an implicit expression, fabricated using 3D printing, and enhanced with a nickel layer for improved performance. Evaluation of the metamaterial's performance through compression tests and finite element analyses, along with contour maps for guidance in functional applications, were presented. Integration of 3D printing and electroless plating allowed accurate control over the mechanical and conduction properties of the material.
MATERIALS & DESIGN
(2021)
Article
Instruments & Instrumentation
Yuheng Liu, Ming Lei, Haibao Lu, Dong-Wei Shu
Summary: This study focuses on the design and 3D printing of an auxetic shape-memory dual-moiety structure, investigating the effects of various factors on its buckling behavior and discussing constitutive relationships between stress, strain, hollowness radius, and Young's modulus. Mechanical tests were conducted to verify the accuracy of numerical results, providing a design guideline for auxetic dual-moiety structures with tunable buckling behaviors through twofold viscoelastic resonances.
SMART MATERIALS AND STRUCTURES
(2021)
Article
Instruments & Instrumentation
Zhenghong Li, Yuheng Liu, Haibao Lu, Dong-Wei Shu
Summary: This study achieves bidirectional hyperbolic out-of-plane deformation and auxetic behavior of thin plates under uniaxial compression by tuning the parameters of horseshoe structures.
SMART MATERIALS AND STRUCTURES
(2022)
Article
Chemistry, Physical
Xinran Zhou, Kaushik Parida, Jian Chen, Jiaqing Xiong, Zihao Zhou, Feng Jiang, Yangyang Xin, Shlomo Magdassi, Pooi See Lee
Summary: The fast development of wearable electronic systems requires a sustainable energy source. Piezoelectric polymer films are a perfect candidate for fabricating nanogenerators, but most of their applications are limited to the pressing mode energy harvesting. In this work, an auxetic structure is 3D printed on a polymer film-based PENG, enabling the bending deformation of the PENG to be transformed into controlled in-plane stretching deformation, increasing the bending output voltage by 8.3 times. The auxetic structure-assisted PENG is also demonstrated as a sensor for bending angle and motion monitoring.
ADVANCED ENERGY MATERIALS
(2023)
Article
Engineering, Mechanical
Amin Montazeri, Ehsan Bahmanpour, Majid Safarabadi
Summary: An innovative mechanical metamaterial with sign-switching stiffness-changing properties and potential applications in the automotive and construction industries is presented in this study. The metamaterial, designed by modifying and combining hexagonal and re-entrant unit cells, is fabricated using additive manufacturing and explored through experiments and finite element analysis. The parametric studies show that the auxeticity and Poisson's ratio sign-changing properties of the material can be tuned by modifying the design parameters. Additionally, the load-carrying capacity and stiffness-changing properties can be adjusted by modifying the unit cell parameters.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2023)
Article
Engineering, Civil
Yiyi Zhou, Yunfan Li, Dan Jiang, Yu Chen, Yi Min Xie, Liang-Jiu Jia
Summary: In this study, drop hammer impact tests and finite element analyses were conducted to investigate the dynamic responses of metallic auxetic honeycombs. The results showed that the auxetic honeycomb specimens had better energy absorption performance, leading to significantly improved energy absorption efficiency.
ENGINEERING STRUCTURES
(2022)
Article
Engineering, Civil
Yading Xu, Branko Savija
Summary: This work proposes a 3D auxetic cementitious-polymeric composite structure (3D-ACPC) that combines 3D printed polymeric shell with cementitious mortar. Experimental results show that the 3D-ACPC has the ability to overcome the brittleness of conventional cementitious material and the low compressive strength of 3D printed polymeric cellular shell, exhibiting compressive strain-hardening behavior and high energy absorption ability. The 3D-ACPC also shows significantly enhanced specific energy absorption compared to conventional cementitious materials and polymeric cellular materials.
ENGINEERING STRUCTURES
(2023)
Article
Materials Science, Multidisciplinary
Lung Chow, Kit-lun Yick, Kam Ho Wong, Matthew Sin-hang Leung, Yue Sun, Mei-ying Kwan, Karolyn Ning, Annie Yu, Joanne Yip, Ying-fan Chan, Sun-pui Ng
Summary: This study proposes the use of 3D printed materials with an auxetic architecture to improve pressure therapy. The results of experiments and numerical calculations demonstrate the stability and pressure adaptability of the auxetic structures under out-of-plane bending, indicating that this design can promote the recovery of HS.
MACROMOLECULAR MATERIALS AND ENGINEERING
(2022)
Article
Instruments & Instrumentation
Amer Alomarah, Zahraa A. Al-Ibraheemi, Dong Ruan
Summary: This study proposes an auxetic stent called RCA, which has controllable auxetic features by adjusting geometric parameters and the number of unit cells. The experimental and numerical results show that the RCA stents have remarkable radial expansion capabilities and exhibit different deformation patterns.
SMART MATERIALS AND STRUCTURES
(2023)
Article
Materials Science, Multidisciplinary
Lei Ren, Wenzheng Wu, Luquan Ren, Zhengyi Song, Qingping Liu, Bingqian Li, Qian Wu, Xueli Zhou
Summary: In this study, a new mechanical metamaterial with programmable mechanical properties was prepared using the high-performance polymer PEEK as the printing material. By combining structural design with the shape memory properties of PEEK, reconfigurable metamaterial structure and properties were achieved.
ADVANCED MATERIALS TECHNOLOGIES
(2022)
Article
Engineering, Mechanical
Anis Hamrouni, Jean-Luc Rebiere, Abderrahim El Mahi, Moez Beyaoui, Mohamed Haddar
Summary: This study investigates the static properties of architectural cores and the dynamic behavior of sandwich structures using an auxetic or non-auxetic core through experimental and numerical analyses. Three types of architectural cores, including re-entrant, rectangular, and hexagonal honeycombs, were studied with varying densities. Tensile tests were conducted to analyze the influence of core topology and density on Poisson's ratio and Young's modulus. Vibration tests were then performed to study the impact of these structures and their densities on the dynamic properties of sandwiches. The results demonstrate a sensitive behavior of the structural Poisson's ratio to core topology and density.
JOURNAL OF SANDWICH STRUCTURES & MATERIALS
(2023)
Article
Chemistry, Physical
Ismael Ben-Yelun, Guillermo Gomez-Carano, Francisco J. San Millan, Miguel Angel Sanz, Francisco Javier Montans, Luis Saucedo-Mora
Summary: The goal of this research is to introduce a novel tunable 3D metamaterial that can reproduce a wide spectrum of 3D auxetic and non-auxetic Poisson's ratios and Young's moduli. By changing the connectivity and position of the cell's internal nodes, this metamaterial can accommodate different spatial curvatures and boundaries. This wide range of variation is achieved through simple spatial triangularization and allows for better adaptability to component design boundaries and shapes.
Article
Engineering, Biomedical
Arun Arjunan, Suhaib Zahid, Ahmad Baroutaji, John Robinson
Summary: The COVID-19 pandemic has led to global shortages of nasopharyngeal swabs, prompting researchers to develop 3D printed swabs to reduce patient discomfort.
JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Yutai Su, Xin Wu, Jing Shi
Summary: A multimaterial strategy combined with structure innovation is adopted to enhance structural stiffness while retaining the auxetic behavior for auxetic metamaterials. A bimaterial reentrant structure with additional soft arch-like beams and hinges is proposed and investigated using experimental and simulation approaches. The results demonstrate that reducing the strength of the hinge significantly reduces the buckling issue of the beam/wall and minimizes the reduction of auxetic behavior due to increased stiffness. Thus, the strategy to enhance design flexibility for auxetic metamaterials is verified.
MECHANICS OF ADVANCED MATERIALS AND STRUCTURES
(2022)
Article
Multidisciplinary Sciences
Carly Strasser, Eesha Khare
Article
Engineering, Mechanical
Ehsan Hajiesmaili, Eesha Khare, Alex Chortos, Jennifer Lewis, David R. Clarke
EXTREME MECHANICS LETTERS
(2019)
Review
Nanoscience & Nanotechnology
Eesha Khare, Niels Holten-Andersen, Markus J. Buehler
Summary: Transition-metal coordination complexes are being used to engineer the mechanical properties of advanced structural materials, offering dynamic, tunable, and reversible properties. Their application in bioinspired materials design presents opportunities for novel materials with tunable mechanical properties.
NATURE REVIEWS MATERIALS
(2021)
Article
Energy & Fuels
Jocelyn H. Ting, Eesha Khare, Anthony DeBellis, Brian Orr, Jerome S. Jourdan, Francisco J. Martin-Martinez, Kai Jin, Bernie L. Malonson, Markus J. Buehler
Summary: In this study, we found that adding MDI-based additives enhances the phase stability of SBS-modified asphalt, addressing the issue of separation between SBS polymer and asphalt components. Our research also indicates that MDI acts as a compatibilizing agent between asphaltenes and SBS, improving the phase stability of the modified asphalt and reducing its susceptibility to degradation.
Article
Engineering, Biomedical
Chi-Hua Yu, Eesha Khare, Om Prakash Narayan, Rachael Parker, David L. Kaplan, Markus J. Buehler
Summary: Collagen is a crucial structural protein in human tissues, commonly used for repairs and regeneration, but designing specific collagen sequences remains a challenge. Research shows that mutations to glycines, mutations in the middle of a sequence, and short sequence lengths have the greatest impact on the stability of collagen structures.
JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS
(2022)
Article
Multidisciplinary Sciences
Eesha Khare, Chi-Hua Yu, Constancio Gonzalez Obeso, Mario Milazzo, David L. Kaplan, Markus J. Buehler
Summary: A general model using deep learning and genetic algorithm was developed to design collagen sequences with specific melting temperatures (Tm). Experimental and computational methods were used to verify the accuracy of the model in predicting Tm values. The study also identified the most frequently occurring collagen triplets and their correlation with triple-helical quality. This research is critical for the development of collagen sequences with specific Tm values for materials manufacturing and biomedical applications.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Materials Science, Biomaterials
Eesha Khare, Constancio Gonzalez-Obeso, David L. Kaplan, Markus J. Buehler
Summary: This study demonstrates the use of Transformer models to predict the thermal stability of collagen triple helices based on the primary amino acid sequence. The results show that a small Transformer model and a pretrained ProtBERT model have similar performance, with the small model requiring fewer parameters. Additionally, the study suggests the potential of this approach for predicting other biophysical properties.
ACS BIOMATERIALS SCIENCE & ENGINEERING
(2022)
Review
Chemistry, Multidisciplinary
Sabrina C. Shen, Eesha Khare, Nicolas A. Lee, Michael K. Saad, David L. Kaplan, Markus J. Buehler
Summary: Engineered materials are important for modern technology but often contribute to ecological deterioration. Next-generation materials can address sustainability goals by providing alternatives to fossil fuel-based materials and reducing extraction processes and solid waste. Challenges include investigating and designing new feedstocks, which are mechanically weak and difficult to standardize. This review outlines a framework for examining sustainability in material systems and discusses the role of computational tools in discovering novel sustainable materials, with a focus on bioinspired and biobased materials.
Article
Polymer Science
Jake Song, Eesha Khare, Li Rao, Markus J. Buehler, Niels Holten-Andersen
Summary: Rheology experiments and density functional theory calculations were used to characterize the stability of coordination complexes between histamine and imidazole with Ni2+, Cu2+, and Zn2+. It was found that the binding hierarchy is driven by the specific affinity of the metal ions to different coordination states, which can be macroscopically tuned by changing the metal-to-ligand stoichiometry. These findings facilitate the rational selection of metal ions for optimizing the mechanical properties of metal-coordinated materials.
MACROMOLECULAR RAPID COMMUNICATIONS
(2023)
Article
Materials Science, Biomaterials
Eesha Khare, Xiangjun Peng, Zaira Martin-Moldes, Guy M. Genin, David L. Kaplan, Markus J. Buehler
Summary: Model verification is critical for scientific accountability, transparency, and learning. In this study, a model verification approach was applied to a molecular dynamics simulation, successfully replicating the key findings of the original model and gaining new insights. Improvements in model validation processes, particularly through enhanced documentation methods, were discussed. This protocol for model verification can be further applied to validate other simulations.
ACS BIOMATERIALS SCIENCE & ENGINEERING
(2023)
Review
Chemistry, Physical
Marcin Wysokowski, Rachel K. Luu, Sofia Arevalo, Eesha Khare, Witold Stachowiak, Michal Niemczak, Teofil Jesionowski, Markus J. Buehler
Summary: Since the discovery of deep eutectic solvents (DESs) in 2003, significant progress has been made in their preparation and physicochemical characterization. Their low cost and unique tailored properties have led to their increasing importance in sustainable processing and synthesis of advanced materials. This paper discusses the significance of these designer solvents, particularly in the field of biomimetic materials chemistry, and explores their potential for developing biomineralization-inspired hybrid materials.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Physical
Eesha Khare, Jaden Luo, Markus J. Buehler
Summary: Several biological organisms use metal-coordination bonds to create remarkable materials, such as the jaw of the marine worm Nereis virens, which achieves impressive hardness without mineralization. This study investigates the role of metal ions, specifically zinc ions, in the structure and mechanical properties of the Nvjp-1 protein. The initial distribution of metal ions affects the protein's structure, while tensile strength is influenced by hydrogen bond content and uniform distribution of metal ions, providing insights for the development of hardened biomaterials and modeling proteins with significant metal ion content.
Article
Chemistry, Multidisciplinary
Eesha Khare, Darshdeep S. Grewal, Markus J. Buehler
Summary: Dynamic noncovalent interactions play a crucial role in the structure and function of biological proteins and have been explored in bioinspired materials. Metal-coordination bonds offer tunability and can control the properties of synthetic materials. However, understanding the exact contribution of these bonds towards mechanical strength and the effect of geometric arrangements is lacking. In this study, we engineer the cooperative rupture of metal-coordination bonds to enhance the rupture strength of metal-coordinated peptide dimers, and we provide quantitative insights into the cooperativity and intrinsic strength limit of these bonds. This work aims to advance the molecular design principles for metal-coordinated materials.