Article
Materials Science, Multidisciplinary
Dinesh K. K. Patel, Xiaonan Huang, Yichi Luo, Mrunmayi Mungekar, M. Khalid Jawed, Lining Yao, Carmel Majidi
Summary: This study achieves multimodal locomotion of soft robots using highly compact and dynamic bistable soft actuators. These actuators can swiftly transform between two oppositely curved states and generate a force of 0.3 N. The consistency and robustness of the actuator response are experimentally validated. The compact and fast-responding properties of the soft bistable actuator allow it to be used as an artificial muscle for shape-reconfigurable soft robots capable of multiple modes of SMA-powered locomotion.
ADVANCED MATERIALS TECHNOLOGIES
(2023)
Article
Automation & Control Systems
Xiaolong Liu, Hui Liu, Jindong Tan
Summary: This article presents a numerical model for predicting actuation frequencies of SMA actuators, taking into consideration factors such as heat convection methods, bias loads, and Joule heating. Experimental verification demonstrates differences between predicted and measured frequencies, highlighting the impact of different bias loads on actuation frequency accuracy.
IEEE-ASME TRANSACTIONS ON MECHATRONICS
(2021)
Article
Automation & Control Systems
Yu Wan, Keith Cuff, Michael J. Serpe
Summary: The research combines Nitinol shape memory alloy and bistable metal strips to create a swimming actuator with both slow moving and fast snapping capabilities, similar to an octopus's movement in water. The actuator is able to swim in multiple directions, controlled by a wireless module, and can potentially be used for environmental monitoring with an onboard sensor. The device has no mechanical parts, making it a cost-effective alternative to traditional boats.
ADVANCED INTELLIGENT SYSTEMS
(2022)
Article
Engineering, Civil
Junjun Guo, Kang Gao, Xinzhi Dang, Yue Zheng, Hao Liang
Summary: An innovative multi-level shape memory alloy (SMA) cable damper is proposed for bridges in near-fault seismic regions. The study presents a constitutive material model for simulating SMA cables and introduces a seismic fragility analysis framework using Box-Cox transformation and Bayesian inference. The proposed SMA damper reduces damage probabilities of the bridge and careful selection of damper parameters is needed for desired seismic performance.
ENGINEERING STRUCTURES
(2023)
Review
Construction & Building Technology
Chenxi Shao, Yonghui Huang
Summary: This paper introduces the method of reinforcing steel structures using shape memory alloys (SMAs) and the latest research progress, opportunities, and challenges in the field of steel structural reinforcement. The properties of SMAs, the construction forms and working mechanisms of various components are detailed. The application of SMAs in steel structure reinforcement and its effects are analyzed.
Article
Automation & Control Systems
Christopher Bishop, Matteo Russo, Xin Dong, Dragos Axinte
Summary: This article introduces a novel design and motion strategy for underactuated continuum robots (CRs). Shape memory alloy wires are used to control clutches that lock cables for section locking. The proposed design includes beaded cables for improved clutching strength. The prototype demonstrates a mean repeatability of 1.41mm, with section locking achieved in 1 s and section unlocking achieved in 5 s.
IEEE-ASME TRANSACTIONS ON MECHATRONICS
(2022)
Article
Engineering, Electrical & Electronic
Wei Wang, Wenxin Zeng, Aydin Sadeqi, Sameer Sonkusale
Summary: A battery-free solution utilizing shape memory alloy (SMA) to capture interesting temperature events and record temperature history is presented in this study. Experimental validation demonstrates the feasibility of monitoring and recording temperature events at 30 degrees Celsius using SMA, showing practicality and effectiveness of the proposed approach.
IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS
(2021)
Article
Construction & Building Technology
Xiaohong Long, Yongtao Ma, Yu Miao, Bin Ruan
Summary: This study proposes a flexible circumferential joint based on shape memory alloy for seismic mitigation of shield tunnels. The joint is shown to have good energy dissipation and self-recovery effects, and can meet the mechanical performance requirements. It improves the seismic safety of tunnel structures.
TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY
(2023)
Article
Nanoscience & Nanotechnology
Peng Chen, Yunfan Liu, Na Min, Meimei Wang, Xiaorong Cai, Mingjiang Jin, Xuejun Jin
Summary: In this study, an excellent two-way shape memory effect (TWSME) with large magnitude and small cyclic degradation of NiTi wires is achieved by combining martensite deformation and nanocrystallization. The wires exhibit a maximum TWSME strain of 7.37% after being pre-deformed to 11% and maintain a stable strain of 6.88% after 20 cycles. The excellent TWSME is attributed to the dislocation structures induced by martensite deformation and the nanocrystalline strengthened matrix.
SCRIPTA MATERIALIA
(2023)
Article
Engineering, Civil
Xuhong Zhou, Bin Han, Ke Ke, Jin Di, Fengjiang Qin, Long Hu
Summary: This study investigates the mechanical properties of Shape Memory Alloys (SMAs) plates under cyclic tension-compression loading. The findings reveal asymmetric stress-strain curves and different residual strains under varied conditions.
ENGINEERING STRUCTURES
(2023)
Article
Engineering, Electrical & Electronic
Suhel Khan, Yeswanth S. Pydi, S. S. Mani Prabu, I. A. Palani, Pushpendra Singh
Summary: A shape memory alloy (SMA) based aerodynamic composite fin has been developed as an alternative to control the direction of a conventional missile without using a motor. Optimized parameters and adaptive composite actuation were used to achieve maximum displacement and control of the fin.
SENSORS AND ACTUATORS A-PHYSICAL
(2021)
Article
Chemistry, Physical
Yajiao Yang, Christian Leinenbach, Moslem Shahverdi
Summary: In this study, TC-PRISMA was used to simulate the precipitation characteristics of an FeMnSi-based shape memory alloy during one-step and two-step aging processes. The results were validated using transmission electron microscopy (TEM) to examine the microstructures, particularly the VC precipitates. Thermomechanical characterization was conducted to investigate the recovery stress of the FeMnSi-SMA under the different aging conditions. The simulation results showed that two-step aging achieved a similar precipitation state in a significantly shorter time compared to one-step aging, and the recovery stress and fracture strain differed between the two conditions.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Engineering, Civil
Bin Wang, Songye Zhu
Summary: This study conducted a systematic experimental investigation on the cyclic behavior of iron-based shape memory alloys (Fe-SMAs) and evaluated their performance under tension-compression loadings. The results show that Fe-SMAs exhibit satisfactory performance with excellent deformation capability and fatigue behavior, providing a promising solution for developing high-performance seismic devices.
ENGINEERING STRUCTURES
(2022)
Article
Engineering, Electrical & Electronic
Hangyeol Baek, Abdul Manan Khan, Youngshik Kim
Summary: In this research, a simple and innovative bidirectional shape memory alloy (SMA) actuator is presented for use in compliant rotary joints of small bio-inspired robots. The actuator consists of a SMA wire, a rotation axis, and supporting elements. The SMA wire, in a double bend shape, provides forward and backward rotation without the need for additional hardware, such as transmission mechanisms or antagonistic force elements.
SENSORS AND ACTUATORS A-PHYSICAL
(2023)
Article
Nanoscience & Nanotechnology
Maryam Mohri, Irene Ferretto, Christian Leinenbach, Dohyung Kim, Dimitrios G. Lignos, Elyas Ghafoori
Summary: This study systematically investigated the effects of heat and thermomechanical treatments on the pseudo-elastic behavior of an Fe-based shape-memory alloy. The results showed that decreasing the grain size and precipitation of VCs resulted in an improved pseudo-elasticity. The thermomechanical treatment decreased the number of thermal twins and developed a [111] texture in the austenite phase, which reduced the critical stress for inducing martensite.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Energy & Fuels
Nian Li, Renjun Guo, Anna Lena Oechsle, Manuel A. Reus, Suzhe Liang, Lin Song, Kun Wang, Dan Yang, Francesco Allegretti, Ajeet Kumar, Matthias Nuber, Jan Berger, Sigrid Bernstorff, Hristo Iglev, Juergen Hauer, Roland A. Fischer, Johannes V. Barth, Peter Mueller-Buschbaum
Summary: This study investigates the degradation mechanisms of solid-state dye-sensitized solar cells using grazing-incidence small-angle X-ray scattering. The results show that dye aggregation on the TiO2 surface leads to a decrease in device performance, and the decay is faster in small-pore TiO2 electrodes compared to big-pore ones.
Article
Materials Science, Multidisciplinary
Johannes T. Kuechle, Aleksandr Baklanov, Ari P. Seitsonen, Paul T. P. Ryan, Peter Feulner, Prashanth Pendem, Tien-Lin Lee, Matthias Muntwiler, Martin Schwarz, Felix Haag, Johannes Barth, Willi Auwaerter, David A. Duncan, Francesco Allegretti
Summary: This research reveals the presence of a second silicon species, a Si-Ag alloy, between the silicene and the silver substrate, which provides support for the silicene layer. The findings challenge the current understanding of the structural properties of the silicene/Ag(111) interface and may have implications for the stabilization of other 2D materials grown epitaxially on metal surfaces.
Article
Chemistry, Multidisciplinary
Peter Knecht, Dennis Meier, Joachim Reichert, David A. Duncan, Martin Schwarz, Johannes T. Kuechle, Tien-Lin Lee, Peter S. Deimel, Peter Feulner, Francesco Allegretti, Willi Auwaerter, Guillaume Medard, Ari Paavo Seitsonen, Johannes Barth, Anthoula C. Papageorgiou
Summary: Ru-porphyrins serve as pedestals for the assembly of N-heterocyclic carbenes (NHCs) on solid surfaces. A phenomenon of transferring Ru-porphyrin molecules from the surface to the next layer can be observed upon deposition of a simple NHC ligand on a close-packed Ru-porphyrin monolayer. The uptake of NHC induces a rearrangement of the molecular layer, which can be reversed by thermal desorption of the NHC ligand. Understanding such mass transport processes is crucial for surface functionalization with carbenes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Arash Badami-Behjat, Peter S. Deimel, Francesco Allegretti, Eva Ringel, Kingsuk Mahata, Michael Schmittel, Johannes V. Barth, Wolfgang M. Heckl, Markus Lackinger
Summary: The self-assembly of supramolecular monolayers at liquid-solid interfaces is a well-established research field. In this study, a passivated Au(111) surface with a monolayer of iodine atoms was used to explore the effects of the underlying surface on interfacial monolayers. The experiments revealed that molecule-surface interactions can cause substrate-induced polymorphism and significantly affect the thermodynamic stability of supramolecular monolayers. This study highlights the crucial and specific thermodynamic influence of the underlying surface on monolayer formation.
CHEMISTRY OF MATERIALS
(2022)
Article
Chemistry, Physical
Salih Demirci, Taylan Gorkan, Safak Callioglu, V. Ongun Ozcelik, Johannes Barth, Ethem Aktuerk, Salim Ciraci
Summary: A hydrogenated carbon monolayer exhibits various functionalities and can be used in composite structures with topological properties. It has applications in energy storage and optoelectronics, and the commensurability of different materials ensures the effectiveness of these functionalities.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Engineering, Mechanical
Kiran Jacob, Aditya Suryadi Tan, Thomas Sattel, Manfred Kohl
Summary: A hybrid damper concept combining magnetorheological fluid (MRF) and shape memory alloy (SMA) has been proposed. The performance of different MRF-SMA configurations has been investigated, demonstrating the complementarity of operation between MRF and SMA dampers, resulting in improved damping performance and reduced energy consumption.
Article
Chemistry, Multidisciplinary
Paul Leidinger, Mirco Panighel, Virginia Perez Dieste, Ignacio J. Villar-Garcia, Pablo Vezzoni, Felix Haag, Johannes V. Barth, Francesco Allegretti, Sebastian Guenther, Laerte L. Patera
Summary: Dynamic covalent chemistry is used for designing covalent organic frameworks with high crystallinity achieved through reversible bond formation. In this study, near-ambient pressure X-ray photoelectron spectroscopy is employed to investigate the reversible formation of a two-dimensional boroxine framework. By mapping the pressure-temperature parameter space, the regions where the rates of condensation and hydrolysis reactions dominate are identified, which enable the thermodynamically controlled growth of crystalline frameworks.
Article
Chemistry, Multidisciplinary
Federico Frezza, Frederik Schiller, Ales Cahlik, Jose Enrique Ortega, Johannes V. Barth, Andres Arnau, Maria Blanco-Rey, Pavel Jelinek, Martina Corso, Ignacio Piquero-Zulaica
Summary: In this study, quinoidal ligands were reacted with single cobalt atoms on an Au(788) surface in ultra-high vacuum, resulting in the formation of cobalt-quinoid chains. The electronic structure of these chains was investigated using angle-resolved photoemission spectroscopy, and their narrow bandgap structure was revealed using low-temperature scanning tunneling microscopy/spectroscopy. Theoretical calculations confirmed that the observed electronic bands originated from the efficient hybridization of cobalt and molecular orbitals. This work provides a foundation for the systematic search of similar one-dimensional π-d hybridized metal-organic chains with tunable electronic and magnetic properties.
Article
Engineering, Mechanical
Emil R. Mamleyev, Chun Him Lee, Jan G. Korvink, Manfred Kohl, Kirill V. Poletkin
Summary: This paper presents the results of a comprehensive study on the pull-in phenomenon in a hybrid levitation microactuator. Square-shaped proof masses of different sizes were electromagnetically levitated and their pull-in actuation was measured. The study found that the pull-in actuation is nonlinearly dependent on the size, mass, and levitation height of the proof masses. Extensive simulation and direct comparison with experimental results showed a good agreement between theory and experiments.
Article
Chemistry, Multidisciplinary
Joel Joseph, Erika Fontana, Thibaut Devillers, Nora M. Dempsey, Manfred Kohl
Summary: Thermomagnetic generation is a promising technology for converting low-grade waste heat into electricity. The development of efficient thermomagnetic generators requires tailored thermomagnetic materials and innovative designs for fast heat transfer. This study reports on the performance of a Gadolinium (Gd)-film-based thermomagnetic generator optimized for resonant self-actuation near room temperature, which exhibits high oscillation frequencies and large strokes, resulting in efficient conversion of thermal energy into electrical energy.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Biao Yang, Kaifeng Niu, Nan Cao, Nitika Grover, Wenchao Zhao, Alexander Riss, Jonas Bjoerk, Willi Auwaerter, Johannes V. Barth, Mathias O. Senge
Summary: In this study, the behavior of 1,3-disubstituted BCP moieties on metal surfaces was examined using low-temperature scanning tunneling microscopy/non-contact atomic force microscopy studies and density functional theory modeling. The configuration, supramolecular assembly, and thermally activated dehalogenative coupling reactions of BCP-containing precursors on Au(111) were investigated, resulting in the formation of polymeric chains. These findings provide sub-molecular insights into the behavior of BCP scaffolds on surfaces and expand the potential application of BCP derivatives in custom-designed surface architectures.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Taylan Gorkan, Salih Demirci, Johannes V. Barth, Ethem Aktuerk, Salim Ciraci
Summary: Based on first-principles calculations, it is predicted that the 2H-MoS2 monolayer can also exist in a stable biphenylene network phase (B-MoS2). B-MoS2 has a narrow band gap, directional electronic conduction, and strong absorption in the near-infrared region. It can form multilayers and a metallic 3D layered crystal, and its band gap can be modulated under applied strains.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Multidisciplinary Sciences
Nan Cao, Biao Yang, Alexander Riss, Johanna Rosen, Jonas Bjork, Johannes V. Barth
Summary: Enetriynes, a distinct class of highly conjugated pi-system compounds, are formed with high selectivity by tetramerization of terminal alkynes on Ag(100) surface. The formation is induced by O-2 exposure, resulting in deprotonation of terminal alkyne moieties and the evolution of organometallic bis-acetylide dimer arrays. Subsequent thermal annealing leads to the generation of tetrameric enetriyne-bridged compounds, which readily self-assemble into regular networks. High-resolution scanning probe microscopy, X-ray photoelectron spectroscopy, and density functional theory calculations are employed to examine the structural features, bonding characteristics, and reaction mechanism.
NATURE COMMUNICATIONS
(2023)
Article
Engineering, Mechanical
Gowtham Arivanandhan, Zixiong Li, Sabrina M. Curtis, Lisa Hanke, Eckhard Quandt, Manfred Kohl
Summary: We propose a novel design approach to optimize the power consumption of cantilever-based shape memory alloy (SMA)/Si bimorph microactuators. By utilizing finite element simulation, additional folded beams are designed in the perpendicular direction to homogenize the temperature distribution along the cantilevers. The temperature-homogenized SMA/Si microactuators exhibit a significant reduction in power consumption compared to the conventional double-beam cantilever design, up to 48%.
Article
Chemistry, Multidisciplinary
Nan Cao, Jonas Bjoerk, Eduardo Corral-Rascon, Zhi Chen, Mario Ruben, Mathias O. Senge, Johannes V. Barth, Alexander Riss
Summary: This study investigates how aromaticity affects the reactivity of alkyne-substituted porphyrin molecules on a Au(111) surface. The experiments show that carbon atoms stabilized by aromaticity display lower reactivity, which is consistent with density functional theory calculations.
