High Bending Research Articles

Stiff yet Bendy: Tubular Transmissions for Driving Surgical Robots through Flexible Endoscopes

Concentric push–pull robots delivered through flexible endoscopes work best if their laser-cut transmission tubes have high axial stiffness, high torsional stiffness and low bending stiffness. This paper simultaneously addresses all three output stiffness values in the transmission design problem, explicitly considering axial stiffness, whereas prior work on laser-cut tube design has focused on the bending/torsional stiffness ratio. We demonstrate an inherent trade-off present in existing laser-cut patterns: it is difficult to simultaneously achieve high axial stiffness and low bending stiffness because these properties are very tightly correlated. To break this correlation and design all three stiffness independently, we propose a new type of laser material removal pattern that leverages local stiffness asymmetry (EI[Formula: see text] [Formula: see text] EI[Formula: see text]) in discrete bending segments separated by segments of solid tube. These discrete asymmetric segments are then rifled down the tube to achieve global stiffness symmetry. We parameterize the design and provide a study of the properties through finite-element analysis. We also consider the effect of interference between the tubes when the discrete segments are not aligned. Results show that our discrete asymmetric segment concept can achieve high axial stiffness and torsional stiffness better than previously suggested laser patterns while maintaining equally low bending stiffness. We also experimentally validated the proposed design’s properties and actuation performance with professionally manufactured prototype Nitinol tubes for use in an endoscopic robot system.

Machine Learning-Based Flexural Strength Prediction of Layered Ceramic Materials

The flexural strength of layered ceramic materials plays an important role in its application, and are affected by many structural parameters and process factors. At present, the experimental methods of layered ceramic materials are inefficient, and it is impossible to systematically analyze the effect of structural parameters and process factors on the bending strength of silicon nitride ceramics. In this paper, a machine learning model based on 3 classical algorithms is successfully established, and its bending strength is predicted with 5 indexes. According to the SHAP diagram, the material of layered ceramics has the greatest influence on the bending strength, followed by the sintering temperature, this article provides the basis and reference for the preparation of layered ceramic materials with high bending strength.

Quantitative Characterization of Channel Morphology and Main Controlling Factor of Shallow Water Delta—A Case from Ganjiang Delta, Jiangxi, China

(1) This paper selects the modern delta formed by the Ganjiang tributary in Poyang Lake. By performing high density statistical analysis of distribution channel parameters in the area using satellite images and geographic information processing software (LucaSpaceViewer 4.5.2, ArcGIS Pro 3.0.2, Global Mapper v23.1), including length, width, bifurcation angle, bifurcation frequency, and channel sinuosity, the distribution characteristics of delta distribution channels are derived and quantitatively characterized. (2) Classification and evaluation of these characteristics are carried out using factor and cluster analysis, ultimately identifying controlling factors affecting the morphology and distribution of the distribution channels. By statistically analyzing the geometric and bifurcation data of the channels, factor and cluster analysis for data reduction and classification, the channel is finally divided into three categories: Type I channels have relatively high channel length, width, sinuosity, bending amplitude, and a lower bifurcation (or confluence) growth rate; Type II channels are characterized by low channel length, moderate channel width, low sinuosity, low bending amplitude, and a high bifurcation (or confluence) growth rate; Type III channels are defined by moderate channel length, low width, high sinuosity, high bending amplitude, and low bifurcation (or confluence) frequency. (3) After excluding the influence of other factors, it was found that the main controlling factor for the morphology of the Ganjiang Delta channel is flow velocity, which is influenced by changes in the terrain slope. Flow velocity directly affects channel sinuosity, bending amplitude, and bifurcation (or confluence) frequency, and indirectly affects channel length and width.

A strain rate-dependent distortional hardening model for nonlinear strain paths

In this paper, a strain rate-dependent distortional hardening model is firstly proposed to describe strain rate-dependent material behaviors under linear and nonlinear strain paths changes in 0≤θpathchange≤180∘. The proposed model is formulated based on the simplified strain rate-independent distortional hardening model (Choi and Yoon, 2023). Any yield function could be used for the strain rate-dependent isotropic and anisotropic yielding. For the linear strain path, the strain rate-dependent isotropic hardening behavior could be explained by two state variables representing rate-dependent yielding and convergence rate of flow stress under monotonically increasing loading condition, respectively. For the nonlinear strain paths, the strain rate-dependent material behaviors such as Bauschinger effect, yield surface contraction, permanent softening, and nonlinear transient behavior could be described by modifying the evolution equations of the simplified strain rate-independent distortional hardening model with a logarithmic term of strain rate. For the verification purpose, it was used the strain-rate dependent tension-compression experiments of TRIP980 and TWIP980 (Joo et al., 2019). In addition, a high speed U-draw bending test was conducted with original and pre-strained specimens. The springback prediction in high speed U-draw bending test was performed by using strain rate-independent isotropic, strain rate-dependent isotropic-kinematic and distortional hardening models. It is identified that the proposed model showed the most accurate prediction for the pre-strained specimen where the possible bilinear and trilinear path change in 0≤θpathchange≤180∘ is observed while it showed the same accuracy for the original specimen where main strain path change occur in forward-reverse manner (θpathchange=180∘).

Noninvasive high-resolution deep-brain photoacoustic imaging with a negatively focused fiber-laser ultrasound transducer

Noninvasive high-resolution deep-brain imaging is essential to fundamental cognitive process study and neuroprotective drugs development. Although optical microscopes can resolve fine biological structures with good contrast without exposure to ionizing radiation or a strong magnetic field, the optical scattering limits the penetration depth and hinders its capability for deep-brain imaging. Here, in vivo high-resolution imaging of the whole mouse brain is demonstrated by using a photoacoustic computed tomography system with a negatively focused fiber-laser ultrasound transducer. By leveraging the high flexibility and low bending loss of the optical fiber, a rationally designed negatively focused fiber laser cavity exhibits a low detection limit down to 5.4 Pa and a broad view angle of ∼120 deg, enabling mouse brain imaging with a penetration larger than 7 mm and a nearly isotropic spatial resolution of ∼130 μm. In addition, the negative curvature of the fiber laser reduces the working distance, which facilitates the development of a compact and portable linear scanning imaging system. In vivo imaging of a mouse model with intracerebral hemorrhage is also showcased to demonstrate its capability for potential biomedical and clinical applications. With high spatial resolution and large tissue penetration, the system may provide a noninvasive, user-friendly, and high-performance imaging solution for biomedical research and preclinical/clinical diagnosis.

New High Efficiency and Strength Bending Strain Sensor Based on Piezoelectric Stacks

New High Efficiency and Strength Bending Strain Sensor Based on Piezoelectric Stacks

Computational modeling of vascular tissue damage for the development of safe interventional devices

During intravascular procedures, medical devices interact mechanically with vascular tissue. The device design faces a trade-off: although a high bending stiffness improves its maneuvrability and deliverability, it may also trigger excessive supra-physiological loading that may result in tissue damage. In particular, the collagen fibers in vascular walls are load-bearing but may rupture on a microscopic scale due to mechanical interaction. When the mechanical load increases even further, tissue rupture or puncture occurs. To mitigate tissue damage, the current work focusses on the development of computational Finite Element (FE) based models wherein state-of-the-art constitutive tissue models are applied toward the design of safe devices. Several experiments are presented for tissue characterization in which device-mimicking indenters are pressed onto a porcine tissue. In these experiments, the Mullins effect, which is related to tissue damage, is observed. Consequently, the mechanical behavior of tissue, including the evolution of damage-induced energy dissipation, is accurately described by adopting a hyperelastic model incorporating the damage approach by Weisbecker et al. (2012). From the experimentally validated computational model, a novel design criterion is established, which allows for safe device development. Furthermore, an energy density criterion for the onset of puncture is proposed. With these tools, several frequently used work-horse guidewires are numerically evaluated.

Influence of Cutting Surface Condition and Composition on High-Temperature Oxidation Behavior of Ti2 Al C MAX Phase Ceramics

Ti2AlC, one of the MAX phase ceramics, has metal-like properties (electrical conductivity, high fracture toughness and good machinability) and ceramic-like properties (low density, high-temperature oxidation resistance and high bending strength). Ti2AlC ceramics can be cut with cemented carbide tools and the mechanical strength does not decrease significantly after cutting. Ti2AlC ceramics have potential as high-strength machinable ceramics for use in high temperature components. However, the oxidation resistance of Ti2AlC ceramics decreases after cutting because the cutting damages inhibit the formation of protective Al2O3 scale. There are few discussions on the effect of cutting surface conditions on oxidation resistance of Ti2AlC ceramics. The continued growth of the protective Al2O3 scale requires a sufficient Al supply during high-temperature oxidation. The oxidation resistance of Ti2AlC ceramics is reduced when a non-protective TiO2 scale forms on the surface. As one of the common methods to prevent the growth of the TiO2 scale is Nb addition in Ti-based alloys and compounds. The oxidation resistance of as-machined Ti2AlC ceramics may be improved by increasing the amount of Al and Nb additions. This study reports the influences of cutting surface conditions and composition on oxidation behavior of Ti2AlC ceramics. Commercial Ti, Al, C and Nb powders were mixed in Ti:Al:C:Nb molar ratios of 2:1.2:0.9:0 and 1.9:1.2:0.9:0.1 with the corresponding samples receiving the designations Al1 and Al1.2Nb. The powder mixture was annealed for 12 h in a vacuum at 1300°C. The synthesized powder was consolidated over 15 min using a pulsed electric current sintering technique at 1300°C, in a vacuum, and under a uniaxial pressure of 30 MPa. The phases present in the sintered samples were also identified by XRD. Milling tests were performed on a 4 x 4 mm sample surface using a 2 mm diameter end-mill mounted on a plane milling machine. Dry cutting was performed with a spindle speed, feed rate, and cut depth of 4000 rpm, 46 mm/min, and 100 μm. Threading tests were cut into an JIS-M6 bolt shape with a thickness of 3 mm with a lathe and diamond saw. The surface roughness of each sample was measured using a surface texture measuring instrument. The samples were heated in an electric furnace at 1200°C for 4 h in laboratory air. The surface and cross-sections of the oxidized samples were observed via scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX).The main peaks of all sintered samples in these XRD patterns were identified as originating from Ti2AlC and minor peaks originating from TiAl3 (Al-rich phase). The average arithmetic mean roughness (R a) values of the end-milled and threaded surfaces were 0.8 and 4.5 μm. The SEM and EDX results show that a continuous Al2O3 scale formed on the end-milled surface of Al1.2 and Al1.2Nb after the oxidation test. The results of SEM and EDX investigations indicate that a non-protective TiO2 scale had formed on the threaded surface of Al1 and a continuous Al2O3 scale with a thickness of less than 4 μm was formed on the threaded surface of Al1.2Nb after the oxidation test. The Al-rich phase provided the Al necessary for the formation of a continuous Al2O3 scale on the end-milled surface. The oxidation resistance of Ti2AlC ceramics was greatly reduced in the case of screw-like shapes with high R a values and many corners on the cutting surface. The addition of Nb improves the oxidation resistance of Ti2AlC ceramics under such cutting surface conditions. The cause of non-protective oxidation was the destruction of the Al2O3 scale because of the growth of TiO2 scale. The TiO2 scale tends to form at corners where continuous Al2O3 scale formation is difficult. One of the factors that improves the oxidation resistance of Ti2AlC ceramics with screw shapes is the suppression of TiO2 growth by Nb addition. The higher Al concentration and the addition of Nb remarkably increase the oxidation resistance of the Ti2AlC ceramics after cutting.

Polylactide Composites Reinforced with Pre-Impregnated Natural Fibre and Continuous Cellulose Yarns for 3D Printing Applications.

Achieving high-performance 3D printing composite filaments requires addressing challenges related to fibre wetting and uniform fibre/polymer distribution. This study evaluates the effectiveness of solution (solvent-based) and emulsion (water-based) impregnation techniques to enhance fibre wetting in bleached flax yarns by polylactide (PLA). For the first time, continuous viscose yarn composites were also produced using both impregnation techniques. All the composites were carefully characterised throughout each stage of production. Initially, single yarns were impregnated and consolidated to optimise formulations and processing parameters. Solution impregnation resulted in the highest tensile strength (356 MPa) for PLA/bleached flax filaments, while emulsion impregnation yielded the highest tensile strength for PLA/viscose filaments (255 MPa) due to better fibre wetting and fibre distribution. Impregnated single yarns were then combined, with additional polymer added to produce filaments compatible with standard material extrusion 3D printers. Despite a reduction in the mechanical performance of the 3D-printed composites due to additional polymer impregnation, relatively high tensile and bending strengths were achieved, and the Charpy impact strength (>127 kJ/m2) for the viscose-based composite exceeded the reported values for bio-derived fibre reinforced composites. The robust mechanical performance of these filaments offers new opportunities for the large-scale additive manufacturing of structural components from bio-derived and renewable resources.

Method to improve the bonding strength of polyethylene terephthalate core with glass fiber reinforced skins in a sandwich composite

AbstractComposite materials provide an alternative to conventional structural materials. Sandwich composites show high bending strength and superior strength‐to‐weight ratio. The major drawback in sandwich composites is debonding of skin from core, that causes failure of a component during the usage at different loads. To overcome this issue, the current work identifies a solution of introducing nylon screws (M6 × 32) to adhere firmly the skins consisting of glass fibers with PET (Polyethylene Terephthalate) core. The sandwich composites were fabricated by vacuum infusion process. Two flat sandwich composites were fabricated; one with nylon screws placed perpendicular to the skin and the other a plain sandwich composite. Mechanical characteristics of the specimens such as fracture toughness, flexural strength and shear strength were studied. Specimens with nylon screws showed 21.78% more fracture toughness compared to plain specimen. The presence of screws acts as hindrance to the propagation of cracks in the interfacial region resulting in the enhancement of debonding resistance of the specimens. Also, sandwich specimens with nylon screws exhibited 136% and 142% improvement in flexural and shear strength respectively when compared to plain sandwich specimens. The investigation of scanning electron microscope (SEM) images of tested specimens indicates strong interfacial bonding between skin and the core of specimens with nylon screws.Highlights Introduction of light‐weight nylon screws in z‐direction enhanced the bonding between face sheets and foam core. Sandwich composites with nylon screws exhibited superior bending and shear strength compared to plain specimens. Crack propagation in the interfacial region is restricted by the presence of nylon screws. Investigation of fractured specimens indicated a strong interfacial bonding in the specimens with screws.

Experimental and Numerical Indentation Tests to Study the Crack Growth Properties Caused by Various Indenters Under High Temperature

ABSTRACTThis paper investigates the influence of indenter shape and rock texture on the crack growth properties and rock hardness. For this purpose, two different rock specimens such as basalt and marble with various textures were prepared and tested by Vickers indentation hardness device with rhombus indenter shape under two different temperatures of 35°C and 100°C. Concurrent with the experimental test, Vickers indentation simulations have been done on three calibrated rock models with nine different indenter shapes. The tensile strength of marble was 8 MPa, while basalt had a tensile strength of 10.8 MPa. Regarding compressive strength, marble exhibited 71 MPa, whereas basalt had a compressive strength of 153 MPa. Marble and basalt had elastic moduli of 45 and 95 GPa, respectively. The physical loading was applied vertically at a rate of 0.004 mm/min. The rock's texture and temperature significantly impact Vickers indentation hardness. Penetration by the Vickers indenter creates an elastic‐plastic stress field, leading to radial cracks due to exceeding the critical stress level. Ring cracks are caused by bulging of the test material and nested cracks directly under the indentation due to high shear and bending stresses in the region. The indentation shape affected the extent of the damage zone below it, leading to increased crack growth with smaller indentation diameters. The radial fracture number increased when the cross‐section changed from circular to quadrilateral shape. The crack growth and damage zone area increased with higher rock temperature due to increased rock brittleness.

Bioinspired Soft Actuators for High Bending Stiffness and Flexible Spatial Locomotion

Bioinspired Soft Actuators for High Bending Stiffness and Flexible Spatial Locomotion

Flexible Hair‐Like Piezoelectric Acoustic Particle Velocity Sensor with Enhanced Sensitivity for Speaker Recognition

AbstractFlexible resonant acoustic sensors exhibit enhanced sensitivity near their resonant frequencies and have attracted increasing interest as essential components for next‐generation human‐machine speech interactions. However, membrane‐based resonant acoustic sensors are bulky owing to the inherently high bending stiffness of the sensing membrane. Inspired by the tiny hair‐based sensitive acoustic receptors of spiders, this study reports a hair‐like piezoelectric resonant acoustic particle velocity sensor (HP‐APVS) that enables highly sensitive sound sensing with a significantly reduced size. The HP‐APVS device is essentially a polyimide cantilever array fabricated using Nb0.02‐Pb(Zr0.6Ti0.4)O3 (PZT) on polyimide and self‐bending processes. The experimental results demonstrate that the HP‐APVS shows a linear response to acoustic particle velocity instead of acoustic pressure, with enhanced sensitivity in the resonance mode. Additionally, the proposed HP‐APVS exhibits an outstanding speaker recognition rate of 95.3% with an error rate reduction of 75% compared with that of a reference commercial microphone, indicating many potential applications in the realms of biometric authentication, voice user interfaces, and other intelligent acoustic electronics.

Effects of Core and Surface Materials on the Flexural Behavior of Lightweight Composites Sandwich Beams

Sandwich composite elements are used in many sectors thanks to their low weight/strength ratios, high bending strength, good thermal insulation properties, and low costs. It is widely used in the machinery and construction industry, especially in land, sea, and air vehicles. The main objective of this research is to design and produce lightweight, durable, insulated, and low-cost, sustainable building elements that will meet emergency shelter needs after disasters. For housing purposes, 24 sandwich beams were prepared, eight designs with different surface coatings and core materials, and three in each design group. The effects of surface coating and core material on behavior were investigated with four-point bending experiments. Load-displacement relationships were determined from the experiments, and the beams' load-carrying capacities and failure patterns under the effects of bending and shearing were determined. In addition, theoretical methods determined maximum load values and compared them with the results of the experiments. As a result of the experiments, it was concluded that the best-performing design under bending effects was sandwich beams with plywood surface and XPS core.

Highly Deformable and Robust Ionic Structure for Multi‐Tissue Adaptive Hemostatic Sponges

AbstractAccidental trauma is always accompanied by tissue defects with noncompressible hemorrhages. Deformable and tough biomaterials are desirable for self‐compressible hemostasis, although their preparation is challenging. Here, a critical‐size calcium phosphate (C–CaP) with polymer‐like high deformability and mineral‐like high bending strength is prepared, which is hybridized with silk fibroin (SF) to fabricate a hemostatic sponge (SF‐C). C–CaP endows SF‐C with an ultrahigh elastic modulus (36.0 kPa) among analogous materials, leading to an ultrafast water absorption rate (1.2 g cm−3 s−1) and space‐filling rate (200.0%/s). The deformability of the SF‐C sponge further enables self‐adaptability to defects with micrometre‐scale precision. Consequently, SF‐C achieves rapid hemostasis in both damaged soft tissues and hard tissues in rats, resulting in less blood loss and a shorter hemostatic time than those of clinical materials. This study provides a promising hemostatic material for the treatment of hemorrhages in defective tissues and expands the current knowledge by revealing the critical‐sized ionic structure and unique mechanics of C–CaP.

Prediction of flanking sound transmission through cross-laminated timber junctions with resilient interlayers

While the low weight and high bending stiffness of cross-laminated timber (CLT) are key to its popularity, these properties also contribute to poor acoustic performance. Notably flanking sound transmission is a critical factor, driving the need for vibration reduction solutions such as resilient interlayers in the junction design. However, due to the complex material behavior of CLT and resilient interlayers, the improvement related to these solutions is difficult to predict. In this research, an analytical model with low computational cost is developed to evaluate the vibration reduction index Kij for CLT junctions with resilient interlayers. The CLT panels are considered as thin orthotropic plates with homogenized material properties. Three potential material models are proposed for the interlayer: it is considered as a thin plate, a thick flexible layer with out-of-plane motion governed by shear or distributed springs. The prediction model is experimentally validated for junctions consisting of CLT panels, with and without resilient interlayers. For junctions without interlayers, the predicted and experimentally determined vibration reduction index Kij correspond most closely when the junction is realized with stiff connectors. In this case, the predictions are moderately accurate with deviations below 5 dB in 1/3 octave bands up to approximately 2000 Hz for both corner and coplanar transmission paths. For junctions with resilient interlayers, the shear interlayer model exhibits the best performance with deviations of less than 5 dB in most 1/3 octave bands. For frequencies below 1000 Hz, the accuracy of the simplified spring model is comparable to that of the thick layer model. Simulations with equivalent isotropic material parameters yield slightly inferior predictions than for orthotropic parameters if the degree of orthotropy of the panels is high.

Fe‐Mediated Tweaking of Band Bending and Activation Energy in α‐MoO3 Nano Lamella for Enhanced NO2 Gas Detection Under Low Operating Temperature

AbstractConcern over increasing pollution and ways to mitigate it is in high demand due to the swift advancement of technology and the creation of advanced utilities. Nitrogen oxide (NO2) is a well‐known evolved toxin that poses a threat to human health, the environment, and biodiversity. Therefore, several works are carried to sense the NO2 gas at its trace concentration. However, the majority of NO2 sensors that have been reported have inadequate Limit of Detection (LOD), high operating temperature, and low sensitivity. Orthorhombic molybdenum oxide (α‐MoO3) recently emerged as hotspot in the gas sensing research and noted for its high sensitivity, and distinct sensing capabilities owing to its unique layered structure. In this study, Fe‐doped α‐MoO3 nanosheets for NO2 sensing is prepared, and at a low operating temperature of 110 °C, an excellent sensitivity of 1282% for 10 ppm of NO2 is achieved. Long‐term stability, good repeatability, and an ultra‐low detection limit of 79 ppt are also demonstrated by the manufactured sensors. In addition, the obtained low activation energy of ‐2.9 KJ mol−1 and the high band bending for FM6 supports the highly responsive NO2 detection at low operating temperatures.

Simultaneous detection of vector bending and temperature using dual-core fiber cascaded FBG structure

In the paper, we experimentally presented vector bending sensor based on the multimode-dual core- multimode fiber cascaded Fiber Bragg grating (FBG) structure, which owns the ability of dual-parameter detection. These two multimode fibers (MMFs) function as a mode beam expander and a mode coupler, separately, and the FBG is used to eliminate the temperature crosstalk. Because of the central symmetry of the dual-core fiber (DCF) and its two cores arranged in a linear array, the sensor can achieve recognition directional bending. The experiment of results demonstrates our sensor exhibits a robust response to vector bending response with the max bending sensitivities of 18.259 nm/m−1 in the bending direction of 0°. The temperature sensitivity of the resonance wavelength generated by the Mach-Zehnder interferometer (MZI) and FBG can reach −0.285 nm/°C and 0.010 nm/°C, separately. Through the dual wavelength matrix method, we can achieve simultaneous measurement of vector bending response and temperature response. Featuring notable strengths such as high vector bending sensitivity, ease of fabrication, low cost, and direction recognition, the sensor can be applied in various fields of vector bending measurement.

Development of a novel circular saw blade substrate with high stiffness for mitigating vibration noise and improving sawing performance

The circular saw blade substrates featuring a large diameter-thickness ratio and multiple saw teeth are increasingly required to accomplish the first or second machining tasks with high efficiency in sawing operations. However, the weak bending stiffness of this substrate can easily cause intense vibrations and harsh noises, while its special structure characteristics pose further challenges to vibration mitigation. This research develops a novel circular saw blade substrate with high bending stiffness to improve dynamic stability. Taking the geometric features and boundary conditions of the substrate into account, a transverse vibration differential equation for high-speed sawing operation is established to investigate the relationship between the mode shapes of the substrate and the stability performance of the sawing system. Theoretical analysis shows that the laminated structure can enhance the bending stiffness. Using this finding, the novel substrate is designed equipped with an m-shaped damping cavity and a laminated core structure, and its dynamic performance is quantified by the complex modulus law and thin-plate vibration theory. Then, the optimized design of the relevant materials and geometrical dimensions of the novel substrate is executed by the pseudo-density method. Finally, the novel substrate is fabricated and then certified by sawtooth point dynamics tests and sawing experiments. The experimental results show that the sawing quality of the novel substrate is improved by more than 50.2 %, and the sawing vibration and weighted sound pressure level are reduced by about 35 % and 12 dB(A), respectively, compared with the conventional one.

Silk Fibroin Film Decorated with Ultralow FeCo Content by Sputtering Deposition Results in a Flexible and Robust Biomaterial for Magnetic Actuation.

Magnetically responsive soft biomaterials are at the forefront of bioengineering and biorobotics. We have created a magnetic hybrid material by coupling silk fibroin─i.e., a natural biopolymer with an optimal combination of biocompatibility and mechanical robustness─with the FeCo alloy, the ferromagnetic material with the highest saturation magnetization. The material is in the form of a 6 μm-thick silk fibroin film, coated with a FeCo layer (nominal thickness: 10 nm) grown by magnetron sputtering deposition. The sputtering deposition technique is versatile and eco-friendly and proves effective for growing the magnetic layer on the biopolymer substrate, also allowing one to select the area to be decorated. The hybrid material is biocompatible, lightweight, flexible, robust, and water-resistant. Electrical, structural, mechanical, and magnetic characterization of the material, both as-prepared and after being soaked in water, have provided information on the adhesion between the silk fibroin substrate and the FeCo layer and on the state of internal mechanical stresses. The hybrid film exhibits a high magnetic bending response under a magnetic field gradient, thanks to an ultralow fraction of the FeCo component (less than 0.1 vol %, i.e., well below 1 wt %). This reduces the risk of adverse health effects and makes the material suitable for bioactuation applications.