Concave Bending Research Articles

Elasmoid fish scales as a natural fibre composite: microscopic heterogeneities in structure, mineral distribution, and mechanical properties.

The elasmoid scales in teleost fish serve as exemplary models for natural fibre composites with integrated flexibility and protection. Yet, limited research has been focused on the potential structural, chemical, and mechanical heterogeneity within individual scales. This study presents systematic characterizations of the elasmoid scales from black drum fish (Pogonias cromis) at different zones within individual scales as a natural fibre composite, focusing on the microscopic structural heterogeneities and corresponding mechanical effects. The focus field at the centre of the scales exhibits a classical tri-layered collagen-based composite design, consisting of the mineralized outermost limiting layer, external elasmodine layer in the middle, and the unmineralized internal elasmodine layer. In comparison, the rostral field at the anterior end of the scales exhibits a two-layered design: the mineralized outermost limiting layer exhibits radii sections on the outer surface, and the inner elasmodine layer consists of collagen fibre-based sublayers with alternating mineralization levels. Chemical and nanoindentation analysis suggests a close correlation between the mineralization levels and the local nanomechanical properties. Comparative finite element modelling shows that the rostral-field scales achieve increased flexibility under both concave and convex bending. Moreover, the evolving geometries of isolated Mandle's corpuscles in the internal elasmodine layer, transitioning from irregular shapes to faceted octahedrons, suggest the mechanisms of mineral growth and space-filling to thicken the mineralized layers in scales during growth, which enhances the bonding strength between the adjacent collagen fibre layers. This work offers new insights into the structural variations in individual elasmoid scales, providing strategies for bioinspired fibre composite designs with local-adapted functional requirements.

Concave and convex small radius bending behavior of single and multiple layers reinforcement fabrics

Multilayer reinforcement fabrics are increasingly used for manufacturing structural polymer composites. In liquid molding processes, dry reinforcement fabrics are draped on a mold first, and infused with a liquid resin such as an epoxy in a subsequent manufacturing step. This presents major advantages in terms of operational flexibility and costs. However, draping multilayer reinforcement fabrics on complex mold geometries is challenging. Small radius mold corners constitute a major manufacturing challenge as they lead to variability in dry fabric positioning and resin-rich corners in polymer composite parts. Spring-back of fabrics bent over or into single curvature mold corners is a widespread industrial concern. However, contrary to draping over double-curvature surfaces, bending spring-back from convex or concave single-curvature corners has received very limited attention. No testing method is available. This paper quantifies reinforcement fabric bending spring-back. Single and multiple layer stacks were bent along three directions over convex and into concave 90° corners with five radii spanning 1.59 mm to 12.70 mm. In all cases, five replicated tests enabled variability quantification. Fabric stacks were also quantified using cantilevered bending tests for comparison purposes. Mold radius was found to affect the behavior to a larger extent than testing direction, number of layers or use of a binder.

Ultrathin Encapsulation Strategies with Predefined Gate Dielectric Surface Area for Flexible Crystalline Silicon Nanomembrane-Based MOS Capacitors

Ultrathin encapsulation strategies show huge potential in wearable and implantable electronics. However, insightful efforts are still needed to improve the electrical and mechanical characteristics of encapsulated devices. This work introduces Al2O3/alucone nanolaminates using hybrid atomic/molecular layer deposition for ultrathin encapsulation structures employed in crystalline silicon nanomembrane (Si NM)-based metal-oxide-semiconductor capacitors (MOSCAPs). The comprehensive electrical and mechanical analysis focused on the encapsulated and bare MOSCAPs with three gate dielectric diameters (Ø) under planar and bending conditions, including concave bending radii of 110.5 mm and 85 mm as well as convex bending radii of 77.5 mm and 38.5 mm. Combined with the Ø-related mechanical analysis of the maximum strain in the critical layers and the practical investigations of electrical parameters, the encapsulated MOSCAPs with Ø 160 μm showed the most stable electro-mechanical performance partly due to the optimized position of the neutral mechanical plane. Comparison of the electrical changes in Al2O3/alucone-encapsulated MOSCAPs with Ø 160 μm, Ø 240 μm, and Ø 320 μm showed that it is beneficial to define the gate dielectric surface area of 0.02 to 0.05 mm2 for Si NM-based wearable electronics. These findings are significant for leveraging the practical applications in ultrathin encapsulation strategies for reliable operations of crystalline Si NM-based integrated circuits.

Flexoelectrically augmented triboelectrification enabled self-power wireless smart home control system

With the rapid development of the Internet of Things and artificial intelligence, smart home has emerged to fulfill the security, convenience, and energy-saving issues of modern life. Self-power, multifunctional, and sensitive sensors are one of the key components for the popularization of smart home systems. Herein, a flexoelectric mica crystal is shown to augment the finger touch-driven triboelectric output enough to operate a wireless and multichannel smart home controller. The smart home controller consists of concave mica films, a hand-grip-type vertical mouse, and an Arduino controller. Strain-gradient-dependent contact potential difference measurement and density functional theory calculation show that flexoelectric charge shifts the workfunction and concave bending reduces the effective electron mass in a mica. A portable hand-grip-type flexoelectrically augmented triboelectric nanogenerator (Flexo-TENG) demonstrates the wireless communication of message in real time and the selective operation of home appliances with various functions via a simple finger touch. This work provides important ingredients for the enhanced triboelectric output via flexoelectricity, and for the realization of a convenient, multifunctional, cost-effective, and adaptable smart home control system without batteries.

Reliability Test of 21% Efficient Flexible Perovskite Solar Cell Under Concave, Convex and Sinusoidal Bending

Perovskite solar cells (PSCs) have been considered the new rising star in photovoltaic (PV) technology. However, flexibility is the major limiting factor in PSCs for restraining the potential for wearable applications. Therefore, the flexible-PSC (F-PSC) design is reported and simulated using the Silvaco-TCAD tool. Different bending modes, such as concave, convex, and sinusoidal, including planar structure, have been reported to examine the performance of the proposed device. The influence of bending radius (5 to 20 mm) and bending amplitude (0.5 to 2 mm) is studied and analyzed to optimize the performance of the F-PSC device. It has been obtained that the planar F-PSC delivers higher PV parameters: short-circuit current density (JSC) of 21.9 mA/cm, open-circuit voltage (VOC) of 1.18 V, fill factor (FF) of 79.31% and PCE of 20.5%. Simulated results are obtained regarding PV parameters, JV, and EQE characteristics. The findings of the reported study would significantly provide a way to explore the F-PSC performance with better-bending properties.

Bending strain-modulated flexible photodetection of tellurene in the long wavelength infrared region

Single-element van der Waals material has triggered a booming exploration since its simple theoretical modeling and highly integration ability. Elemental tellurium (Te) has a narrow band gap, high environmental stability and superior photoelectronic properties, making it one of the strong candidate materials for advanced broadband photodetectors. Moreover, its asymmetrical chain structure and inherent anisotropic piezoelectricity lays the foundations for artificial modification by strain-engineering. In this study, the Te-based prototype photodetectors were demonstrated with a stable, strong photoresponse at λ = 10.8 µm at room temperature. The photoresponsivity and detectivity were 9.34 mA/W and 8.63 × 107 Jones and can be enhanced by mechanical bending strain. The convex strain of 0.33 % significantly suppresses the dark current of Te photodetector since the stretching of Te-Te bond increases the inherent electrical resistance, which in turn enhances its photoresponsivity to 1080 %. Besides, we observed the bending direction is closely related to the modulation mechanism. The concave bending greatly improved the effective light absorption by rolling up the flexible device in the direction of light radiation, which dominants the enhanced photocurrent and photoresponsivity reaches 60.03 mA/W. This work demonstrates a feasible approach for enhancing Te-based infrared photodetection through an appropriate mechanical stimulus, and should has immense potential for the flexible applications of piezoelectronics and optoelectronics.

Textured Polyester Fiber in Three-Dimensional (3D) Carpet Structure Application: Experimental Characterizations under Compression-Bending-Abrasion-Rubbing Loading.

In this article, textured polyester fiber was used as pile yarn in three-dimensional woven carpet structures. The properties of developed polyester carpets under various mechanical loading were studied. A statistical method was used to analyze the experimental data. Regression models were proposed to explain the relationships between carpet pile height and density. The study showed that the bending rigidity and curvature of dry and wet polyester pile fiber carpets were influenced by pile height and pile density (indirectly weft density) in that the downward concave large bending curvature was obtained from very dense carpet structures. In addition, the average dry bending rigidity of the carpet was over eight times higher than the average wet bending rigidity of the carpet. The thickness loss (%) and resilience (%) for each recovery period of various polyester carpets were proportional depending on the pile density. It was broadly decreased when the pile density was increased due to the compression load carrying capacity per polyester fiber knot, which was higher in carpets having dense knots compared to sparse knots per area. On the other hand, the polyester pile density and height largely affected the carpet mass losses (%) of all textured polyester carpets under an abrasion load. The number of strokes received after completely fractured polyester pile yarns during a rubbing test were increased when the pile heights for each pile density were increased. Findings from the study can be useful for polyester carpet designers and three-dimensional dry or impregnate polyester fiber-based preform designers in particularly complex shape molding part manufacturing.

The ins and outs of membrane bending by intrinsically disordered proteins.

Membrane curvature is essential to diverse cellular functions. While classically attributed to structured domains, recent work illustrates that intrinsically disordered proteins are also potent drivers of membrane bending. Specifically, repulsive interactions among disordered domains drive convex bending, while attractive interactions drive concave bending, creating membrane-bound, liquid-like condensates. How might disordered domains that contain both repulsive and attractive domains affect curvature? Here, we examined chimeras that combined attractive and repulsive interactions. When the attractive domain was closer to the membrane, its condensation amplified steric pressure among repulsive domains, leading to convex curvature. In contrast, when the repulsive domain was closer to the membrane, attractive interactions dominated, resulting in concave curvature. Further, a transition from convex to concave curvature occurred with increasing ionic strength, which reduced repulsion while enhancing condensation. In agreement with a simple mechanical model, these results illustrate a set of design rules for membrane bending by disordered proteins.

Kinematics and Convergent Tectonics of the Northwestern South American Plate During the Cenozoic

AbstractThe interaction of the northern Nazca and southwestern Caribbean oceanic plates with northwestern South America (NWSA) and the collision of the Panama‐Choco arc (PCA) have significant implications on the evolution of the northern Andes. Based on a quantitative kinematic reconstruction of the Caribbean and Farallon/Farallon‐derived plates, we reconstructed the subducting geometries beneath NWSA and the PCA accretion to the continent. The persistent northeastward migration of the Caribbean plate relative to NWSA in Cenozoic time caused the continuous northward advance of the Farallon‐Caribbean plate boundary, which in turn resulted in its progressive concave trench bending against NWSA. The increasing complexity during the Paleogene included the onset of Caribbean shallow subduction, the PCA approaching the continent, and the forced shallow Farallon subduction that ended in the fragmentation of the Farallon Plate into the Nazca and Cocos plates and the Coiba and Malpelo microplates by the late Oligocene. The convergence tectonics after late Oligocene comprised the accretional process of the PCA to NWSA, which evolved from subduction erosion of the forearc to collisional tectonics by the middle Miocene, as well as changes of convergence angle and slab dip of the Farallon‐derived plates, and the attachment of the Coiba and Malpelo microplates to the Nazca plate around 9 Ma, resulting in a change of convergence directions. During the Pliocene, the Nazca slab broke at 5.5°N, shaping the modern configuration. Overall, the proposed reconstruction is supported by geophysical data and is well correlated with the magmatic and deformation history of the northern Andes.

Signal-amplified stretchable PVDF kirigami sensor via neutral axis modification

Stretchable sensors with smart materials now open up diversity opportunities by suggesting ways to overcome the limitations of conventional rigid sensors. The performance of piezoelectric devices is highly dependent on piezoelectric constants. Hence, materials with low piezoelectric constants hinder users to obtain signals induced by stimuli. To rectify this problem, there have been numerous efforts to increase piezoelectricity by doping additional materials or through chemical synthesis methods. These two methods have common limitations: low cost-effectiveness and inferior accessibility by scientists from diversity of fields. In this study, we suggest methods to amplify the response of a polyvinylidene fluoride (PVDF) kirigami sensor with a structural approach: neutral axis modification with a backing layer. We introduce two sensor models with a backing layer: single side and both sides backing layer models. In the former model, the backing layer is attached to the outward area of the concave bending section for stress increment; thereby the response of the sensor can be ameliorated. For the latter model, backing layers are attached on both sides; this synchronizes stress types in the concave and convex bending sections. Consequently, it aligns current movement within the sensor. These two methods are simple and the expected results are intuitive as the voltage amplitude changes proportionally to the backing layer thickness. Also, the modified sensor exhibits stable and identical responses during and after 1000 cyclic motions of stretching and releasing with an applied strain of 80%. The maximum voltage amplitude gap between the pristine and modified sensor is marked as 8.36 V, which is a 48% amplified response from the sensor without a backing layer. This method allows users to adjust the voltage response to their demands in a simple way. This modification also has the potential to be applied as a piezoelectric energy harvesting system.

Performance and Stability of Flexible Low-Voltage Organic Transistors on Paper Substrates

Paper has emerged as a potential substrate for biodegradable and sustainable electronics. In this work, high-performance flexible organic transistors on a paper substrate were demonstrated using simply an engineered bilayer gate dielectric consisting of polyvinyl alcohol (PVA) and polyacrylic acid (PAA), which was previously reported by us on flexible plastic substrates. The superstrong hydrogen bonding between PVA and PAA as confirmed through fourier-transform infrared (FTIR) spectroscopy makes it a promising bilayer for solution-processed gate dielectrics, yielding highly reliable flexible transistors. For a −5 V operation, the devices exhibited high performance with a field-effect mobility up to 0.5 cm2 V–1 s–1, a near-zero threshold voltage, a high Ion/Ioff ∼ 104, and high stability as observed through measurements for repeatability, bias stress, and cyclic stability for 500 cycles. High electromechanical stability with negligible variation in performance was achieved upon application of bending in various ways such as concave, convex, and twist bending. Resistive load inverters with these p-channel devices showed decent switching, confirming the suitability of these transistors in circuit applications. Though the performance of the devices was degraded upon heating above 50 °C, the devices exhibited very high environmental stability for more than 30 weeks in ambient conditions. In addition, a high degree of disintegration was observed in these paper devices due to the capability of biodegradability in soil with a biofertilizer.

Out-of-Plane Electronics on Flexible Substrates Using Inorganic Nanowires Grown on High-Aspect-Ratio Printed Gold Micropillars.

Out-of-plane or3Delectronics on flexible substrates are an interesting direction that can enable novel solutions such as efficient bioelectricity generation and artificial retina. However, the development of devices with such architectures is limited by the lack of suitable fabrication techniques. Additive manufacturing (AM) can but often fail to provide high-resolution, sub-micrometer 3D architectures. Herein, the optimization of a drop-on-demand (DoD), high-resolution electrohydrodynamic (EHD)-based jet printing method for generating 3D gold (Au) micropillars is reported. Libraries of Au micropillar electrode arrays (MEAs) reaching a maximum height of 196µm and a maximum aspect ratio of 52 are printed. Further, by combining AM with the hydrothermal growth method, a seedless synthesis of zinc oxide (ZnO) nanowires (NWs) on the printed Au MEAs is demonstrated. The developed hybrid approach leads to hierarchical light-sensitive NW-connected networks exhibiting favorable ultraviolet (UV) sensing as demonstrated via fabricating flexible photodetectors (PDs). The 3D PDs exhibit an excellent omnidirectional light-absorption ability and thus, maintain high photocurrents over wide light incidence angles (±90°). Lastly, the PDs are tested under both concave and convex bending at 40mm, showing excellent mechanical flexibility.

A wing-structured sensor with multiple mechanical stimuli differentiation capabilities toward multifunctional applications

Wearable sensing electronics capable of detecting and differentiating multiple mechanical stimuli are promising devices in the applications of healthcare monitoring, robotics, etc. However, most wearable sensors are developed for detecting only uniaxial mechanical stimuli, which severely hinders their practical applications that usually involve complex mechanical stimuli. Here, a wing-like multifunctional sensor (WMS) consisting of pressure sensing module in the middle and stretching sensing module in both wings is developed with the capability of detecting and differentiating pressure, stretching, convex and concave bending through distinct electrical signals variation trends. The hierarchical in-situ filling porous as pressure sensing layer and micro-wrinkled carbon nanotubes (CNTs)/Ag nanoflakes as stretch sensing layer achieve high sensitivity over a broad range in both pressure (sensitivity of 0.25 kPa−1 at 500 kPa) and strain sensing (Gauge factor of 140 at 150%). The pressure and stretch sensing module can work without interfering with each other, which is realized by structural design of lower Young’s modulus stretch sensing module and higher thickness and compressibility pressure sensing module. Then WMS is demonstrated in accurate detection of human kinesthesia, human-computer interface, identification of objects of various hardnesses and sizes by robotic gripper, and perception of environmental information through a crawling robot.

Embedded Integration of Sb2Se3 Film by Low-Temperature Plasma-Assisted Chemical Vapor Reaction with Polycrystalline Si Transistor for High-Performance Flexible Visible-to-Near-Infrared Photodetector.

Flexible optoelectronics have garnered considerable interest for applications such as optical communication, motion capture, biosignal detection, and night vision. Transition-metal dichalcogenides are widely used as flexible photodetectors owing to their outstanding electrical and optical properties and high flexibility. Herein, a two-dimensional (2D) Sb2Se3 film-based one transistor-one resistor (1T1R) flexible photodetector with high photosensing current and detection ranges from visible to near-infrared was developed. The flexible 1T1R was fabricated using an efficient field-effect transistor platform with the 2D Sb2Se3 film directly deposited on the sensing region using a low-temperature plasma-assisted chemical vapor reaction. The photodetector could achieve a maximum Iphoto/Idark of 15,000 under white light with a power density of 26 mW/cm2, in which the photodetector showed quick rising and falling response times of 0.16 and 0.28 s, respectively. The 2D Sb2Se3 film exhibits broadband absorption in the visible and IR regions, yielding an excellent photoresponse under laser illumination with different wavelengths. To investigate the flexibility and stability of the 1T1R photodetector, the photoresponses were measured under different bending cycles and curvatures, which maintained its functions and exhibited high stability under convex and concave bending at a curvature radius of 20 mm.

Flexible Multi-Element Photothermoelectric Detectors Based on Spray-Coated Graphene/Polyethylenimine Composites for Nondestructive Testing

Photothermoelectric (PTE) detectors receive much attention owing to the superiority of self-powered, non-bias input, and friendly ambient environments, facilitating abundant prospective applications in industrial inspection, medical diagnostics, homeland security, and wearable Internet of Things. However, many drawbacks of currently applicable PTE materials, involving unstable material oxidation, an uncontrollable fabrication process, and unscalable manufacturing, hinder the development of industrial productions. Herein, we demonstrate a vertical graphene/polyethylenimine composite PTE detector fabricated with an optimized spray-coating method in compact alignment on various surfaces, achieving a significant photovoltage detectivity and responsivity of 6.05 × 107 cm Hz1/2 W-1 and 2.7 V W-1 response at a 973 K blackbody temperature radiation (2.98 μm peak wavelength). In addition, the long-term stability and resistible concave and convex bending flexibility are presented. Furthermore, a nondestructive testing system is established and verified through high-spatial-resolution and high-penetration illustration. Overall, the spray-coated and flexible PTE graphene/polyethylenimine multi-elements with broadband infrared absorption compatibility and stable energy conversion are promising candidates for future health monitoring and wearable electronics.

Magnetocaloric effect and tunable phase transition exponents of SrRuO 3/mica heterostructure with varied mechanical bending

Exploitation and enhancement of the mechanical strain to modulate the magnetic properties are crucial for developing conformal wearable magnetic-electronic devices. However, the mechanical strain how to regulate the magnetic properties remains unclear for flexible thin film. Here, (111)-oriented SrRuO3 thin films are epitaxially grown on flexible mica substrates, and the influence of the mechanical bending on magnetic properties is studying by altering the curvature of the SrRuO3/BaTiO3/Mica heterostructure. The results show that the phase transition temperature does not reveal a significant dependence on both of convex and concave bending but they play a contrary role on the magnetic entropy change. Namely, the tensile stress (convex) increases the magnetic entropy change while the compressive stress (concave) decreases it. Moreover, based on the scale analysis method, we find that both bending states are directly correlated with the change of critical phase transition behavior. We think that the variation of domain wall configuration due to mechanical bending is the main reason for the change of magnetic properties. This study therefore not only identifies a strong magnetic property correlation in the mechanical strain, but also offers an avenue to improve flexible electronic devices with optimized performance.

The role of the proto-Alpine Cenerian Orogen in the Avalonian- Cadomian belt

Abstract The proto-Alpine Cenerian orogen (Ediacaran-Ordovician) and the Cadomian orogen (Ediacaran-Cambrian), remnants of which are exposed in the central European Variscides, should be defined as two distinct and spatially separated coastal orogens within the Avalonian-Cadomian belt. The Cadomian orogen originally lay in front of the Sahara metacraton. It underwent a change from an active to a passive margin setting during the Cambrian. The Cenerian orogen, represented by intra-Alpine rocks, was located farther east near the Arabian Nubian Shield, from where it inherited a characteristic Tonian/Stenian detrital zircon signal. Subduction persisted in the Cenerian Orogen until the Ordovician. The Cadomian orogen was akin to Andean type whereas the Cenerian orogen was more akin to Alaskan type. This paper explores why the two orogens have such different characteristics and tectonic evolutions despite their probable proximity in the Avalonian-Cadomian belt. One explanation could be that they were at nearly right-angles to each other due to a strong concave bending of the northern Gondwana margin ahead of the Arabian-Nubian Shield.

Effect of an Adjustable Hinged Carbon Fiber Operating Table on Sagittal Alignment of the Lumbar Spine

This is a prospective study that has been done to assess the lumbar sagittal alignment of patients positioned prone over an adjustable hinged carbon fiber operating table. The following three variations of table position have been considered: neutral, 20° convex, and 20° concave bending. A total of 33 patients who underwent lumbar disc herniation and lumbar canal stenosis surgery were enrolled. Patients who presented with spinal deformity akin to lumbar scoliosis or spondylolisthesis were excluded. For the surgical procedure, following the induction of endotracheal general anesthesia, patients were positioned prone on the adjustable hinged carbon fiber operating table. Radiographs of the lateral view of the lumbar spine were acquired for the three table positions, i.e., neutral, 20° convex, and 20° concave. The lumbar lordosis was measured on radiographs. The lumbar lordosis presented divergently in all three variations of the table (p < 0.01): 45.2 ± 11.0° in neutral; 52.0 ± 10.7° in 20° lumbar extension bending; and 35.9 ± 10.8° in 20° lumbar flexion bending. The efficacy of table bending was 46.5% in convex and 34.0% in concave bending. In conclusion, the lumbar lordosis in three different table positions were 35.9° in 20° convex bending, 45.2° in neutral, and 52.0° in concave bending. The efficacy of table bending was 46.5% in convex and 34.0% in concave bending.

In situ bow reduction during sublimation growth of cubic silicon carbide

Abstract Sublimation growth of cubic silicon carbide (3C–SiC) with diameters of 50 and 100 mm was performed on freestanding homoepitaxial grown seeds. For both seeds and sublimation grown crystals, two different relaxation axes with varying curvature could be observed with the higher bent axis aligned perpendicular to the original wafer flat. A general reduction in the wafer bow independent of the starting curvature and size of the seeds could be observed. Using the X-ray imaging, we could observe in situ that the bow reduction is linked to the growth of new material and cannot be initiated by heat up or cool down processes alone. Raman spectroscopy of the grown crystals revealed that the observed flattening goes along with a tensing of the seeding layers while the surface of the crystals remains free of a stress gradient. A slight concave bending of lattice planes along the main relaxation axis could be observed by high-resolution XRD rocking curve measurements while for the lower bent axis, no lattice plane bending occurred. Full width half maximum values of the (002) reflection showed values as low as 67 arcseconds proofing the possibility to grow large-area, high-quality 3C–SiC using sublimation growth.

Mechanically tunable thickness-dependent magnetic properties of flexible SrRuO[formula omitted] thin films

A series of SrRuO3 (SRO) single crystalline thin films were grown epitaxially on the flexible substrate of fluorophlogopite by using pulsed laser deposition technology with a BaTiO3 (BTO) buffer layer. The temperature and magnetic field dependences on magnetization were measured as the external field which is parallel and perpendicular to the film surface. The results indicate that the magnetic properties of SRO thin films, including Curie temperature TC, saturation magnetization MS, and coercivity HC, are strongly dependent on the film thickness and the bending state. MS increases from 280.63 to 422.39 emu/cm3 as the film thickness increases from 50 to 200 nm while HC decreases from 1.35 to 0.72 T. TC is slightly increased from 155.41 to ∼160 K as the SRO thin films are subjected to convex or concave bending states. The regulation of mechanical bending and the variation of the film thickness exert significant influences on the magnetic properties of the SRO thin films and their potential application in flexible devices.