Tensile Strain Range Research Articles

Interaction Between Strain and Phase Formation in HfxZr1-xO2 Thin Films.

HfxZr1-xO2 thin films have excellent complementary metal-oxide semiconductor compatibility and scalability compared to other ferroelectric materials. This makes them a promising candidate for non-volatile memory applications. However, the polymorphism of the materials presents a challenge in stabilizing the ferroelectric properties. Since the wake-up free non-volatile memory applications require the presence of ferroelectric properties in the pristine state of the films without additional electric field cycling, it is necessary to understand how to promote the ferroelectric orthorhombic phase formation. In this work, the interaction between in-plane tensile strain and phase formation of atomic layer deposition grown HfxZr1-xO2 thin films with different thicknesses and different compositions is demonstrated. By combining the biaxial in-plane tensile strain with the electric switching field and remanent polarization, it is observed that the best ferroelectric properties correlated with an in-plane tensile strain range of 0.4-0.6%. Moreover, the observed correlation between strain and phase formation indicates that strain exerts an influence on phase formation in the pristine state, and that phase formation, in turn, affects strain during electrical field cycling. This work is expected to be helpful to improve the ferroelectric properties in HfxZr1-xO2 films, which can be processed for different memory devices with specialized requirements.

Stretchable wireless optoelectronic synergistic patches for effective wound healing

Physiotherapies play a crucial role in noninvasive tissue engineering for wound healing. However, challenges such as the implementation of complex interventions and unsatisfactory treatment outcomes impede widespread application. Here, we proposed a stretchable and wirelessly-powered optoelectronic synergistic patch with a dual-layer serpentine wireless receiver circuit to drive the optoelectronic modulation component. Optimized structure and impedance matching enable the patch to seamlessly attach to irregular skin surfaces and operate robustly over a 30% tensile strain range. Based on Sprague-Dawley rat wound model. The wound closure rate of the optoelectronic synergistic group significantly outperformed both monointervention and blank control groups. Mechanistically, optoelectronic synergistic intervention enhances the secretion of vascular endothelial marker proteins and growth factors, and stabilizes mitochondrial function during oxidative stress. Overall, the scalable amalgamation of flexible electronics, wireless transmission, and synergistic interventions promise to improve wound care.

Experiment and prediction of the strain-range dependent ultra-low-cycle fatigue based on micromechanical cyclic void growth model

Under severe seismic action, the local stress concentration region in steel structures is prone to the ultra-low-cycle fatigue (ULCF) under high triaxiality and irregular cyclic deformation with intensively varying strain amplitudes. It emphasizes the necessity of the jointed effects of the stress triaxiality and strain range incorporated in the ULCF life prediction. Given the limited relevant studies in terms of the underlying micro-mechanisms, this paper focuses on experimental and modeling studies of the combined effects of stress triaxiality and strain range on the ULCF failure, based on Gurson-Tvergaard-Needleman (GTN) microvoid evolution theories. Monotonic tensile tests on three types of notched round bars suggest that fracture strain decreases with increasing triaxiality. Cyclic tests on two types of notched bars under various strain ranges confirm the combined effects of stress triaxiality and strain range. Given a specific triaxiality, the ULCF damage accumulation rate increases linearly as the tensile plastic strain range ramps up. For the same tensile plastic strain range, higher triaxiality results in a greater damage accumulation rate. In the modeling studies, the consistency of the GTN and uncoupled damage models has been proven in terms of ULCF failure of structural steel. Based on GTN theories, a new micromechanical cyclic void growth model (GCVGM) is proposed, considering the detailed processes of void nucleation, growth, and coalescence under monotonic and cyclic loadings. Moreover, the joint effects of stress triaxiality and strain range can be explicitly described within a unified framework, without additional empirical assumptions. Based on experimental and simulation results, the proposed GCVGM shows significant advantages over conventional models in accurately predicting ULCF failure under various loading protocols, with low average errors of 2.73 % and −0.91 % for two types of notched bar specimens, respectively.

Highly Stretchable Thermoelectric Fiber with Embedded Copper(I) Iodide Nanoparticles for a Multimodal Temperature, Strain, and Pressure Sensor in Wearable Electronics

AbstractThermoelectric (TE) fibers have excellent potential for multimodal sensor, which can detect mechanical and thermal stimuli, used in advanced wearable electronics for personalized healthcare system. However, previously reported TE fibers have limitations for use in wearable multimodal sensors due to the following reasons: 1) TE fibers composed of carbon or organic materials have low TE performance to detect thermal variations effectively; 2) TE fibers composed of rigid inorganic materials are not stretchable, limiting their ability to detect mechanical deformation. Herein, the first stretchable TE fiber‐based multimodal sensor is developed using copper(I) iodide (CuI), an inorganic TE material, through a novel fabrication method. The dense CuI nanoparticle networks embedded in the fiber allow the sensor to achieve excellent stretchability (maximum tensile strain of ≈835%) and superior TE performance (Seebeck coefficient of ≈203.6 µV K−1) simultaneously. The sensor exhibits remarkable performances in strain sensing (gauge factor of ≈3.89 with tensile strain range of ≈200%) and pressure sensing (pressure resolution of ≈250 Pa with pressure range of ≈84 kPa). Additionally, the sensor enables independent and simultaneous temperature change, tensile strain, and pressure sensing by measuring distinct parameters. It is seamlessly integrated into a smart glove, demonstrating its practical application in wearable technology.

Effect of Jointed Rock Mass on Seismic Response of Metro Station Tunnel-Group Structures

Effect of Jointed Rock Mass on Seismic Response of Metro Station Tunnel-Group Structures

Fracture characteristics and damage evolution of manufactured sand-based ultra-high performance concrete using tensile testing and acoustic emission monitoring

To address the challenges posed by the excessive exploitation of natural river sand, manufactured sand (MS) was used as a substitute material for natural sand to produce manufactured sand-based ultra-high performance concrete (UHPMC). This study aims to investigate the effects of MS replacement ratio, stone powder content, steel fiber content, and steel fiber shape on the fracture characteristics and damage evolution of UHPMC under tensile load through tensile tests combined with acoustic emission (AE) technology. The research results indicated that the stress-strain behavior of UHPMC could be divided into low strain hardening, low strain softening, and high strain softening. The tensile strength and energy absorption of the UHPMC were less correlated with MS replacement ratio. The tensile strength showed a trend of first increasing and then decreasing with the increase of stone powder content, and UHPMC with a 4% stone powder content presented the better tensile strength. The tensile damage process of UHPMC was mainly concentrated in the range of tensile strain from 0.0002 to 0.0025. The microstructure analysis of the UHPMC matrix revealed that an optimal amount of stone powder enhances the bond property between MS and mortar, thereby improving tensile performance. AE monitoring indicated that AE amplitude and AE energy provide sensitive identification capabilities for classifying the elastic state, strain hardening, and strain softening stages of UHPMC. The findings of this study contribute to understanding the fracture characteristics and damage evolution of UHPMC, promoting the engineering application of MS in ultra-high-performance concrete.

Highly stretchable, robust, sensitive and wearable strain sensors based on mesh-structured conductive hydrogels

With the rapid development of wearable electronic devices, flexible sensors, as the core components of wearable devices, have received extensive attention. Manufacturing of the strain sensors with excellent mechanical properties, wide working range, and high sensitivity is crucial for the development of wearable devices. Herein, for the first time we proposed a strategy based on mesh-structured conductive hydrogel to sensitively detect the body movement in a large workable strain ranges, and demonstrated the facile fabrication procedure of the sensors by using a direct ink writing 3D printing technique. Low cost conductive hydrogels were prepared by a simple one-pot method of combining dispersant-free carbon nanocolloids with easily synthesized PVA/TA/PAM. The printing of complex mesh-structured hydrogels was optimized with high fidelity. The strain sensor based on the mesh-structured hydrogel exhibited excellent mechanical properties, of which the maximum failure stress of the honeycomb was 1.28 MPa and the maximum failure tensile strain was 704 %, amazing sensitivity (GF = 32.95 for the tensile strain range of 3.5 %-5%, GF = 21.5 for the tensile strain range of 100 %-120 %), wide detection range, good stability and durability (for 500 tensile cycles, the ΔR/R0 value remained unchanged). In addition, the working mechanism during the stretching process of mesh-structured hydrogels was revealed by combining finite element simulation with microscopic morphology observation. At last, the applications of the mesh-structured hydrogel-based sensors to accurately and reliably detect both subtle physiological signals and large joint movements were soundly demonstrated, endowing the ability of achieving all-round detection of human motion. Our work could provide a universe strategy for fabricating highly ventilated, stretchable, robust, sensitive and wearable strain sensors, which would greatly expand the applications of strain sensors in wearable devices.

Multifunctional Flexible AgNW/MXene/PDMS Composite Films for Efficient Electromagnetic Interference Shielding and Strain Sensing.

With the rapid development of electronic information technology, composite materials with outstanding performance in terms of electromagnetic interference (EMI) shielding and strain sensing are crucial for next-generation smart wearable electronic devices. However, the fabrication of flexible composite films with dual functionality remains a significant challenge. Herein, multifunctional flexible composite films with exciting EMI shielding and strain sensing properties were constructed using a facile vacuum-assisted filtration process and transfer method. The films consisted of ultrathin AgNW/MXene (Ti3C2Tx)/AgNW conductive networks (1 μm) attached to a flexible polydimethylsiloxane (PDMS) substrate. The obtained AgNW/MXene/PDMS composite film exhibited an exceptional EMI shielding effectiveness of 50.82 dB and good flexibility (retaining 93.67 and 90.18% of its original value after 1000 bending and stretching cycles, respectively), which are attributed to the enhanced multilayer internal reflection network created by the AgNWs and MXene as well as the synergistic effect of PDMS. Besides EMI shielding, the composite films also displayed remarkable strain sensing properties. They exhibited a wide linear range of tensile strain up to 68% with a gauge factor of 468. They also showed fast response, ultralow detection limit, and high mechanical stability. Interestingly, the composite films could also detect motion and voice recognition, demonstrating their potential as wearable sensors. This study highlights the effectiveness of multifunctional flexible AgNW/MXene/PDMS composite films in resisting electromagnetic radiation and monitoring human motion, thereby providing a promising solution for the development of flexible wearable electronic devices in complex electromagnetic environments.

High-performance amorphous carbon/PDMS flexible strain sensors by introducing low interfacial mismatch

It is important and challenging to develop environment-tolerant stretchable strain sensors under some harsh environments. Here, amorphous carbon (a-C)/Polydimethylsiloxane (PDMS) sensors were fabricated with the direct-current magnetron sputtering technology, their sensing performances were optimized by adjusting the elastic mismatch between the top a-C film and used PDMS substrate, and their application under a simulated marine atmospheric environment was evaluated. The results showed that the combination of low stress a-C and low elastic modulus PDMS was favorable to improve the sensing performance, the optimal sensor exhibited the maximum gauge factor (GF) of 3026.9, large tensile strain range to 50 %, rapid response (loading delay time 92.3 ms and unloading delay time 24.6 ms), as well as high durability (>5000 cycles). After 120 h salt spray test, the sensor was quite stable and can detect various human movements with both high sensitivity and stability, such as wrist pulse, wrist bending, and finger bending. This work pioneers the elastic mismatch strategy for high-performance a-C/PDMS sensors and confirms their great potential in the practical applications under harsh environments.

Fiber Bragg grating sensor combined with silicone compliant cylinder for orientation identification of three-component geophone

Three-component geophone rotates randomly during oil and gas exploration, which is difficult to orient. There is a severe impact on the subsequent stratigraphic inversion. By fixing the fiber Bragg grating (FBG) sensor to the three-component geophone, the twist angle is the same. The rotation angle of the three-component geophone can be obtained by measuring the twist angle of the FBG sensor. However, the three-component geophone below the FBG sensor stretches the FBG sensor. Therefore, avoiding the effect of tensile strain on the torsional strain, requires simultaneous inversion of the twist angle and stretch length of the FBG sensor. This paper introduces an FBG sensor with simultaneous inversion of torsion angle and tensile length. The sensor consists of two FBGs embedded in the spiral groove of the compliant cylinder. Firstly, the sensing principle of the FBG sensor is analyzed, and developed FBG sensing model for tensile–torsional strain, including FBG by tilting arrangement, the extension of the tensile strain range of the FBG sensor was realized. Secondly, it describes the fabrication process of the FBG sensor, including loading the FBG with pre-stress, making the FBG sensor realize the extension of the torsion angle range. Next, the convenience of inversion is realized by averaging the calibrated strain transfer coefficients. Finally, to verify the effectiveness of this bidirectional helical fiber design and sensing technology, simultaneous torsion and tension tests were conducted on FBG sensors. The experimental results show that the sensor achieves simultaneous torsion angle and tensile length inversion. The maximum torsion angle of the inversion is 180°. The maximum stretch length of the inversion is 10 mm.

Oxygen-terminated Ti3C2 MXene as an excitonic insulator

Excitonic insulators originate from the formation of bound excitons (electron–hole pairs) in semiconductors and provide a solid-state platform for quantum many-boson physics. We determined the excitonic insulator phase of Ti3C2O2 monolayer from its indirect quasiparticle band structure and from the precise evaluation of the relative value of the fundamental bandgap vs the momentum-indirect excitonic binding energy. The excitonic insulator is stable over the ±4% range of compressive and tensile biaxial strain. The energy region relevant for the optical absorption is strongly strain-dependent.

Electrical conductivity of modified fabrics with carbon coating

Using the example of fabrics and knitwear from a mixture of natural and synthetic polymer fibers, the possibility of obtaining polymer compositions intended for the manufacture of electrically conductive elements for aviation, robotics and so-called "wearable electronics" for medical purposes is shown. The mechanical and electrical properties of fibrous compositions filled with carbon dispersions in various allotropic forms in combination with both soluble and insoluble high-molecular compounds in the form of powders or solutions have been studied. Dispersions of various forms of carbon with a close particle size distribution were selected from among commercially available brands of printing pigments and ingredients of rubber and electrical products. Carbon dispersions were investigated: graphite, carbon black and single-walled nanotubes in the form of a stabilized aqueous suspension. The well-known and justified optimal technological methods of introducing electrically conductive ingredients into the composition of composite materials, taking into account the structure and composition of fabrics. The advantage of spraying electrically conductive graphite particles on the surface of fibers and filaments in combination with the application of solutions and dispersions is shown, which makes it possible to obtain compositions for resistors and strain sensors with a sufficient level of strength and elasticity. The stretching diagram of the sensors and the dependence of the electrical resistance of the composition on the elongation with a high degree of confidence can be divided into two linear sections. The first section in the range of relative tensile strain from 2 to 30% is most consistent with practical application. The coefficient of sensitivity to deformation (GF) of a fabric-based strain gauge does not exceed 10 in the range of deformation in the diagonal direction up to 20%, and the coefficient of sensitivity to deformation on knitwear, regardless of the direction of cutting samples from the canvas, is two orders of magnitude higher and is about 950 to a relative elongation of 30% and 90 in the range of a relative elongation of 30÷45%. The maximum strain sensitivity (QF) of laboratory samples based on knitted fabric, with a deformation of less than 30%, is about 1350 kPa-1 and 4900 kPa-1 at maximum elongation%. The hysteresis of electrical properties with multiple deformations does not exceed 4%.

A flexible strain sensor of porous conductive silicone rubber composites prepared from high internal phase emulsion

AbstractIn this work, a stretchable and compressible strain sensor was fabricated from conductive porous carbon nanotubes/polydimethylsiloxane (CNT/PDMS‐P) high internal phase emulsion (HIPE), which was obtained by simple mechanical mixing of CNTs, PDMS, and water. Micropores were uniformly distributed in the PDMS matrix, with diameters mainly in the range of 3–9 μm and averaging 5.3 μm. Due to the confined dispersion of CNTs in the porous PDMS framework, the CNT/PDMS‐P achieved a lower percolation threshold of 0.29 wt%. Compared to the non‐porous composite (CNT/PDMS), its percolation threshold was reduced by 25%. Besides, the CNT/PDMS‐P showed excellent sensitivity and cyclic stability. The sensitivity of CNT/PDMS‐P was 50% higher than that of CNT/PDMS in the tensile strain range of 0%–10%. The stability tests for 1000 loading/unloading cycles showed that the maximum offset rate of CNT/PDMS‐P was 58% lower than that of CNT/PDMS. The sensitivity of CNT/PDMS‐P compression sensor was S = 0.00259 kPa−1, which could detect the stress up to 600 kPa and maintain the standard waveform even after 1000 compression cycles. Finally, the potential application scenarios of the sensor, such as perception of human body limb movement, facial movement, gesture transformation, and human‐computer interaction scenarios, were explored.

High-Performance Hydrogels via Alternate Compression–Decompression

Novel bioapplications of hydrogels draw huge attention to the development of strong and tough hydrogels that are easily obtainable with less chemical additions. Here, we demonstrate that pressure, a basic thermodynamic quantity, could enable poly(vinyl alcohol) (PVA) to effectively form a gel. The resulting hydrogels by alternate compression–decompression (ACD) have tunable superior mechanical properties compared with conventional freeze-thawed (FT) PVA hydrogels. The microstructures of the ACD hydrogels under varying parameters, including compression rate, cycles, and holding time, reveal that either a slow compression rate or cyclic compressions favor the physical cross-linking of such single polymer networks. The mechanical results display a wide range of ultimate tensile strength, tensile strain, and maximum compressive strength of ∼0.3 to 2.5 MPa, ∼200 to 550%, and ∼3 to 7 MPa, respectively. Moreover, the load resistance of such hydrogels can be further trained by low-cyclic strain hardening to a maximum compressive strength of ∼50 MPa, followed by a desirable recovery. Upon cyclic compression, the ACD hydrogels exhibit consistent energy dissipation behaviors. More importantly, the effect of modulation of pressure on the hydrogel’s mechanical properties is very likely universal for other hydrogel systems due to the basic mechanism of pressure-induced gelation for the polymers discussed.

Deformation behavior of auxetic laminated fabrics with rotating square geometry

Auxetic fabrics are becoming a tempting option for many modern textile products due to their unusual deformation behavior under tensile load. In spite of the developments that have been made, it remains difficult to produce auxetic fabrics more efficiently using existing technologies. In this research, a novel type of auxetic fabrics is proposed based on rotating square geometry and manufactured using commercially available raw materials and lamination technique. Rotating square structures with different parameters are firstly produced through laser cutting a frame fabric, and then bonded to a base fabric using a hot-melt adhesive membrane. Tensile tests are conducted on various two-layer and three-layer laminated fabrics to investigate their deformation behaviors and auxetic effects. Results show that the auxetic behavior of the laminated fabrics mainly depends on initial modulus difference between the base material and the laminated frame material and can be affected by the initial intersection angle and size of square units. It is also found that three-layer laminated fabrics are more desirable than two-layer laminated fabrics when it comes to avoiding out-of-plane deformation and extending tensile strain range of auxeticity.

Microstructure evolution and deformation behavior during stretching of a compositionally inhomogeneous TWIP-TRIP cantor-like alloy by laser powder deposition

A TWIP-TRIP high-entropy alloy with inhomogeneous chemical composition was prepared by laser powder deposition (LPD). The microstructure and properties of the alloy were quite different from those of compositionally homogeneous alloy with the same composition produced via electric arc melting + hot forging (EAM-HF) technique. During stretching, deformation twinning occurred under low strain, while FCC-HCP transformation was observed under high strain. The yield strength, tensile strength, and elongation were 425 MPa, 715 MPa, and 83%, respectively. For comparison, a sample with the same chemical composition was fabricated by EAM-HF. While twinning was detected under high strain during stretching, no FCC-HCP transformation was observed. Its yield strength, tensile strength, and elongation were found to be 69.6%, 86.9%, and 90% of those of LPD sample, respectively. In order to discuss the evolution of hardening behavior, a constitutive model based on dislocation density evolution was established, taking the contribution from twinning and FCC-HCP transformation into account. Since deformation twinning could be generated at a moderate speed in a wide tensile strain range and FCC-HCP transformation occurred under high strains, the high strain hardening rate could be guaranteed under high strain, thus avoiding strain localization, which endowed the LPD sample with good plasticity. It was shown to be possible to adjust the mechanical behaviors of alloys by increasing their stacking fault energy span through LPD.

Flexible tensile strain-pressure sensor with an off-axis deformation-insensitivity

The high demand for flexible force sensors with both strain and pressure sensing has attracted considerable attention for various application scenarios, such as electronic skins and smart prostheses. However, successful application of these sensors in real-world is challenging because the performance of the sensors can be severely degraded under applied off-axial deformations (e.g., bending and twisting) and it is also difficult to successfully decouple these signals due to electromechanical crosstalk. Here, we developed an integrated sensor patch (ISP) consisting of a strain sensor insensitive to pressure, bending and twisting, coupled with a pressure sensor insensitive to tension, bending and twisting. Benefiting from the serpentine structure and bionic design of strain sensor material, as well as the inherent rigidity properties of the piezoelectric ceramic, the resulting patch exhibits insensitivity to off-axis sensing with independent tensile strain and out-of-plane pressure sensing capabilities. The patch achieves a wide range of tensile strains (up to 160% with an apparent pressure coefficient of over 1.23) and a wide range of pressures (1 Pa to 100 kPa). We demonstrate that the wearable ISP can interact human gestures with the robotic hand in real time through a fully soft integrated glove and further continuously record wrist activity to verify tensile strain sensing independent of pressure mode. In addition, the ISP successfully captures the subtle strain of less than 20% of eye blinks and the ultra-low pressure of less than 1.2 kPa of unobtrusive exhalation force with low off-axis interference. Moving forward, this strategy of endowing sensors with off-axis sensing insensitivity and decoupled strain and pressure sensing has great potential in human-machine interface (HMI), virtual reality (VR)/augmented reality (AR) user interfaces, and other soft electronics fields.

Bioinspired Stretchable Fiber-Based Sensor toward Intelligent Human-Machine Interactions.

Wearable integrated sensing devices with flexible electronic elements exhibit enormous potential in human-machine interfaces (HMI), but they have limitations such as complex structures, poor waterproofness, and electromagnetic interference. Herein, inspired by the profile of Lindernia nummularifolia (LN), a bionic stretchable optical strain (BSOS) sensor composed of an LN-shaped optical fiber incorporated with a stretchable substrate is developed for intelligent HMI. Such a sensor enables large strain and bending angle measurements with temperature self-compensation by the intensity difference of two fiber Bragg gratings' (FBGs') center wavelength. Such configurations enable an excellent tensile strain range of up to 80%, moreover, leading to ultrasensitivity, durability (≥20,000 cycles), and waterproofness. The sensor is also capable of measuring different human activities and achieving HMI control, including immersive virtual reality, robot remote interactive control, and personal hands-free communication. Combined with the machine learning technique, gesture classification can be achieved using muscle activity signals captured from the BSOS sensor, which can be employed to obtain the motion intention of the prosthetic. These merits effectively indicate its potential as a solution for medical care HMI and show promise in smart medical and rehabilitation medicine.

Magnetically induced robust anisotropic structure of multi-walled carbon nanotubes/Ni for high-performance flexible strain sensor

Multi-walled carbon nanotubes (MWCNTs) are widely used as functional nanomaterials in flexible strain sensing polymer composites. They are expected to exhibit high anisotropy when aligned along a certain direction due to their unique one-dimensional structure, which has a positive effect on enhancing the sensing performance of the original polymer composites. Here, we used a weak curing magnetic field (less than 0.7 T) to induce the self-assembly of MWCNTs in polymer composites to obtain a novel flexible strain sensor with anisotropic structure (MAPC). To further optimize the comprehensive sensing performance, the synergistic effect between MWCNTs and conductive particles was utilized to enhance the sensitivity of MAPC to tensile strain by filling a small amount of nickel nanoparticles (MAPCN). The sensor can measure the tensile strain range up to 720%, with high sensitivity (GF=1768.7, 90%–100% strain), fast response (loading delay time τ1 = 92.2 ms and unloading delay time τ2 = 143.6 ms, 0–10% strain), and high durability (1050 cycles at 10% strain). These important properties allowed MAPCN to accurately monitor human physiological activities, and a gesture recognition system was designed to demonstrate its practical value and potential application prospect in wearable devices.

Direct printing of surface-embedded stretchable graphene patterns with strong adhesion on viscous substrates

The graphene patterns with piezoresistance behaviors, originating from the structural deformation and band-structure shift under strain, represent an attractive characteristic for developing the small strain (<10%) sensors for wearable devices. However, the insufficient adhesion between the patterns and substrates has significantly limited their utility and reliability. Here, the surface-embedded graphene patterns were directly deposited on polydimethylsiloxane (PDMS) surfaces without hydrophilic treatment via the embedded droplet printing (EDP). The viscous PDMS films instead of the solid ones were used as substrates, and the graphene patterns were partly embedded onto the viscous PDMS surfaces. To assess the adhesion performance, a series of tests were performed. In the bending and tensile tests, the patterns strongly adhered to the PDMS films. Further, the patterns had a favorable increase in resistance in the tensile strain range of 0–3.5%. The resistance of the surface-embedded graphene patterns exhibited a negligible change for over 3 min in the ultrasonic bath. Finally, the relative resistance R/R0 remained constant after the first two adhesion tests using a 3M tape. The surface-embedded graphene patterns exhibited a strong adhesion to the flexible/stretchable substrates, indicating the application prospect in the field of flexible devices.