bluuebunny/crossref_metadata_2025_split huggingface dataset:
Love wave propagation in a smart composite structure of linear and exponential functionally graded porous piezoelectric material
Authors: Vashishth Anil K. , Bareja Umang 
Published: August 2024

Abstract
Functionally graded materials (FGMs) have emerged as a promising avenue for enhancing the performance and longevity of surface acoustic wave (SAW) devices. This importance is gained due to gradual variation in functional properties of FGMs. In this paper, a mathematical model of a piezoelectric layer overlying a functionally graded porous piezoelectric (FGPP) layer resting on the elastic substrate is presented for the study of Love waves. The material parameters of the FGPP layer are considered to vary linearly and exponentially with the thickness of the layer. The solutions of governing equations corresponding to the FGPP layer are obtained by the Wentzel Kramers Brillouin (WKB) method. Dispersion equations are derived for both electrically open and shorted boundaries, linear and exponential gradation in both mechanical and electrical parameters, and for gradation in mechanical parameters alone as well. After numerical computation, dispersion curves are plotted to investigate the influence of wavenumber, type of gradation, extent of gradation, and type of boundaries on the phase and group velocity. The phase velocity decreases with wavenumber and is found more for linear gradation in comparison to exponential gradation. The electromechanical coupling factor is analyzed for different propagating modes of Love waves, in the case when gradation in mechanical properties is considered, the electromechanical coupling factor is greater than that when variation in both mechanical and electrical properties is considered. It is also observed that the tailoring of gradation can help to get the suitable value of the electromechanical coupling factor. The insights obtained from these findings can offer valuable contributions toward advancing the functionality and efficiency of SAW devices, there by bolstering their applicability in various technological domains.
Remanufacturing of low-carbon steel components using WAAM: microstructural, mechanical, and parametric analysis
Authors: Kanishka Kumar , Acherjee Bappa , Chokka Rahul , Anand Pratik 
Published: August 2024

Abstract
This research paper investigates the remanufacturing of low-carbon steel components using wire-arc additive manufacturing (WAAM), aiming to enhance resource efficiency and sustainability in various industries. The study focuses on repairing flat plate test coupons with a pre-fabricated trapezoidal groove using GMAW-WAAM. The microstructural characteristics and mechanical performance of the repaired samples are compared to the base material, and the influence of heat treatment on the repaired parts is also examined. Planned experiments and empirical modeling are performed to analyze the impact of WAAM process parameters on mechanical properties, establishing correlations between parameters and desired performance characteristics. The WAAM-repaired plate demonstrates higher tensile strength and hardness due to strong bonding, and finer grain structure, while annealing reduces tensile strength and hardness. Additionally, the WAAM-repaired annealed plate exhibits improved elongation compared to the WAAM-repaired plate but remains lower than the base plate. Observations revealed that the strength, elongation, and hardness of repaired samples are influenced by WAAM parameters in complex ways, with favorable combinations yielding improved properties.
Enhanced morphological and thermal properties of epoxy composites reinforced with Palm and Prosopis Juliflora fibers
Authors: K Anandavelu , C Ezhilarasan 
Published: August 2024

Abstract
This study investigates the fabrication and characterization of a hybrid epoxy matrix composite reinforced with Palm and Prosopis Juliflora fibers fabricated using the hand layup technique. Three composite samples were prepared with varying weight percentages of palm and Prosopis Juliflora fiber reinforcements: 5% (Sample A), 10% (Sample B), and 15% (Sample C). Sample B having 10 weight percentage each of Palm fiber and Prosopis Juliflora fiber and 80 weight percentage of Epoxy matrix, exhibited superior performance with a tensile strength of 45.5 MPa and a hardness of 86.5 Shore D. Thermal analysis revealed Sample B’s exceptional thermal stability, with distinct decomposition stages observed through Thermogravimetric Analysis (TGA) and Differential Thermal Analysis (DTA). Void content analysis indicated Sample C had the lowest void content at 4.5%. Energy Dispersive x-ray (EDX) Analysis confirmed homogeneous fiber distribution and strong fiber-matrix adhesion, supported by carbon and oxygen peaks. Fourier-transform infrared spectroscopy (FTIR) spectra showed interactions between functional groups, including alcohols, carboxylic acids, and carbonyl compounds. These findings underscore the composite’s potential for high strength, toughness, and thermal stability applications.
Multi-field coupling in the scrape-off layer of tokamak plasma
Authors: Ji Xiaohui , Guo Zhibin , Zhang Yi 
Published: August 2024

Abstract
We study a reduced electrostatic fluid model for the tokamak scrape-off layer, which incorporates temperature gradient and vorticity gradient as two free energy fields. Two scenarios of field coupling are addressed: (1) sheath condition; (2) vortex wave coupling. For the sheath condition induced field coupling, the poloidal

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flow shear is coupled with the temperature gradient. Combining an eigenmode analysis and the nonlinear phase dynamics approach, our findings indicate that in the absence of a vorticity gradient, the overall effect of the sheath condition induced flow shear can either stabilize or destabilize the interchange mode, depending on the competition between the flow shear suppression and the temperature gradient driving. This is different from the case where the gradient drive and shear damping are decoupled. When the field coupling is mediated by wave interactions, by setting an idealized step-like temperature and vorticity profiles, a joint mode forms through resonant interaction between the interfacial waves driven by the temperature and vorticity gradients, respectively. Near the phase locking condition, the joint mode can be more unstable than pure temperature gradient driven mode.
Research on the energy performance of gun propellant formulations containing 3,5-bis(azidomethyl) isoxazole (BAMIO)
Authors: Ren Jiatong , Cui Pengteng , Zhang Heng , Yang Weitao 
Published: August 2024

Abstract
In order to evaluate the application value of 3,5-bis(azidomethyl) isoxazole (BAMIO) as a heterocyclic azido plasticizer in low-ablation gun propellant formulations, the energy performance of gun propellants containing BAMIO was studied by calculating the properties of the formulations. The results show that BAMIO content, the solvent-nitrocellulose ratio, as well as the content and ratio of high-energy solid additives all have significant effects on the energetic performance of BAMIO-containing propellant formulations, including force capacity, detonation temperature, detonation heat, and specific volume. From equal-force-capacity and equal-detonation-temperature ternary diagrams ulteriorly, the preferable performance of BAMIO-containing propellant formulations using hexogen (RDX) and nitroguanidine (NGu) as high-energy solid additives was calculated to be about 1090 J•g−1 for force capacity and 2750 K for detonation temperature when the content of RDX is not greater than that of NGu. In other words, BAMIO-containing propellant formulations can reduce the detonation temperature by more than 300 K with an even higher force capacity compared with the traditional low-ablation nitroguanidine propellant. It is concluded that BAMIO has certain application prospects in low-ablation propellant formulations, which can be used as an energetic plasticizer in the formulations for further application research.
The research on the geometrical characteristics and microstructure of the cladding track of DZ125L Nickel-based alloy deposited by laser metal direct deposition
Authors: Su Pengsheng , Yang Hao , Zhang Linping , Zhai Yuewen , Ge Yuhan , Yang Xiaozhi 
Published: August 2024

Abstract
This study investigates how variations in laser power, scanning speed, defocusing amount, and powder feeding impact the geometrical characteristics and microstructure of DZ125L nickel-based superalloy. The results show that the weld pool size increases with the rise of laser power, but higher laser power will increase the tendency of hot crack defects. With the increase of positive defocusing, the melting height and depth decrease, but the melting width rises first, then decreases and increases finally. The increase in scanning speed leads to the reduction in melting width and height, while the effect on melting depth is small. With the increase of powder feeding amount, the melting height and depth increase, while the melting width decreases, but too much powder feeding amount leads to some powder being difficult to melt. Increasing laser power or decreasing positive defocusing will lead to a rise in the size and proportion of cylindrical crystals in the molten pool. Increasing scanning speed and powder feeding amount will let the crystal direction of columnar crystal change from <001> to <101>.
Servo control technology for automatic screw-tightening process of robotic arm based on multi-vision sensor
Authors: Liu Zongxin , Xie Wenzhou , Xiao Muzheng , Zhang Zhijing , Jin Xin , Qin Yan 
Published: August 2024

Abstract
This article discusses the servo control technology for the automatic screw-tightening process of a robotic arm based on multiple visual sensors, aiming at the assembly requirements of complex spatial structural components. The study emphasizes the importance of automated screw-tightening processes in industrial automation to improve efficiency and product quality. Image processing and servo technology have been introduced to achieve precise control of the screw-tightening process. The research focuses on developing a distributed architecture to control robot arms and camera modules, process image information, and make servo adjustments based on perception data. Detailed introductions are given to the assembly control system model, visual observation scheme, image processing algorithms for hole recognition and screwdriver posture detection, as well as servo control mechanism. The research aims to improve the efficiency and accuracy of the screw-tightening process through advanced technology integration.
Research on the application of airbag loading technology in the strength test of amphibious aircraft
Authors: Zhuo Yi , Chen Limin , Su Shaopu , Li Shanshan , Chen Xianmin 
Published: August 2024

Abstract
This paper verifies the feasibility of the airbag loading technique to apply hydrodynamic loads on the bottom of large amphibious aircraft. Firstly, CCAR-23 §23.533 is used to calculate the bottom pressure of the ship’s bottom test piece when it is in the water, and then finite element analysis and test verification are used to calculate and measure the stress distribution of the test piece respectively. The analysis results show that the airbag loading technique can meet the requirement of applying hydrodynamic loads for large amphibious aircraft.
Effect of vacuum isothermal high-pressure gas quenching on heat treatment deformation control and hardness of Cr12MoV dies
Authors: Fan Zhenyu , Wang Huizhen , Zhai Yuewen , Jiang Chao , Zhou Leyu , Guo Shuo , Zhang Zibo , Zhan Yuheng 
Published: August 2024

Abstract
Heat treatment produces cumulative deformation of the dies, and it is particularly important to control deformation through appropriate heat treatment processes. The influence of vacuum gas quenching on the heat treatment deformation control of Cr12MoV cold working dies is explored. The heat treatment deformation and hardness of Cr12MoV dies by different heat treatment processes were tested. The dimensional deformation of dies was measured by the three-dimensional detection method. A characterization method for the deformation rate was designed based on the shape characteristics of Cr12MoV dies. The results indicate that the vacuum isothermal gas quenching process contributes to controlling deformation while maintaining the high hardness of the die. The dimensional deformation rate is controlled below 0.05% and the hardness of the sample reached 59.0 HRC after quenching and tempering.
Digital twin method for predicting the critical load of debonding damage in honeycomb sandwich structures based on distributed optical fiber sensor and Dynamic Bayesian Network
Authors: Chen Shuai , Xu Hao , Wu Zhanjun 
Published: August 2024

Abstract
During the service life of aerospace vehicles, harsh environmental conditions such as vibrations and impacts can easily lead to the partial debonding of honeycomb sandwich structures. Distributed optical fiber sensors (DOFS) based on backscattered Rayleigh scattering are widely used in the field of structural health monitoring due to their advantages of easy embedding and high anti-interference capabilities. How to timely detect debonding damage and predict the structure’s critical safety load to ensure the safety of the vehicle’s structure has always been a concern for researchers. This paper proposes a method combining Optical Frequency Domain Reflectometry (OFDR) DOFS, finite element simulation, and Bayesian probability to predict the critical load of debonding (both current and future). Herein, the optical fiber is used for online length identification of debonding damage, while finite element simulation employs a cohesive zone model (CZM) to provide reliable prediction results. The Bayesian approach utilizes a combination of Dynamic Bayesian networks (DBNs) and improved particle filtering to calibrate parameters of the simulation model based on debonding observation data. To verify the feasibility of the method, model analysis was conducted on data from asymmetric cantilever beam tensile tests on honeycomb sandwich structures. The results demonstrate that the architecture proposed in this paper can accurately predict the critical load of debonding in honeycomb sandwich Structures, providing strong support for predicting the evolution of debonding damage in aerospace structural monitoring.
Preparation and characterization of silica sol-impregnated glass fibers
Authors: Liao Tian , Yu Haibo , Huang Yuehan , Zhang Jinming , Li Yan , Xu Anhou 
Published: August 2024

Abstract
Silica sol-impregnated glass fiber products were prepared via the sol-gel method, with tetraethoxysilane (TEOS) as a precursor and hydrochloric acid (HCl) as a catalyst, and characterized by 1H NMR, FT-IR, and solid 29Si NMR analyses. The results indicated that the structure of the impregnating agents was significantly affected by the amount of water added. With a decrease in the molar ratio of added water, the degree of TEOS hydrolysis was reduced, and more ethoxy groups -OCH2CH3 were formed, resulting in the formation of sol products with a linear structure. Furthermore, contact angle and water absorption tests showed that as the molar ratio of water increased, the water contact angle decreased, whereas the water absorption of impregnated glass fiber increased. These results indicate that a higher hydrolysis degree of TEOS with more added water generates more Si-OH groups, facilitating the cross-linking of sol products to form a network structure.
An improved approach to decouple the indentation size effect from nanoindentation hardness of ion-irradiated samples
Authors: Qian Qiuyu , Ma Hailiang , Fan Ping , Zhang Qiaoli , Li Ke , Du Aibing , Li Junhong , Feng Wei , Su Xiping , Yuan Daqing 
Published: August 2024

Abstract
Ion irradiation combined with nanoindentation has been widely used to evaluate the irradiation-hardening effect of materials. Depth-dependent hardening resulting from the non-flat damage profile in heavy-ion irradiation, coupled with the indentation size effect (ISE) in nanoindentations, would further increase the complexity of the extraction of irradiation hardening. In this paper, a simple and reliable approach to decouple the indentation size effect from nanoindentation hardness was proposed based on the modified Nix-Gao model with an extended plastic zone. A hardness dependency was introduced in the indentation characteristic length as well as in the plastic zone size, so that their values will smoothly alter with increasing indentation depths and naturally reduce to the values of the unirradiated material when the indentation depth is well beyond the irradiation zone. The indentation size effect in the measured nano-hardness of ion-irradiated samples can be effectively separated out using the proposed method.
An ethanol gas sensor based on floating gate carbon-based FETs with humidity resistance
Authors: Tao Lu , Liu Bohao , Zhang Yong 
Published: August 2024

Abstract
With the continuous development of transportation, the problem of drunk driving has attracted people’s attention. As a key part of the intelligent drunk driving breath detection system, the ethanol gas sensor has many problems, such as poor repeatability and moisture resistance, which limit its practical application. In this paper, a carbon-based field-effect transistor (FET)-type gas sensor with a sensing gate (Au/ZnO) was proposed. The good reproducibility of the sensors fabricated in one batch was beneficial to mass production. Moreover, the gas sensor possessed good stability towards 50 ppm and 190 ppm ethanol, acceptable selectivity, and humidity resistance (response deviation is 3.97% under a humidity environment ranging from 10% RH to 90% RH), indicating the potential in the drunk driving test.
Analysis of the effect of circular spline tooth profile parameters on flexspline gear stress based on response surface methodology
Authors: Ma Honglie , Zhang Tao , Yang Congbin 
Published: August 2024

Abstract
This study presents a simulation model for the wave generator and flexspline assembly, examining the relationship between radial and main section deformations. Adjusting the wall thickness enables interference-free meshing of various sections. A response surface model for the effect of circular spline profile parameters on flexspline stress has been established. To assess how various parameters of the involute gear profile affect the meshing stress of flexspline. Thus providing a theoretical basis for optimizing gear profile modifications.
Stress and fatigue analysis of bellows with volume defects
Authors: Wan Tian , Bai Jinchuan , Chen Deqi , Feng Bo , Feng Tiezhu , Wang Li 
Published: August 2024

Abstract
To evaluate the safe operation of metal bellows expansion joints with volume defects, the stress and fatigue life were studied. In this study, the stress and fatigue characteristics of bellows with volume defects were studied by using the finite element method combining static analysis and nCode fatigue analysis module. The research shows that under the working conditions of internal pressure of 0.9 bar, temperature of 154.5°C, axial displacement of ±20 mm, and transverse displacement of ±18 mm, the stress at the joint of metal bellows expansion joint and straight pipe segment is the largest, and its size is 441.8 MPa. Fatigue analysis under cyclic events shows that the minimum life of the metal bellows expansion joint is 725 cycles. The results of stress and fatigue life obtained by finite element calculation meet the expected requirements. Therefore, the evaluation method established in this paper is suitable for analyzing the stress and fatigue life of bellows expansion joints with volume defects.
Simulation of electrostatic atomization formation process under different water-based nanofluid conditions
Authors: Liu Pan , Su Yu , You Jiaxi 
Published: August 2024

Abstract
The electrostatic atomization effects and performance of different aqueous nanofluids exhibit noticeable differences. In this study, COMSOL software was utilized to simulate the electrostatic atomization process of water-based nanofluids containing 0.1 vol.% of graphite, graphene oxide, and Al2O3 under a cone jet voltage of −9 kV and a flow rate of 12 ml/h. The formation process of the cone jet was observed based on volume fraction, and the formation process of nanofluid cone jets and the subsequent breakup of droplets at the tip were analyzed through charge concentration, electric field force, and volume force. The results indicate that the graphite-based nanofluid exhibits a faster formation rate of the cone jet, thorough breakup of droplets at the jet’s tip, and superior electrostatic atomization effects.
Nonlinear finite element analysis for axial load distribution of thread considering plastic deformation
Authors: Chen Wentao , Liu Zhifeng , Chu Hongyan , Yan Xing , Li Ying 
Published: August 2024

Abstract
Due to the localized high stress transmission and plastic deformation uncertainties, certain threads at the root of fasteners may experience extremely high stress in threaded connections, potentially leading to structural strength failure and premature fatigue. This study proposes an analysis method for stress distribution considering plastic deformation based on an analytical model of thread axial force distribution within the elastic range. A refined finite element model considering the helix angle of threads was established, and a stress distribution analysis of thread teeth was completed. The accuracy of the finite element model was verified through comparison with theoretical calculations. Additionally, to study the influence of different factors on the axial stress distribution of threads, a finite element model of standard threaded connections was established, in which parameters such as preload level, number of engaged threads, and root radius were taken into account.
Material testing and low cycle fatigue life analysis of supercharger gasket
Authors: Lu Ming , Li Yuntao , Yan Pingtao , Li Qiang , Shao Jian , Zheng Ling 
Published: August 2024

Abstract
Aiming at the cracking problem of the supercharger metal gasket in the development stage of an engine, an analysis method is established. Firstly, the gasket is assumed to be a spring unit, and transient three-dimensional analysis is carried out to obtain the gap movement of the gasket during the whole cycle process. Then, a detailed two-dimensional model of the gasket is established to calculate the low-cycle fatigue life of the gasket structure through loading temperature and gap movement. The data of tensile strength and elastic modulus at different temperatures were obtained by testing the base material of the gasket. The results indicate that the material performance of the gasket drops sharply when it is higher than 400°C to 500°C, and the temperature of the gasket near the supercharger is in this interval. From the life results, it can be seen that the two layers of the gasket have cracks in half of the test, and the cracking problem can be solved by adjusting the material of the two layers.
Thermoelastic damping in parallel piezoelectric bimorph
Authors: Liu Ningning , Zuo Wanli , Liu Xuan 
Published: August 2024

Abstract
Thermoelastic damping (TED) determines the upper limit of the quality factor. The accurate analysis of TED is critical for the design and research of microelectromechanical systems (MEMS). Therefore, the accurate analysis of electromechanical coupling, which is one of the main coupling forms in MEMS systems, on TED is also of great significance. Piezoelectric materials facilitate the interplay between mechanical stress and electrical energy by the piezoelectric effect, thus enabling the synergistic integration of electromechanical systems. In this paper, an analytical model of TED for a parallel piezoelectric bimorph is proposed, and the convergence of the model is analyzed. The difference of TED on the thickness of the beam at fixed aspect ratios and fixed lengths, as well as the influence of piezoelectric effect and boundary conditions on TED, are discussed.