最新刊期
卷 47 ， 期 7 ， 2025
- 摘要：Porous metals are widely used in filtration, catalysis, adsorption and heat transfer because of their excellent mechanical properties. However, creep failure is a primary failure mode for porous metal parts experiencing the high temperature and constant stress. The research progress of the creep resistance of porous metal materials was summarized from four aspects, pore structure， edge structure, micro-defect and creep life prediction. The effects of pore structure, such as porosity, pore shape and pore diameter, on the stress index, creep resistance and deformation mechanism of porous metals were expounded. The creep resistance of the hollow and solid edge under different stress conditions was analyzed, and the effect law of edge size on the creep rate of porous metals was revealed. The effect of micro-defects on the creep mechanism of porous metals was clarified, and the constitutive model for predicting the creep life of porous metals was introduced. These studies provide scientific guidance for the long-life service and reliable operation of porous metal structures.关键词：Porous metal;Creep strength;Porosity;Edge structure;Micro-defect3|0|0更新时间：2025-07-10
- 摘要：Aiming at the vibration fatigue problem of the battery box of electric vehicles, based on the test loads in the real vehicle test field, the fatigue performance of the battery box was compared and analyzed based on single-axis and multi-axis (sequential loading, coupled loading) vibration loads. Firstly, the three-directional acceleration loads were collected at the sensitive points on the battery box in the test field. The power spectral densities were fitted and compared in the same direction of the loads at different measurement points respectively, and the power spectral densities were accelerated through the frequency-domain damage equivalence method to obtain the distribution characteristics of the random vibration three-directional acceleration power spectral densities under the test field specification. Secondly, based on the theory of random vibration fatigue analysis, the multi-axis sequential excitation and multi-axis coupled excitation of the battery box were constructed. Based on fatigue damage equivalence, a uniaxial strengthening spectrum excitation was constructed. Finally, the fatigue damage of the battery box under three kinds of excitation was compared and analyzed by the numerical simulation. The results show that the damage locations of the battery box are consistent under the three excitations. The damage under multi-axis coupled excitation is greater than that under multi-axis sequential excitation, and the single-axis enhancement spectrum has a better reproduction effect on the multi-axis coupled damage. This can provide guidance for conducting rapid vibration fatigue tests of battery boxes based on uniaxial enhanced load spectra.关键词：Enhanced load spectrum;Multi-axis coupling;Accelerated test;Fatigue damage;Battery box2|0|0更新时间：2025-07-10
- 摘要：To investigate the mechanical properties of woven composite hybrid bonded/bolted joints, a mechanical failure model for hybrid bonded/bolted joints based on 3D progressive damage model and cohesive force model was developed to simulate the mechanical behavior and damage evolution of the joints.Based on the Abaqus finite element software, a finite element simulation model for hybrid bonded/bolted joints woven composites was established. The damage initiation and propagation of the composite material were judged using the three-dimensional Linde criterion. The cohesive force model was used to simulate the damage failure process of the adhesive layer. On the basis of test verification of the model accuracy, the strength and damage failure process of the joints were analyzed under different tightening torques. The test and simulation results indicate that as the tightening torque increases, the extension of adhesive layer damage can be effectively suppressed. However, the shear strength of the adhesive layer in the hybrid bonded/bolted joints firstly increases and then decreases, because increasing the tightening torque can reduce the peeling stress of the adhesive layer in the joints. However, the excessive tightening torque will strengthen the stress around the adhesive layer hole, leading to a decrease in the shear srength of the adhesive layer and a decrease in the strength of the connection structure. The load-displacement curve of the numerical simulation is consistent with the test results, and the predicted adhesive layer fracture load is equivalent to the test results. At the same time, the fiber damage, matrix damage, and delamination damage on the laminated plate can also be well reflected in the numerical model, which is similar to the damage form after the connection test, verifying the effectiveness of the damage prediction model.关键词：Composite material;Hybrid bonded/bolted joint;Finite element analysis;Shear strength of adhesive layer;Damage evolution2|0|0更新时间：2025-07-10
- 摘要：The eccentric installation of high-lock titanium alloy bolts (an assembly angle between the bolt head and the fastening plate) leads to premature failure, which seriously affects the safe operation of aerospace aircraft. Currently, the test research is difficult to obtain the bolt fracture process, which in turn limits the revealing of fracture mechanism. Meanwhile, test research cannot obtain the fracture strength variation value of bolts with different assembly angles. Therefore, in response to the problem of premature fracture of high-lock bolts in the eccentric installation, finite element analysis method was employed and the model was verified by test. The verified finite element model was used to visualize the fracture process of eccentric installation bolts and predict the tensile strength of eccentric installation bolts with different angles. The research results indicate that the tensile strength and fracture position of bolts with installation angles of 0° and 3° obtained from finite element analysis are consistent with the test results, which show that the finite element model has good accuracy. As the installation angle increases, both the bolt head and thread are subjected to eccentric loads, and the bending moment generated aggravates the stress concentration in these two areas. When the assembly angle is less than 3°, the stress at the thread is larger, and when the angle is over 3°, the stress on the head is greater. The finite element model successfully predicts the tensile strength of bolts with an assembly angle of 1°, 2°, and 4°. The research results effectively reveal the fracture mechanism of high-lock titanium alloy bolts under the eccentric load. Meanwhile, the simulation model can predict the tensile strength of bolts under different installation angles, and provide technical specifications for the service of eccentric bolts.关键词：High-lock bolt;Finite element analysis;Assembly angle;Fracture mechanism;Prediction of tensile strength2|0|0更新时间：2025-07-10
- 摘要：The subsurface damage depth of grinding WC-10Co-4Cr coating with a cup wheel was investigated in an effort to address the issue that the subsurface damage will cause the coating's performance to deteriorate. The theoretical formula of single particle grinding force was obtained based on the principles of indentation fracture mechanics and grinding material removal theory. A theoretical subsurface damage depth prediction model was developed based on the cup wheel's surface grinding properties. The design of the single factor surface grinding test and the single point polishing test was to confirm the model's accuracy. Analysis was done on how various grinding parameters affected the workpiece's surface roughness and depth of subsurface damage. The maximum relative error is 15.8%, and the predicted subsurface damage depth agrees with the measured value, according to the results. Surface roughness and subsurface damage depth rise with feed speed and grinding depth, but fall with spindle speed. The study has some theoretical significance for directing the process parameter optimization of cup wheel grinding of WC-10Co-4Cr coatings.关键词：Cup wheel;Hard alloy coating;Single factor test;Single point polishing test;Subsurface damage depth2|0|0更新时间：2025-07-10
- 摘要：The disc spring will bear the cyclic displacement load during using, resulting in the fatigue damage and the stiffness degradation of the disc spring, which causes irreversible influence on the compensation function when accumulated sufficiently to cause fracture. Therefore, the disc spring material which occurred internal fatigue and structural stiffness degradation was studied under the cyclic load. By considering characteristics of the geometric nonlinearity and the action of the cyclic load, based on the traditional stiffness degradation model, a stiffness degradation model fitting for disc springs was established.The force change of the structural system, the law of stiffness degradation of the disc spring, and the stiffness degradation model were analyzed and verified with the finite element software. The model was modified based on the test data to obtain the model that can be used to calculate the degradation of the disc spring stiffness. This model can predict the deformation of disc springs’ structure in service, and determine the fatigue damage and performance degradation degree, which can provide some basis and reference for the application of disc springs.关键词：Displacement load;Disk spring;Fatigue damage;Stiffness degradation;Elasto-plasticity2|0|0更新时间：2025-07-10
- 摘要：Metro gearbox is a key component for torque transmission in vehicles, and its failure will directly affect the safety of train operation. The vibration characteristics of tooth breakage faults in metro gearbox were studied by combining dynamic simulation and vibration test. Firstly, based on the dynamic relationships and constraint characteristics between various components of metro gearbox, a rigid-flexible coupling dynamic model of metro gearbox with tooth breakage faults was established through the impact function method, Coulomb friction model, bearing modeling, flexible body of the housing and gear system dynamics theory. The dynamic response of the gearbox under different types of tooth breakage faults was studied, and the influence of operating parameters on the vibration characteristics of tooth breakage was analyzed. Then, through vibration test, the dynamic response of metro gearbox under normal state and broken tooth fault was obtained, verifying the accuracy of the dynamic simulation model. The results indicate that the rigid-flexible coupling dynamic model can effectively calculate the acceleration response of gearbox in different operating states, provide diagnostic basis for the prediction and identification of tooth breakage faults in the gearbox.关键词：Metro gearbox;Tooth breakage fault;Dynamic response;Vibration test2|0|0更新时间：2025-07-10
- 摘要：As a common material for flow components, 17-4PH(0Cr17Ni4Cu4Nb) martensitic stainless steel is vulnerable to serious cavitation damage. Based on the corrosion inhibition effect of array texture structure， this study focused on the cavitation characteristics and inhibition mechanism of 17-4PH material under the surface structure of hundred-micron groove array. Based on the ultrasonic cavitation test platform, the experimental data were obtained by the weight loss method, and the data points were fitted by Logistic equation to obtain the nominal incubation period and other parameters. The results show that the surface groove target with groove spacing W and groove width L in the range of hundred-micron has a good inhibitory effect on cavitation damage. The geometric parameters of the groove array structure with the appropriate ratio can further reduce the cavitation damage of the material. The groove array target with groove width L=700 μm and groove spacing W=400 μm has the longest incubation period (22.79 h) and the smallest cumulative mass loss (10.92 mg) after continuous cavitation for 50 h, thereby exhibiting the best cavitation resistance. This study can provide reference for practical engineering applications in preventing cavitation erosion.关键词：Array groove;Weight loss method;Logistic equation;Cavitation resistance performance2|0|0更新时间：2025-07-10
- 摘要：The rapid assessment method for metal fatigue performance based on the infrared thermography presents advantages such as short testing cycles, low costs, and high efficiency. However, accurately quantifying factors influencing the dissipation of energy, such as convective heat transfer and thermal radiation, proves challenging. The difficulty leads to complications in achieving the precision necessary to meet test standards in the final assessment results. A mixed-hardening constitutive model for 304 stainless steel was established and coupled with the low-cycle fatigue thermomechanical mechanism, to analyze the evolution pattern of dissipated energy caused by convective heat transfer and thermal radiation during the loading process. Furthermore, the impact of low-cycle fatigue loading frequency on the rapid assessment results of fatigue performance was explored based on the critical threshold of dissipated energy. The research indicates that during the low-cycle fatigue process of 304 stainless steel, the dissipated energy from convective heat transfer and thermal radiation constitutes over 54% of the total dissipated energy. Moreover, this proportion continuously increases with the augmentation of the convective heat transfer coefficient. Therefore, it is crucial not to neglect these factors in dissipated energy assessment calculations. With an increase in loading frequency, the peak load narrows within the region of action time. Consequently, the dissipated energy of each load cycle decreases, leading to a rapid assessment result of fatigue performance that tends to be larger than the test value.关键词：Mixed hardening model;Dissipated energy;Thermal convection;Heat radiation;Loading frequency2|0|0更新时间：2025-07-10
- 摘要：The fatigue limit of 7085 aluminum alloy was tested by four-point bending fatigue test for samples of different sizes and roughness.The results show that the greater the thickness of the specimen, the greater the ultimate fatigue strength of the material. The higher the surface roughness of the sample, the lower the ultimate fatigue strength of the material. The stress analysis and calculation of the specimen show that the dangerous cross section occurs at the position where the indenter contacts the specimen, where the specimen is subjected to the combined action of bending normal stress and shear force. With the increase of the thickness of the specimen, the shear force on the specimen decreases, and the bending normal stress on the specimen increases under the same fatigue limit. And vice versa. The relation between the surface roughness and the radius of curvature of the sample is shown by establishing a simplified model, and then the relationship between the surface roughness and the fatigue ultimate strength of the material is obtained.关键词：7085 aluminium alloy;Four-point bending test;Fatigue limit;Sample thickness;Roughness2|0|0更新时间：2025-07-10
- 摘要：After low-velocity impact at the edge, delamination and matrix extrusion occur inside the composite laminates, which will have a serious impact on the safe use and life of the composite laminates. Therefore, it is of practical engineering significance to establish a fatigue life prediction model for low-velocity impact at the edge. The dent damage size, compressive residual strength and fatigue life of the fatigue life prediction model were obtained by low-speed impact test, compression test and compression-compression fatigue test. Based on the average stress failure criterion, the impact damage area of the laminated plate was equivalent to the corresponding aperture by combining the opening equivalent method, and the equivalent damage coefficient of different impact energy was proposed. A fatigue life prediction model considering the compressive residual strength of impact damaged laminates was established, and the prediction results were compared with the test results. The results show that the fatigue life prediction accuracy of the model is high, the error is controlled within 10%, and the model has good prediction ability.关键词：Composite laminate;Fatigue life prediction model;Opening equivalent method;Low-velocity edge impact2|0|0更新时间：2025-07-10
- 摘要：Sprocket chain ring drive system is the core component of scraper conveyors. The wear of sprocket chain socket is one of the main fault of scraper conveyors. Started with the analysis of the meshing transmission characteristics of the sprocket chain socket, constructed the Archard linear wear model, calculated the wear depth of the chain socket’s linear under working conditions, measured the wear depth of the actual wear sprocket, and verified the accuracy of the Archard linear wear model. The deformation model of ring chain was constructed by finite element method, the shape change of chain socket busbar was predicted, and the shape of sprocket tooth surface after wear was reconstructed according to the change of direction and busbar. The influencing factors of chain socket wear were analyzed. The results show that increasing the hardness of sprocket material, reducing the chain speed, the load and the laying angle can reduce the chain wear. This study provides a basis for the study of the wear pattern of sprocket chain of scraper conveyors.关键词：Wear of chain sockets;Meshing transmission characteristic;Archard linear wear model;Deformation model of a circular ring chain2|0|0更新时间：2025-07-10
·Fatigue·Damage·Fracture·Failure Analysis·
- 摘要：Auxetic materials have garnered attention due to their novel behavior under deformation and numerous other material properties, such as fracture resistance, shear resistance, and energy absorption. By integrating hyperelastic materials with auxetic structures, the highly deformable capability enables the design of structures with enhanced mechanical tunability. To this end, a design methodology for 3D printed auxetic structures with improved mechanical adjustability was proposed. The in-plane compressive behavior of the designed structures was investigated through test and numerical analyses. The results demonstrate that, compared to conventional auxetic structures, the composite material with auxetics structures exhibits higher stiffness and enhanced energy absorption performance. By further adjusting the distribution and amplitude of sinusoidal ligaments, auxetic structures with tunable energy absorption, Poisson ratio, and deformation modes were generated. This study presents a design approach for improving the mechanical properties and energy absorption of lightweight structures.关键词：Negative Poisson ratio;3D printing;Auxetic structure;Composites;Energy absorption2|0|0更新时间：2025-07-10
- 摘要：Aiming at the inaccuracy of the finite element analysis (FEA) of heavy-duty engineering wheels under the radial loading condition, a new simulation analysis model based on the results of wheel-tire contact pressure test was established. Firstly, a stress data corresponding to the wheel under inflation pressure condition alone undergo testing, and a loading model for inflation pressure was formulated using a Gaussian function of 4th order. Secondly, a stress data collected while the wheel experiences combined inflation pressure and radial load were analyzed. The influence of inflation pressure was isolated, allowing for the development of a circumferential loading model and an axial loading model for the radial load, using a Fourier function of 4th order and a sinusoidal function of 4th order, respectively. Finally, the validation of the loading model was conducted through Ansys simulation. The outcomes demonstrate the calculation error of mere-approximately 1.943% in relation to the measured data for the key calibration points. Additionally, the observed stress distribution manifests a remarkable degree of consistency. This substantiates the accuracy and reliability inherent in the proposed radial contact pressure distribution model.关键词：Steel wheel;Radial load;Contact pressure distribution;Finite element analysis;Simulation calculation model2|0|0更新时间：2025-07-10
- 摘要：The calculation of bending strength for spiral bevel gears is complex, making accurate evaluation extremely challenging. Focusing on the two distinct calculation methods, B1 and B2, as outlined in the ISO 10300 standard, this study begins with the computational principles of both approaches. It compares the selection methods and numerical application principles for parameters involved in calculating root bending stress and allowable bending stress under both methods. The influence of parameter values on root bending stress calculations is analyzed for each method. Through computations on multiple design samples, the root bending stress values derived from both methods are compared. Finite element analysis is employed to validate the computational results. The findings indicate that due to differences in the types and values of correction coefficients used, there are certain discrepancies in the bending strength evaluation results obtained by the two methods. Method B1 yields a more conservative evaluation of root bending strength, with root bending stress approximately 5% lower than that calculated by Method B2. Although the ISO calculation standard accounts for load sharing among multiple teeth, it overlooks the combined effects on root bending stress, leading to deviations from finite element analysis results. Method B1 shows closer agreement with finite element results, with an error margin of about 6%.关键词：Spiral Bevel Gear;ISO calculation standard;Root bending stress;Finite element analysis0|0|0更新时间：2025-07-10
- 摘要：In order to investigate the stress concentration phenomenon and analyze the distribution characteristics of the interlaminar stress in the hole edge region of composite laminates. Based on the generalized mixed variational principle, the generalized mixed finite element model for laminated plates with various stacking modes were established. The stress field variables were divided into the interlaminar stress and the in-plane stress, with the introduction of stress boundary conditions to ensure the physical continuity of interlaminar stresses between layers and the discontinuity of in-plane stresses between layers. The interlaminar stresses at the edge of the laminated plate hole were respectively analyzed through the thickness direction and the circumferential direction. Numerical examples demonstrated that the incompatible generalized mixed element could obtain more accurate stress singularity results than the 8-node three-dimensional solid incompatible displacement element results solved by the finite element software Abaqus. Stresses on both upper and lower surfaces of the laminated plate consistently reflected actual situations. The research indicates that compared with the displacement element, the incompatible generalized mixed element can more effectively capture the high stress gradient of the interlaminar stresses at the edge of the laminated plate hole, which provides a new idea for the optimal design of the laminate.关键词：Laminated composites;Interlaminar stress;Incompatible generalized mixed element;Stress boundary condition;Stress singularity2|0|0更新时间：2025-07-10
- 摘要：Negative Poisson ratio structures are widely applied in various engineering fields due to their excellent mechanical properties. By combining the star-shaped honeycomb structure with the re-entrant structure, a novel re-entrant angle-type negative Poisson ratio honeycomb structure is proposed. Firstly, the unit cell structure was simplified and analyzed based on symmetry, and the analytical expressions for the Poisson ratio and equivalent elasticity modulus of the structure were derived using the energy method. Secondly, the vertical compressive mechanical properties of the structure were investigated using Abaqus finite element software, and the numerical simulation results were compared with the theoretical calculations to validate the accuracy of the analytical expressions. Finally, the influence of different geometric parameters of the unit cell structure on the equivalent Poisson ratio and equivalent elasticity modulus was discussed, and the equivalent mechanical properties of the structure were compared with those of conventional star-shaped honeycomb structures. The results demonstrate that the proposed structure exhibits favorable negative Poisson ratio characteristics, and its equivalent mechanical properties can be adjusted by modifying the geometric parameters. The findings provide valuable insights for the design of novel negative Poisson ratio metamaterials.关键词：Internal concave angle honeycomb structure;Energy method;Cellular structure;Mechanical property;Negative Poisson ratio0|0|0更新时间：2025-07-10
- 摘要：Constitutive analysis of steel wire rope conveyor belt is a key problem for conveyor belt design optimization and energy conservation. Maxwell model and Burgers model based on viscoelastic theory and transient dynamics were constructed. Considering the fretting friction damping between steel wires and the mutual damping between steel wire rope and conveyor belt, a mixed constitutive model was constructed. Under the condition of 0-30 ℃, the relationship between the parameters of the constitutive model was established, the simulation curve was fitted and solved by Matlab, and the accuracy of the mixed constitutive model was verified by taking 40 ℃ as the control group. The verification results show that the maximum error between the conveyor belt represented by this constitutive model and the experiment is 5.88%, demonstrating that this constitutive model can better characterize the rubber conveyor belt with steel wire rope core. The universality of this model is verified by the method of simulation and prediction. It provides a theoretical basis for the structural optimization and energy-saving analysis of conveyor belt.关键词：Mixed constitutive model;Mutual damping;Wire rope conveyor belt;Temperature effect32|103|0更新时间：2025-07-10
- 摘要：A theoretical model of composite metal rubber (C-MR) was established on the basis of static mechanical test. A novel preparation process was used to prepare C-MR, which was subjected to static mechanical tests. The mechanical model of C-MR was established by combining the static mechanical models of wove-metal rubber (W-MR) and tangled-metal rubber (T-MR), and the effects of different knitting and winding ratios on the mechanical properties of C-MR were investigated. The comparison between the test data and the theoretical model shows that the theoretical model can predict the mechanical properties of C-MR effectively. The results show that the knitting and winding ratio has a significant effect on the mechanical properties of C-MR, and the larger the knitting and winding ratio is, the larger the stiffness and damping properties of C-MR are. The conclusion can provide a theoretical support for the preparation and application of C-MR.关键词：Composite metal rubber;Static mechanical test;Mechanical property;Mechanical model0|0|0更新时间：2025-07-10
·Design·Calculation·
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