142 results about "Fatigue Intensity" patented technology

The invention relates to the technical field of non-destructive testing, and particularly discloses an aero-engine blade non-destructive flaw detection method for a miniature unmanned aerial vehicle, which comprises the following steps: acquiring stress data of a blade in a use process in real time by using an MEMS sensor, analyzing the data, and identifying a stress concentration area; carrying out real-time monitoring on crack data of the stress concentration area, extracting crack propagation fluctuation characteristics by utilizing a wavelet transform algorithm, and calculating a crack propagation fluctuation index; fatigue strength data of the material is monitored, fatigue failure characteristics are extracted, and a fatigue failure index is generated through a support vector machine algorithm; comprehensively analyzing the crack propagation fluctuation index and the fatigue failure index, and judging whether the blade is in a healthy state or not; and finally, based on the blade health state, determining whether to carry out further detection or maintenance.

The invention provides a multi-axial fatigue damage evaluation method and device for a steel bridge welding seam considering welding residual stress, and relates to the technical field of fatigue strength analysis and service life prediction of a steel bridge structure. The method comprises the following steps: measuring three-dimensional residual stress in a geometric transition area of a steel bridge welding seam by adopting X rays, acquiring heat distribution and surface topography data in combination with infrared thermal imaging and structured light scanning, and realizing multi-source data space alignment based on a unified coordinate system; secondly, random disturbance is applied to the residual stress, stress fluctuation in service is simulated, and a robustness weight risk factor is constructed; the method comprises the following steps: constructing a bimodal deep neural network, adaptively fusing information of an infrared thermal imaging image and a welding seam three-dimensional topography image through an attention mechanism, training a fatigue risk regression model by taking a robustness weight risk factor as a supervision signal, completing prediction of risk factors at all positions, dividing low, medium and high risk levels based on a preset threshold value, and obtaining a fatigue risk prediction result. And accurate grading evaluation of the fatigue damage of the welding seam is realized.

The invention relates to a multi-component alloy fatigue strength evaluation method based on slip localization, which comprises the following steps: acquiring material parameters of a multi-component alloy for a fatigue test, and establishing a micro-scale model on a computer based on the material parameters; carrying out simulated fatigue loading on the micro-scale model by adopting a molecular dynamics simulation means; after simulation fatigue loading enters a steady-state stage, dividing the micro-scale model into a plurality of subunits with the same size, calculating the slip irreversibility of each subunit based on the shear strain of each atom in each subunit, and further calculating the slip irreversibility difference between the subunits; calculating a non-uniform parameter based on the slip irreversibility of each subunit and the slip irreversibility difference; performing normalization and grid removal processing on the non-uniform parameter to obtain a slip localization index; and constructing a fatigue strength evaluation model based on the material parameters and the slip localization indexes.

The invention relates to the technical field of equal-strength design, and provides a high-reliability equal-strength design method and system for an intelligent cubic press, which considers structural characteristics of the cubic press, performs physical field analysis, modeling and simulation, determines deformation, temperature, stress distribution and stress concentration areas of key components, predicts structural crack initiation of the key components, and provides a high-reliability equal-strength design method and system for an intelligent cubic press. Crack propagation simulation is carried out; establishing a fatigue strength life prediction model based on deep learning and a simulation data set; constructing a fatigue strength reliability model, and establishing a mathematical association relationship among fatigue life, fatigue damage and reliability; a reliability calculation index is introduced into multi-objective optimization of the structure, a high-precision numerical solution of reliability robustness optimization design based on structure simulation is developed, and equal-strength design of the cubic press is achieved. According to the method, the optimal combination of design parameters can be obtained, the equal-strength design of parts and the whole machine structure is formed, and development of intelligent, high-precision and large-scale cubic press equipment is promoted.

The invention relates to the technical field of material science and engineering application, in particular to a method for rapidly optimizing fatigue strength of a metal material under different stress ratios. According to the method, the relation among the tensile strength, the stress ratio and the fatigue strength of the metal material is discussed, and the rapid fatigue strength optimization method of the metal material under different stress ratios is established by utilizing a parabolic equation of a P-C model. The method not only considers the nonlinear relationship between the fatigue strength and the tensile strength, but also considers the fatigue sensitivity of different metal materials under various stress ratios, and has scientific significance and engineering value. Besides, the tensile strength critical optimization value sigma bc and the fatigue strength theoretical optimization value # imgabs0 # (namely, the maximum fatigue strength value # imgabs1 # exists when the tensile strength is sigma bc) of the metal material at a certain stress ratio can be obtained through calculation, the optimization direction can be provided for anti-fatigue design, and the optimization efficiency is greatly improved.

The present invention relates to a method for designing a component made of a material, and a method for determining the service life of a component made of a material, based on the fatigue strength of the material, the creep behavior of the material, and the crack threshold of the material, wherein a time-dependent creep fatigue strength is determined based on the fatigue strength and the creep behavior, wherein the time-dependent creep fatigue strength specifies a time limit for a critical fracture mechanical load and thereby determines the service life of the component made of the material.

The invention provides a high-cycle fatigue strength evaluation method based on damage influence, and belongs to the technical field of aero-engines. The method comprises the following steps: performing a high-cycle fatigue test on a to-be-tested material to obtain first high-cycle fatigue strength, and performing a damage fracture test corresponding to a damage type to obtain a damage life, the damage type comprising creep damage and low-cycle damage; determining interruption time on the basis of the damage life, performing a damage fracture test on the basis of different interruption time, then performing a high-cycle fatigue strength test to obtain second high-cycle fatigue strength, and constructing a damage model; constructing a crystal plasticity constitutive model based on the damage model to perform simulation calculation on the to-be-tested material to obtain a simulation damage value; and correcting the first high-cycle fatigue strength based on the second high-cycle fatigue strength and the simulated damage value to obtain an evaluation result of the to-be-tested material. According to the method, deformation mechanisms of different damage types are clearly distinguished, the method is more flexible, interruption time setting refers to influences of different damage degrees, and the method is more accurate, safer and more reliable.

The utility model provides a fatigue strength test device, which comprises a working condition simulation cabin, a first moving mechanism and a second moving mechanism, the working condition simulation cabin is internally provided with a first accommodating space capable of accommodating a corrugated pipe, and the first accommodating space is respectively communicated with a heating medium system and a refrigerant system to form a high-temperature environment or a low-temperature environment; the first moving mechanism is arranged on the top side of the working condition simulation cabin and comprises a first moving part, at least part of the first moving part can be arranged in the first containing space to be connected with one end of the corrugated pipe, and the first moving part can reciprocate in the longitudinal direction relative to the working condition simulation cabin; the second moving mechanism is arranged on the bottom side of the working condition simulation cabin and comprises a second moving part, at least part of the second moving part can be arranged in the first containing space to be connected with the other end of the corrugated pipe, the second moving part can reciprocate in the first direction relative to the working condition simulation cabin, and a gas channel is formed in the second moving part; the gas channel communicates with the gas pressure source and a pipeline of the corrugated pipe to form a high-pressure environment in the pipeline.

The invention discloses a wind turbine generator blade root bolt fatigue strength analysis method and system. The method comprises the following steps that a three-dimensional model for blade root bolt fatigue strength analysis is established and simplified; the model is converted into a finite element model, and contact setting, boundary condition setting and loading setting of all the components are carried out; carrying out finite element calculation to obtain corresponding stresses of key nodes under different load conditions, and drawing a load-stress curve; adopting a rain flow counting method to obtain an amplitude value, a mean value and a cycle index required by fatigue calculation; interpolation is carried out in the load-stress curve, and the amplitude, the mean value and the cycle index of stress are obtained; accumulating the damage quantity values obtained in each stress cycle to obtain the total fatigue damage of the blade root bolt; generating a wind turbine generator blade root bolt fatigue strength checking report; according to the method, the initial gap and the gap judgment radius between the components are adjusted through contact setting, so that the penetration influence caused by large deformation of the model is reduced, and the problem that convergence is not easy due to improvement of the model precision is solved.

The invention provides an additive repair blade high-cycle fatigue limit prediction method based on random defect probability distribution, and relates to the field of aero-engine fan and compressor blade maintenance, and the method comprises the steps: obtaining the defect distribution of a real blade; establishing a prediction model based on a critical distance theory; according to the prediction model, critical distances of the multiple real blades are determined, and a first critical distance is generated; performing defect reconstruction based on the defect distribution of the real blade to generate a virtual blade; obtaining the first high-cycle fatigue strength of the virtual blade according to the defect distribution of the virtual blade, the first critical distance and the prediction model; respectively determining a plurality of defect parameters and a Pearson coefficient of the first high-cycle fatigue strength, and screening a first parameter significantly related to the first high-cycle fatigue strength; constructing a fatigue strength evaluation model; and inputting the first parameter into the trained fatigue strength evaluation model, and outputting the predicted high-cycle fatigue strength. According to the scheme, the high-cycle fatigue limit of the blade can be quickly predicted, and the prediction accuracy is improved.

The invention discloses a blade vibration fatigue strength and three-dimensional fatigue crack propagation prediction method which comprises the following steps: carrying out uniaxial tensile test and fracture toughness measurement on a blade test piece material to obtain material mechanical parameters of the blade test piece material; performing a bending vibration fatigue test on the blade test piece to obtain the fatigue strength of the blade test piece; a three-dimensional fatigue fracture phase field model is constructed, and phase field simulation parameters are obtained through finite element calculation; based on material mechanical parameters and phase field simulation parameters, a blade three-dimensional simulation model is established by simulating a blade sample in a bending vibration fatigue test, a periodic pressure load is applied to a blade basin of the blade to simulate an aerodynamic load in the service process of the blade, the three-dimensional fatigue crack propagation behavior of the blade is calculated, and the vibration fatigue strength of the blade is predicted. According to the method, a three-dimensional fatigue fracture phase field model is established, numerical solution is performed by using a finite element method, the three-dimensional fatigue crack propagation behavior of the blade under the periodic vibration load can be effectively predicted, and the blade fatigue prediction accuracy is improved.

The invention discloses a device and a method for testing fatigue strength of an outer material layer of an inner shell of a reaction kettle, and relates to the technical field of testing the outer material layer of the inner shell of the reaction kettle. The workbench is further provided with a butt joint and online detection mechanism located on the right side of the feeding mechanism. The butt joint and online detection mechanism comprises a vertical plate fixedly arranged on the table top of the workbench and a transverse plate fixedly arranged at the top end of the vertical plate, an L-shaped plate is arranged on the bottom surface of the transverse plate, a guide column slidably penetrates through the interior of a vertical plate of the L-shaped plate, a horizontally-arranged rack is fixedly arranged at the left end of the guide column, and a supporting plate inclining leftwards and downwards is fixedly arranged on the front end face of a gear. And a microswitch is fixedly arranged on the bottom surface of the lower end part of the support plate. The device has the beneficial effects that the working intensity of workers is greatly reduced, and the fatigue strength testing efficiency of the material layer of the reaction kettle is greatly improved.

The invention provides a platform door optimization method and system and a storage medium, and the method comprises the steps: obtaining a pneumatic pressure change curve of a basic platform door under a train station-crossing working condition according to a pre-trained pneumatic effect calculation model, performing modal analysis, statics structural strength analysis and fatigue strength analysis on the basic platform door according to the pneumatic pressure change curve, and then converting the basic platform door structure into density variable distribution through a variable density method; the target platform door structure is obtained by iteratively updating density variable distribution according to a preset stress constraint condition by taking structural lightweight, rigidity maximization and fatigue life maximization as targets through a genetic algorithm; and target material performance parameters of the target platform door structure are selected in a preset material database through a Bayesian optimization algorithm and a finite element analysis result under the minimum cost constraint condition.

The utility model belongs to the field of fatigue strength test of metal materials, and particularly relates to a clamping device suitable for tension-tension fatigue performance test of linear materials, which is characterized in that a fatigue machine connecting sheet is fixed on a fatigue machine, and the load is reset; the long-rod bolt, the springs and the sample upper clamp are assembled, so that the resultant force of the pre-pressure of the two springs is the amplitude of the fatigue load, and the pre-pressure of the springs is reserved; fixing two ends of the linear material by using a winding clamp, and loading to an average value of a fatigue load; mounting the assembled long-rod bolt, spring and sample upper clamp on the sample, and connecting with a fatigue machine connecting sheet; loading to the maximum value of the fatigue load; a sample lower clamp is hung on the sample; the distance between the linear material and the fatigue machine stand column is measured, a tensioner and a U-shaped bolt baffle assembly are installed, and it is ensured that the distance between the linear material and the fatigue machine stand column is not changed; and unloading until the wire rod is bent, clearing the load, and then starting a fatigue test. According to the utility model, effective tension-tension fatigue test can be carried out on the linear material, and accurate wire fatigue performance data can be obtained.

The present application relates to the technical field of high-temperature structural component fatigue strength design and life assessment, and particularly relates to a low-cycle multi-axial fatigue life prediction method based on powder high-temperature alloy damage mechanism. The method comprises: for the dangerous point of the component under non-isothermal multi-axial cyclic loading, calculating pure fatigue damage, pure creep damage and fatigue-creep interaction damage caused by a single load cycle; accumulating the pure fatigue damage, the pure creep damage and the fatigue-creep interaction damage to obtain the total damage of the single load cycle; taking the inverse of the total damage to predict the total failure life of the component under non-isothermal multi-axial cyclic loading. The method of the present application realizes effective prediction of the low-cycle multi-axial fatigue life of the powder high-temperature alloy component by accurately decomposing the damage of the dangerous point under non-isothermal multi-axial cyclic loading, can more truly reflect the comprehensive prediction model of the failure physics of the powder high-temperature alloy under multi-axial thermal mechanical loading, and improves the accuracy and reliability of the life assessment.

The utility model relates to the technical field of spine surgery nursing, in particular to a rehabilitation exercise device which comprises a nursing bed, a shell, two round rods, a sliding plate, a rolling shaft, a plurality of rubber wheels, a stepping motor, a rotating frame, a connecting rod, a fixing column, two sets of buffering units, an auxiliary unit and a protection unit. A controller is clicked to start a stepping motor, so that the stepping motor drives a rotating frame to rotate, a connecting rod is used for pulling a fixing column to move leftwards, at the moment, a buffering unit pulls a rolling shaft to move, a rubber wheel rolls on the back of a patient, the rotating frame rotates in a shaft mode, a sliding plate is pulled to move back and forth on a round rod, and rehabilitation treatment is conducted on the patient through repeated operation. The auxiliary unit is used for supporting the patient to get on and off the nursing bed, so that the fatigue strength of workers is reduced, and the rehabilitation quality and efficiency can be effectively improved.

The invention provides a method for calculating the fatigue limit of an aluminum alloy by utilizing defects and yield strength, which comprises the following steps: S1, obtaining the yield strength of the aluminum alloy by utilizing a tensile test; s2, a fatigue test is utilized, a large load is loaded, the sample is broken within 2 hours, and a fatigue fracture is obtained; s3, observing a fatigue crack source, and measuring the defect area and the like of the crack source; s4, according to the results of the steps S1 and S3, calculating the fatigue limit by using a mathematical relationship between the yield strength, the defect area and the like and the fatigue limit to obtain a first fatigue strength value; s5, repeating the steps S2, S3 and S4 to obtain a second fatigue strength value; repeating the steps S2, S3 and S4 again to obtain a third fatigue strength value; and by parity of reasoning, after three or more fatigue strength values are obtained, an average value, namely the fatigue limit, is obtained. The method has the beneficial effects that the defect and the yield strength are comprehensively considered, the accuracy of the calculated fatigue limit is higher, and time, manpower and material resources are saved.

This invention provides a novel vibration fatigue testing method for gas turbine blades. Addressing the problems of large specimen wear, long testing time, and limited results associated with traditional step-and-step stress loading methods for obtaining blade fatigue limits, this invention excites blade resonance on an electromagnetic vibration table using novel step-and-step stress loading techniques on identical blade specimens. While retaining the step-and-step matching standard, when limited test data cannot meet the matching requirements, a stress "concession" method is rationally applied based on the turbine blade structure and fatigue strength level to eliminate test data with significant stress deviations, thereby obtaining the median fatigue strength of blades from the same batch. This invention makes stress matching faster and more flexible, requiring only 2-3 stress levels to achieve a test fitting result with a confidence level of over 95%, demonstrating high accuracy. This method is applicable to fatigue limit tests of all gas turbine blades.

The application discloses a testing device integrating the testing of the elasticity of a hair piece and the fatigue strength of a shuttlecock, and relates to the technical field of the fatigue strength testing of the shuttlecock. The testing device comprises a machine table, a guide rail horizontally arranged on the top surface of the machine table, a mounting seat fixed on the top surface of a sliding block, a pressure sensor fixed on the right end surface of the mounting seat, a mounting plate fixed on the right end surface of the pressure sensor, a force transmission rod fixed on the right end surface of the mounting plate, and a hitting block fixed on the right end of the force transmission rod. A tooling mechanism for fixing the hair piece and the shuttlecock is further arranged on the machine table. The application has the advantages that the elasticity of the hair piece can be tested, and the fatigue strength testing efficiency of the shuttlecock is improved.

The invention relates to the technical field of mechanical structure fatigue testing, and discloses a copper valve clack fatigue strength testing method based on an intelligent sensor. Pressure sensors are arranged at an inlet and an outlet of the valve, pressure in the whole opening and closing process is continuously collected to form an original time sequence, and pulsating pressure is obtained by subtracting the average pressure in the whole time period; an overlapping analysis window is constructed based on pulsating pressure, frequency energy of each window is solved by using a preset frequency mapping function and weighted to obtain a frequency spectrum gravity center and statistical characteristics of the frequency spectrum gravity center changing along with the window, and accordingly, a single-side fatigue damage index of each sensor is constructed and a most unfavorable measuring point is selected as an overall damage index. And combining the pulsating pressure root-mean-square value to obtain a fatigue strength evaluation value. Through the process, pressure fluctuation of the valve under all working conditions is reflected, static bias and noise influences are restrained, fatigue related frequency energy is highlighted, and online quantitative evaluation and early warning of the fatigue evolution degree of the valve clack are achieved.

The present invention discloses a method for predicting the fatigue strength of metal materials by hardness, belonging to the field of materials science and engineering application technology. The method first establishes a fitting relationship between the hardness value and the fatigue strength coefficient and fatigue strength index based on data such as the material's hardness and fatigue curve, and then establishes a fatigue life prediction formula for the material based on the Basquin formula. The fatigue strength of the material can be obtained by substituting the number of cycles of fatigue test cycle stop (or the number of cycles of the S-N curve platform). This method effectively reduces the amount of experiments required to predict the fatigue strength of the material, greatly saving manpower and financial costs. It has the characteristics of simplicity, speed and accuracy, and can be widely applied to metal materials with different hardness obtained by hot working.

This invention discloses a system fatigue reliability prediction method for large aerospace planetary mechanisms. The steps are as follows: The fatigue load history of gear teeth under the coupled action of the system's global elastic behavior is calculated using the hierarchical finite element method to obtain load information; the probabilistic fatigue strength curve of the gear teeth is fitted based on gear low-cycle fatigue testing and the minimum order statistic conversion method; the load information and the probabilistic fatigue strength of the gear teeth are input into a reliability prediction model to obtain a system fatigue reliability prediction model that can consider the influence of system structural elements, establishing a mapping path from key structural elements of large aerospace planetary mechanisms to system reliability indicators. This invention leverages the stiffness potential of core structural elements to balance the contradiction between reliability and lightweight requirements in large aerospace planetary equipment; detailed tooth root stress calculations are not required in the system-level model; and a gear tooth probabilistic fatigue strength conversion method is proposed, thereby saving significant simulation and testing costs.

The invention belongs to the field of fatigue strength testing of metal materials, and particularly relates to a clamping device suitable for tension-tension fatigue performance testing of a linear material and a testing method. A fatigue machine connecting piece is fixed to a fatigue machine, and the load is reset; the long-rod bolt, the springs and the sample upper clamp are assembled, so that the resultant force of the pre-pressure of the two springs is the amplitude of the fatigue load, and the pre-pressure of the springs is reserved; fixing two ends of the linear material by using a winding clamp, and loading to an average value of a fatigue load; mounting the assembled long-rod bolt, spring and sample upper clamp on the sample, and connecting with a fatigue machine connecting sheet; loading to the maximum value of the fatigue load; a sample lower clamp is hung on the sample; the distance between the linear material and the fatigue machine stand column is measured, a tensioner and a U-shaped bolt baffle assembly are installed, and it is ensured that the distance between the linear material and the fatigue machine stand column is not changed; and unloading until the wire rod is bent, clearing the load, and then starting a fatigue test. According to the invention, effective tension-tension fatigue test can be carried out on the linear material, and accurate wire fatigue performance data can be obtained.

The invention provides a gas turbine compressor blade service life evaluation method based on high-cycle fatigue characteristics, and aims to solve the problem that fatigue tests under pure simulation and laboratory conditions cannot be effectively combined to meet the requirement of gas turbine blade type core component service life evaluation. According to the method, the strength condition and the vibration condition of the blade are determined through finite element analysis, then the stable attenuation law of the fatigue strength of the blade is obtained by actually measuring the vibration stress and the fatigue limit values of the blade in different use time periods, and the service life of the gas turbine compressor blade is comprehensively evaluated by taking the high-cycle vibration fatigue reserve as the standard. The method is not limited to a ship gas turbine compressor, is also suitable for effective evaluation of the service life of the moving blades of an industrial gas turbine and an aero-engine compressor, and can provide a fatigue reliability design direction for a new model.

The utility model discloses a device for detecting fatigue strength of torsion bar springs of chassis of various vehicles. The device structurally comprises an electrified positioning block, a parallel base, a protection plate, an electric control plate, a first detection body, a second detection body and a sliding rail, according to the utility model, the transverse slide rail is arranged on the parallel base as a basis, and the slide block at the lower end of the solid block of the second detection body slides in the slide rail, so that the distance between the detection rotating shaft in the convex block at the upper end of the solid block and the detection rotating shaft of the first detection body can be changed, and therefore, the torsion bar spring detection device can be matched with various torsion bar springs with different lengths; the torsion bar spring detection device can effectively adapt to torsion bar springs with different lengths for detection, a large number of driving parts can be saved for use through manual pushing of the control push block on the solid block, and the effects of saving cost and improving the practicability of the whole detection device can be achieved.

The utility model discloses a kind of anti-fatigue structures of shock-absorbing shaft, it is related to shock-absorbing shaft technical field, including inner shaft, outer sleeve and anti-fatigue component, the lower end and upper end of the inner shaft are respectively fixed with fixed lower plate, fixed upper plate, the outer side of the inner shaft is provided with anti-fatigue component, and anti-fatigue component includes bellow, shock-absorbing spring, spring washer and airbag layer, the outer side of the inner shaft is attached to bellow, and the outside of bellow is provided with shock-absorbing spring, and the upper and lower ends of shock-absorbing spring are both fixed with spring washer, the spring washer top end of upper side is fixedly connected with fixed upper plate, the spring washer bottom surface of lower side is installed with airbag layer, and the airbag layer is annular structure and located the outer side of inner shaft.The anti-fatigue structure of shock-absorbing shaft, bellow of inner shaft outer side can disperse acting force in the process of axial shock-absorbing, to improve the fatigue strength of inner shaft, and shock-absorbing spring cooperates airbag layer can buffer shock-absorbing, dispersion and absorption energy generated by road surface.

The invention provides a fatigue strength simulation method and device and a readable storage medium. An electronic device establishes a finite element model for a planet carrier with the fatigue strength to be simulated, and the finite element model is used for outputting a finite element simulation file set of the planet carrier under the unit working condition. Then, the electronic equipment generates an input file set of simulation software according to the time sequence load file of the planet carrier and the finite element simulation file set; finally, the input file set is processed through simulation software to obtain a simulation result of the fatigue strength of the planet carrier, the automation degree is high, the accuracy is high, the fatigue strength simulation efficiency is improved to a great extent, and the labor cost is saved.

The present invention provides a vibration fatigue resistance design method for a helicopter secondary load-bearing structure, the method comprising: applying a vertical unit acceleration excitation to an installation platform to obtain a stress frequency response curve of a secondary load-bearing structure member; based on the frequency response curve, determining a first resonance main peak and a first frequency value corresponding to the first resonance main peak, and determining a dangerous part based on the first frequency value; based on an S-N curve of a structural material at the dangerous part, determining a fatigue limit value of the structural material; based on the fatigue limit value and a helicopter vibration environment spectrum, obtaining a maximum allowable transfer function; the present invention proposes a vibration fatigue resistance design process and method for a helicopter secondary load-bearing structure, analyzing the vibration fatigue strength of the secondary load-bearing member under a vibration environment and optimizing the structure to ensure that the structure meets strength and use requirements.

The application relates to the technical field of machine learning and intelligent manufacturing, in particular to a material fatigue strength prediction method, equipment and a storage medium. The method comprises the following steps: acquiring the load level of each sample of a measured material; determining a global smoothing parameter with a Gaussian kernel function as a reference based on the load level of each sample, and determining the smoothing parameter of each kernel function based on the global smoothing parameter; estimating the probability density function of the fatigue strength of the measured material based on each kernel function and the smoothing parameter of each kernel function; and calculating an expected value and a standard deviation based on the estimated probability density function, and taking the expected value and the standard deviation as the estimated value and the estimated standard deviation of the fatigue strength of the measured material respectively. The method of the application effectively improves the accuracy and reliability of the estimated average value and the estimated standard deviation of the fatigue strength.

The invention relates to a high-reliability gear fatigue limit rapid test method based on a reliability conversion coefficient, and the method specifically comprises the steps: carrying out a gear fatigue strength lifting method test, and obtaining the reliability conversion coefficient based on a mathematical statistical method; carrying out a Locati method fatigue test to obtain a fatigue test point; processing a test result of the Locati method based on a reference fatigue S-N curve, and obtaining a gear fatigue limit under 50% reliability; and according to the gear fatigue limit under the reliability of 50%, evaluating the gear fatigue limit under the high reliability by applying the reliability conversion coefficient. The problems of large test sample size, high cost and long test period required for obtaining the high-reliability gear fatigue limit are solved, and a high-precision evaluation result can be kept while the test quantity is reduced; the method can be conveniently applied to engineering practice, and efficient method support is provided for gear anti-fatigue and high-power-density design.