CN114611364A - Fretting fatigue life prediction method considering surface hardness and plastic strain - Google Patents

Fretting fatigue life prediction method considering surface hardness and plastic strain Download PDF

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CN114611364A
CN114611364A CN202210288410.5A CN202210288410A CN114611364A CN 114611364 A CN114611364 A CN 114611364A CN 202210288410 A CN202210288410 A CN 202210288410A CN 114611364 A CN114611364 A CN 114611364A
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张宏建
秦钰岭
崔海涛
温卫东
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Abstract

The invention discloses a fretting fatigue life prediction method considering surface hardness and plastic strain, which comprises the following steps of (1) establishing a finite element model of a prediction component, inputting material parameters, defining damage parameters of each unit in the finite element model, and assuming that all units are not damaged in an initial state and the initial value of the damage parameters is 0; (2) establishing a Chaboche elastoplasticity damage constitutive model in computer software, and representing the relationship between the accumulated equivalent plastic strain increment and the stress strain; (3) bringing in the surface hardness related factor, and calculating the damage parameter based on the Chaboche NLCD life model; (4) and calculating the damage parameter of the nonlinear accumulated damage model based on the plastic strain increment correlation by including the surface hardness correlation factor. The method can effectively predict the high-temperature fretting fatigue life under the condition of dissimilar material contact, and can predict the fretting fatigue life for different types of structural contact pieces.

Description

Fretting fatigue life prediction method considering surface hardness and plastic strain
Technical Field
The invention belongs to the field of fretting fatigue life prediction simulation, relates to a fretting fatigue life prediction method considering surface hardness and plastic strain, and particularly relates to a high-temperature fretting fatigue life prediction model considering material surface hardness based on continuous medium damage, and an establishment method and an application method thereof.
Background
Fretting fatigue occurs between two surfaces which have relative motion with extremely small amplitude, the magnitude of displacement amplitude is generally only micron-sized, the fretting fatigue is a main damage mode of a connecting structure, and the fretting fatigue is widely existed in two or more mutually matched components in an aircraft engine, such as a joggle joint structure, an end tooth connecting structure and the like. The occurrence of fretting can cause wear of the contact surfaces of the materials, which in turn causes structural loosening, resulting in increased power loss during engine operation, with a series of problems such as noise, and, in addition, the more serious consequence is structural failure due to fretting fatigue. Persistent micromotion can also cause other problems such as corrosion, damage, etc., known as "industrial cancer".
The aircraft engine is called as the heart of an aircraft, wherein a turbine disc and turbine blades are one of the most critical components in the aircraft engine, the relevant research on the prediction of the fretting fatigue life of the joggle joint structure can provide a foundation for the research on the reliability of the operation of the turbine structure of the aircraft engine under the harsh working condition, and the method has important significance on the material selection and the structural design of high-temperature components such as the turbine disc, the blades and the like.
Damage is a non-independent physical property that represents a degradation of the material itself in terms of mechanical properties. Macroscopically, it can be considered that in the process of damage, parameters such as elastic coefficient, yield stress, density and the like of the material are degraded, and then the parameters can be selected as variables to measure the damage. On the microscopic scale, parameters such as the number and volume of defects such as micro cracks and cavities in the material can be used as damage parameters. In continuous media mechanics, the damage variable D reflects the irreversible process of the material structure, and the damage variable can affect many other parameters of the material, such as physics, mechanics, etc.
Disclosure of Invention
The invention provides a fretting fatigue life prediction method considering surface hardness and plastic strain, and the fretting fatigue life prediction method considering material surface hardness and plastic strain is used for effectively predicting the fretting fatigue life under the contact of dissimilar materials.
In order to achieve the above object, according to one aspect of the present invention, the present invention provides the following technical solutions:
a fretting fatigue life prediction method considering surface hardness and plastic strain comprises the following steps,
(1) establishing a finite element model of the predicted part, inputting material parameters, defining damage parameters of each unit in the finite element model, and assuming that all units are not damaged in an initial state and the initial values of the damage parameters are 0;
(2) establishing a Chaboche elastoplastic damage constitutive model in computer software, and representing the relationship between the accumulated equivalent plastic strain increment and the stress strain;
(3) bringing in the surface hardness related factor, and calculating the damage parameter based on the Chaboche NLCD life model;
(4) the method comprises the steps of incorporating surface hardness correlation factors, and calculating damage parameters of a nonlinear accumulated damage model based on plastic strain increment correlation;
(5) and (3) integrating the calculation results of the step (3) and the step (4) to obtain the damage parameters of the unit, when the sum of the damage parameters of a certain unit reaches a specified value, considering that the unit is damaged and failed, no force is transmitted, and the rigidity of the unit is reduced, if the crack formed by the damaged and failed unit does not reach the specified length at the moment, returning to the step (3) for continuous calculation, if the crack formed by the damaged and failed unit reaches the specified length, considering that the part has fatigue damage, stopping calculating and recording the total number of cycles, wherein the total number of cycles is the service life value.
The invention is further configured that, in the step (2), the relationship between the cumulative equivalent plastic strain increment and the stress strain is characterized, specifically,
in the Chaboche elastoplasticity damage constitutive model in the step (2), the total strain epsilon under the assumption of small deformationijCan be expressed as elastic strain epsilone ijAnd plastic strain epsilonp ijThe sum, i.e.,
Figure BDA0003559204150000021
for elastic strain epsilone ijThe injury mechanics is expressed as follows,
Figure BDA0003559204150000022
wherein E is the elastic modulus, v is the Poisson's ratio, σijIs Cauchi stress, σkkδijIs subscript operation, D is damage parameter,
for plastic strain εp ijThe expression is as follows,
Figure BDA0003559204150000023
in the formula (I), the compound is shown in the specification,
Figure BDA0003559204150000024
for the increase in plastic strain, λ is the plasticity factor, F is the parametric Mises yield function, the expression for F is as follows,
Figure BDA0003559204150000025
in the formula, sijIs the stress offset, αijFor back stress, Y is the yield face radius, which can be considered the initial yield stress,
the combined type (3) and (4) can be obtained,
Figure BDA0003559204150000026
wherein eq is an equivalent angle scale,
under the condition of continuity, the plasticity factor lambda has the following expression,
Figure BDA0003559204150000027
wherein Δ p is the cumulative equivalent plastic strain increase,
Figure BDA0003559204150000028
in order to be a plastic strain rate, the strain rate,
for back stress alphaijIs provided with
Figure BDA0003559204150000031
Figure BDA0003559204150000032
In the formula, ck、γkAre all the constant of the material, and the material,
Figure BDA0003559204150000033
in order to be subjected to a plastic strain,
Figure BDA0003559204150000034
is the back stress at the kth set of strengthening components.
The invention is further set that in the step (3), the damage parameter calculation based on the Chaboche NLCD life model is carried out, specifically,
firstly, the damage evolution equation of the Chaboche nonlinear accumulated damage fatigue is as follows,
Figure BDA0003559204150000035
wherein N represents the number of cycles, and the form of alpha is shown as the following formula,
Figure BDA0003559204150000036
d is the damage variable, σ is the stress, σbIs the strength limit of the material, σmaxFor the maximum stress per cycle the stress is,
Figure BDA00035592041500000312
for mean stress, M0Beta is a coefficient depending on the material and is obtained by uniaxial fatigue test fitting; sigmal0Is the fatigue limit under reverse stress conditions,
Figure BDA00035592041500000311
fatigue limit under non-zero mean stress, a is initial contact half width;
redefining parameters in the formula (9) under multiaxial fatigue; average stress
Figure BDA00035592041500000313
Replacement by mean hydrostatic stress σH，meaCalculating to obtain a multi-axial fatigue limit
Figure BDA0003559204150000037
Figure BDA0003559204150000038
The equivalent stress amplitude under the multi-axial fatigue load is AIIThe formula is as follows:
Figure BDA0003559204150000039
σ′ij，maxis the maximum value of each stress deviation in the cycle, sigma'ij，minIs the minimum value of the stress offsets in the cycle, σ1、σ2、σ3Is the principal stress amplitude;
the alpha after the redefinition is that,
Figure BDA00035592041500000310
σlin order to be the fatigue limit,
the mean hydrostatic stress σH，meanThe calculation formula of (a) is as follows:
Figure BDA0003559204150000041
wherein σ11，σ22，σ33Is three principal stresses, oH，maxMaximum hydrostatic stress, σH，minIs the minimum hydrostatic stress;
thirdly, introducing a damage accumulation rate factor considering hardness correlation
Figure BDA0003559204150000042
The formula (9) is corrected,
Figure BDA0003559204150000043
the expression is as follows:
Figure BDA0003559204150000044
wherein T is the operating temperature T0At room temperature. t is a temperature-related parameter, eta is a hardness-related parameter, and is obtained by fitting a fretting fatigue test, H1In order to inching the surface hardness of the pad material in a single-chuck inching fatigue test, the surface hardness of the tenon material in a tenon joint structure is represented by H2In order to test the surface hardness of the material of the part in a single-chuck type micro-dynamic fatigue test, the surface hardness of the material of the mortise in a tenon joint structure is represented by Tm1In the single-chuck type micromotion fatigue test, the material is a micromotion cushion, and the melting point temperature T of the tenon material in the tenon joint structurem2In single-chuck type micro-dynamic fatigue testThe test piece represents the melting point temperature of the mortise material in the mortise joint structure,
synthesizing formulas (9) to (14), and obtaining a damage parameter expression of a Chaboche NLCD life model as
Figure BDA0003559204150000045
D in formula 15 is represented by DeAt this time DeNamely, the damage parameter of the Chaboche NLCD life model represents the influence of stress on accumulated damage.
The invention is further configured that, in the step (4), the damage parameter calculation based on the plastic strain increment-related nonlinear accumulated damage model is carried out, specifically,
d of damage parameters in the plastic strain increment-related nonlinear accumulated damage model obtained in the step (2)pThe expression of (a) is as follows,
Figure BDA0003559204150000046
wherein E is elastic modulus, S and m are material constants, and are obtained by calculation from strain fatigue parameter dataHThe pressure is the hydrostatic pressure, and the pressure is the hydrostatic pressure,
Figure BDA0003559204150000047
is the maximum value of damage equivalent stress in one cycle, damage equivalent stress sigma*The formula for calculating (a) is as follows,
Figure BDA0003559204150000048
introduction of a factor that considers the hardness-related rate of accumulation of damage
Figure BDA0003559204150000051
The formula (16) is corrected so that,
Figure BDA0003559204150000052
is expressed by the formula (14), corrected DpThe expression is as follows:
Figure BDA0003559204150000053
the invention is further configured that, in the step (5), the calculation results of the step (3) and the step (4) are integrated to obtain the damage parameter, specifically,
definitions D and Dp、DeThe relational expression of (a) is:
D＝max{De，Dp} (19)
namely, D is considered to be DeAnd DpMaximum value of (2).
The invention is further set that when the damage parameter of a certain unit reaches 0.92, the unit is considered to be damaged and invalid, no force is transmitted, the rigidity of the unit is reduced, and rigidity correction is carried out; when the crack formed by the failed cell reached 200 μm, the part was considered to have failed in fatigue, the calculation was stopped and the total number of cycles was recorded.
Compared with the prior art, the invention has the advantages that: 1. the method can effectively predict the high-temperature fretting fatigue life under the condition of contact of dissimilar materials, and has important engineering significance; 2. the method can predict the fretting fatigue life aiming at different types of structural contact elements, such as a tenon connection structure of the gas compressor and the turbine disc, an arc end tooth structure for connecting the wheel disc and a sleeve tooth structure for connecting the wheel disc and a transmission shaft, and has important engineering significance; 3. the method can predict the crack initiation and early expansion of the structural contact under the contact pair of dissimilar materials, and has important engineering significance.
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FIG. 1 is a flow chart of the use of the present invention.
Detailed Description
The invention is further described with reference to the accompanying drawings.
The invention provides a fretting fatigue life prediction method considering surface hardness and plastic strain, and the model and the application method can effectively predict the high-temperature fretting fatigue life, crack initiation and early propagation under the condition of dissimilar material contact, and have important engineering significance. The method comprises the following specific steps:
1): a finite element model of a predicted part is established in ABAQUS software, material parameters are input, and damage parameters D of all units in the finite element model in an initial state are defined to be 0.
2): a Chaboche elastoplasticity damage constitutive model is established in ABAQUS software. And (4) characterizing the relationship of the cumulative equivalent plastic strain increment and the stress strain. Total strain epsilon of the constitutive model under the assumption of small deformationijCan be expressed as elastic strain epsilone ijAnd plastic strain epsilonp ijAnd (c) the sum, i.e.:
Figure BDA0003559204150000061
for elastic strain
Figure BDA0003559204150000062
The following expressions are used in the mechanics of injury:
Figure BDA0003559204150000063
wherein E is the elastic modulus, v is the Poisson's ratio, σijIs Cauchi stress, σkkδijIn order to calculate the subscript,
for plastic strain
Figure BDA0003559204150000064
The following expression is given:
Figure BDA0003559204150000065
wherein the content of the first and second substances,
Figure BDA0003559204150000066
to be plasticThe delta, λ is the plasticity factor and F is the mies yield function of the parameter. The expression for F is as follows:
Figure BDA0003559204150000067
wherein s isijIs the stress offset, αijFor back stress, Y is the yield face radius and can be considered the initial yield stress.
The combined type (3) and (4) can obtain:
Figure BDA0003559204150000068
wherein eq is an equivalent angle scale,
under continuous conditions, the plasticity factor λ mentioned above has the following expression:
Figure BDA0003559204150000069
wherein Δ p is the cumulative equivalent plastic strain increase,
Figure BDA00035592041500000610
is the plastic strain rate.
Back stress alpha to the Chaboche damage constitutive modelijIs provided with
Figure BDA00035592041500000611
Figure BDA00035592041500000612
In the formula, ck、γkAre all the constant of the material, and the material,
Figure BDA00035592041500000613
in order to be subjected to a plastic strain,
Figure BDA00035592041500000614
is the back stress at the kth set of strengthening components. This constitutive model is used in this calculation to describe the quantitative degree of influence of D on the material property degradation.
3): the calculation of the damage parameters first requires the use of an NLCD model. The model considers the maximum stress sigma in the evolution process and the circulation of the damage parameter DmaxAnd mean stress σmIn this regard, the evolutionary expression is as follows:
Figure BDA0003559204150000071
integration of equation (9) yields:
Figure BDA0003559204150000072
equation (9) is redefined accordingly for the multiaxial fatigue requirement, as shown in equation (11):
Figure BDA0003559204150000073
wherein, N represents the number of cycles,
formula (11) ismaxAnd σmReplacement by equivalent stress amplitude A under multiaxial fatigueIIAnd multiaxial fatigue limit AII *. Redefining alpha as AIIAnd AII *Of a correlation function, i.e.
Figure BDA0003559204150000074
σlIn order to be the fatigue limit,
multiaxial fatigue limit AII *With the mean hydrostatic stress σH，meanIn relation thereto, the expression is:
Figure BDA0003559204150000075
the average hydrostatic stress is the maximum hydrostatic stress sigma in the circulation processH，maxWith minimum hydrostatic stress sigmaH，minIs expressed as:
Figure BDA0003559204150000076
in the formula, σ11、σ22And σ33Three principal stresses. Equivalent stress amplitude A under multiaxial fatigueIIThe expression of (a) is as follows:
Figure BDA0003559204150000077
in the formula, σij，maxAnd σij，minRespectively the maximum value and the minimum value of each stress offset in the circulation; sigma1、σ2And σ3Is the principal stress amplitude.
Introduction of a factor that considers the hardness-related rate of accumulation of damage
Figure BDA0003559204150000078
The formula (11) is corrected,
Figure BDA0003559204150000079
the expression is as follows:
Figure BDA00035592041500000710
t is the working condition temperature T0Room temperature, t is a temperature-related parameter, η is a hardness-related parameter, and can be obtained by fitting fretting fatigue test data, H1In order to inching the surface hardness of the pad material in a single-chuck inching fatigue test, the surface hardness of the tenon material in a tenon joint structure is represented by H2For testing a workpiece in a single-chuck type micro-dynamic fatigue testMaterial surface hardness, representing the tongue-and-groove material surface hardness in a tongue-and-groove structure, Tm1In the single-chuck type micromotion fatigue test, the material is a micromotion cushion, and the melting point temperature T of the tenon material in the tenon joint structurem2The test piece is used in a single-chuck type micro-dynamic fatigue test, and represents the melting point temperature of a tongue-and-groove material in a tenon joint structure.
Integrating the formula (11) to the formula (16), and obtaining an expression of the damage parameter D in the model as
Figure BDA0003559204150000081
In the formula, D is represented as DeAt this time DeNamely, the damage parameter of the Chaboche NLCD life model represents the influence of stress on accumulated damage.
4): in order to perfect the calculation of the accumulated damage parameter D, the D of the damage parameter in the nonlinear accumulated damage model which is obtained by the step (2) and is related to the plastic strain incrementpThe expression of (a) is:
Figure BDA0003559204150000082
wherein E is the elastic modulus, S and m are the material constants, obtained from the strain fatigue parameter data in the materials handbook, σHThe pressure is the hydrostatic pressure, and the pressure is the hydrostatic pressure,
Figure BDA0003559204150000083
is the maximum value of damage equivalent stress in one cycle, damage equivalent stress sigma*The calculation formula of (2) is as follows:
Figure BDA0003559204150000084
introduction of a factor that considers the hardness-related rate of accumulation of damage
Figure BDA0003559204150000085
The formula (18) is corrected so that,
Figure BDA0003559204150000086
is represented by formula (16). Corrected DpThe expression is as follows:
Figure BDA0003559204150000087
5): in the calculation of the damage parameter D, in order to save calculation time on the basis of ensuring calculation accuracy, 1000 actual cycles are taken as one calculation period, and the damage parameter D in 1000 actual cycles is regarded as linearly increasing, that is, the actual 1000 cycles are considered to be completed in one load step.
The calculation method of the accumulated damage parameter D is as follows (21):
D＝max{De，Dp} (21)
i.e. D is DeAnd DpMaximum value of (2). When the sum of the damage parameters of a certain unit reaches 0.92, the unit is considered to be failed, the force transmission capacity is no longer possessed, and the rigidity of the unit is corrected. When the crack constituted by the failed unit reached 200 μm, i.e., 0.2mm, the part was considered to have undergone crack initiation and early propagation. And recording the load step number at the moment, multiplying the load step number by 1000 to obtain the current cycle number, wherein the cycle number is the service life value, and stopping the calculation.
The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above-mentioned embodiments, and all technical solutions belonging to the idea of the present invention belong to the protection scope of the present invention. It should be noted that modifications and embellishments within the scope of the invention may be made by those skilled in the art without departing from the principle of the invention.

Claims (6)

1. A fretting fatigue life prediction method considering surface hardness and plastic strain is characterized by comprising the following specific operation steps of:
(1) establishing a finite element model of the predicted part, inputting material parameters, defining damage parameters of each unit in the finite element model, and assuming that all units are not damaged in an initial state and the initial values of the damage parameters are 0;
(2) establishing a Chaboche elastoplasticity damage constitutive model in computer software, and representing the relationship between the accumulated equivalent plastic strain increment and the stress strain;
(3) bringing in the surface hardness related factor, and calculating the damage parameter based on the Chaboche NLCD life model;
(4) the method comprises the following steps of (1) incorporating surface hardness related factors, and calculating damage parameters of a nonlinear accumulated damage model based on plastic strain increment correlation;
(5) and (3) integrating the calculation results of the step (3) and the step (4) to obtain the damage parameters of the unit, when the sum of the damage parameters of a certain unit reaches a specified value, considering that the unit is damaged and failed, no force is transmitted, and the rigidity of the unit is reduced, if the crack formed by the damaged and failed unit does not reach the specified length at the moment, returning to the step (3) for continuous calculation, if the crack formed by the damaged and failed unit reaches the specified length, considering that the part has fatigue damage, stopping calculating and recording the total number of cycles, wherein the total number of cycles is the service life value.
2. The fretting fatigue life prediction method considering surface hardness and plastic strain according to claim 1, wherein: in the step (2), the relationship between the cumulative equivalent plastic strain increment and the stress strain is characterized, specifically,
in the Chaboche elastoplasticity damage constitutive model in the step (2), the total strain epsilon under the assumption of small deformationijCan be expressed as elastic strain epsilone ijAnd plastic strain
Figure FDA0003559204140000011
The sum, i.e.,
Figure FDA0003559204140000012
for elastic strain epsilone ijThe injury mechanics is expressed as follows,
Figure FDA0003559204140000013
wherein E is the elastic modulus, v is the Poisson's ratio, σijIs Cauchi stress, σkkδijIs subscript operation, D is damage parameter,
for plastic strain
Figure FDA0003559204140000014
The expression is shown as follows,
Figure FDA0003559204140000015
in the formula (I), the compound is shown in the specification,
Figure FDA0003559204140000016
for the increase in plastic strain, λ is the plasticity factor, F is the parametric Mises yield function, the expression for F is as follows,
Figure FDA0003559204140000017
in the formula, sijIs the stress offset, αijFor back stress, Y is the yield face radius, which can be considered the initial yield stress,
the combined type (3) and (4) can be obtained,
Figure FDA0003559204140000021
wherein eq is an equivalent angle scale,
under the condition of continuity, the plasticity factor lambda has the following expression,
Figure FDA0003559204140000022
wherein Δ p is the cumulative equivalent plastic strain increase,
Figure FDA0003559204140000023
in order to be able to measure the plastic strain rate,
for back stress alphaijIs provided with
Figure FDA0003559204140000024
Figure FDA0003559204140000025
In the formula, ck、γkAre all the constant of the material, and the material,
Figure FDA0003559204140000026
in order to be subjected to a plastic strain,
Figure FDA0003559204140000027
the back stress at the kth set of strengthening components.
3. The fretting fatigue life prediction method considering surface hardness and plastic strain according to claim 2, wherein: in the step (3), the damage parameter calculation based on the Chaboche NLCD life model is carried out, specifically,
firstly, the damage evolution equation of the Chaboche nonlinear accumulated damage fatigue is as follows,
Figure FDA0003559204140000028
wherein N represents the number of cycles, and the form of alpha is shown as the following formula,
Figure FDA0003559204140000029
d is the damage variable, σ is the stress, σbIs the strength limit of the material, σmaxFor the maximum stress per cycle the stress is,
Figure FDA00035592041400000210
for mean stress, M0Beta is a coefficient which depends on the material and is obtained by uniaxial fatigue test fitting; sigmal0Is the fatigue limit under conditions of reverse stress,
Figure FDA00035592041400000211
fatigue limit under non-zero mean stress, a is initial contact half width;
redefining parameters in the formula (9) under multi-axial fatigue; average stress
Figure FDA00035592041400000212
Replacement by mean hydrostatic stress σH，meanCalculating to obtain a multi-axial fatigue limit
Figure FDA00035592041400000213
Figure FDA00035592041400000214
The equivalent stress amplitude under the multi-axial fatigue load is AIIThe formula is as follows:
Figure FDA0003559204140000031
σ′ij，maxis the maximum value of each stress offset in the cycle, sigma'ij，minIs the minimum value of the stress offsets in the cycle, σ1、σ2、σ3Is the principal stress amplitude;
the alpha after the redefinition is that,
Figure FDA0003559204140000032
σlin order to be the fatigue limit,
the mean hydrostatic stress σH，meanThe calculation formula of (a) is as follows:
Figure FDA0003559204140000033
wherein σ11，σ22，σ33Is three principal stresses, σH，maxMaximum hydrostatic stress, σH，minIs the minimum hydrostatic stress;
thirdly, introducing a damage accumulation rate factor considering hardness correlation
Figure FDA0003559204140000034
The formula (9) is corrected,
Figure FDA0003559204140000035
the expression is as follows:
Figure FDA0003559204140000036
wherein T is the operating temperature T0Is room temperature, t is a temperature related parameter, eta is a hardness related parameter, and is obtained by fitting a fretting fatigue test, H1In order to inching the surface hardness of the pad material in a single-chuck inching fatigue test, the surface hardness of the tenon material in a tenon joint structure is represented by H2In order to test the surface hardness of the material of the part in a single-jaw-type micro-dynamic fatigue test, the surface hardness of the material of the tongue-and-groove in a joggled joint structure is represented by Tm1In the single-chuck type micromotion fatigue test, the material is a micromotion cushion, and the melting point temperature T of the tenon material in the tenon joint structurem2In the single-chuck type micro-dynamic fatigue test, the test piece is a joggle jointThe structure represents the melting point temperature of the mortise material,
synthesizing formulas (9) to (14), and obtaining a damage parameter expression of a Chaboche NLCD life model as
Figure FDA0003559204140000037
D in formula 15 is represented by DeAt this time DeNamely, the damage parameter of the Chaboche NLCD life model represents the influence of stress on accumulated damage.
4. The fretting fatigue life prediction method considering surface hardness and plastic strain according to claim 3, wherein: in the step (4), the damage parameter calculation based on the plastic strain increment-related nonlinear accumulated damage model is performed, specifically,
d of damage parameters in the plastic strain increment-related nonlinear accumulated damage model obtained in the step (2)pThe expression of (a) is as follows,
Figure FDA0003559204140000041
wherein E is elastic modulus, S and m are material constants, and are obtained by calculation from strain fatigue parameter dataHThe pressure is the hydrostatic pressure, and the pressure is the hydrostatic pressure,
Figure FDA0003559204140000042
is the maximum value of damage equivalent stress in one cycle, damage equivalent stress sigma*The formula for calculating (a) is as follows,
Figure FDA0003559204140000043
introduction of a factor that considers the hardness-related rate of accumulation of damage
Figure FDA0003559204140000044
The formula (16) is corrected so that,
Figure FDA0003559204140000045
is expressed by the formula (14), corrected DpThe expression is as follows:
Figure FDA0003559204140000046
5. the fretting fatigue life prediction method considering surface hardness and plastic strain according to claim 4, wherein: in the step (5), the calculation results of the step (3) and the step (4) are integrated to obtain the damage parameters, specifically,
definitions D and Dp、DeThe relational expression of (1) is:
D＝max{De，Dp} (19)
namely, D is considered to be DeAnd DpOf (2) is calculated.
6. The method for predicting the fretting fatigue life taking surface hardness and plastic strain into consideration as claimed in claim 1, wherein when a damage parameter of a unit reaches 0.92, the unit is considered to be damaged and failed, no force is transmitted, the rigidity of the unit is reduced, and rigidity correction is performed; when the crack formed by the failed cell reached 200 μm, the part was considered to have failed in fatigue, the calculation was stopped and the total number of cycles was recorded.
CN202210288410.5A 2022-03-22 2022-03-22 Fretting fatigue life prediction method considering surface hardness and plastic strain Pending CN114611364A (en)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109837549A (en) * 2017-11-25 2019-06-04 中国地质大学（北京） A kind of method of the titanium alloy surface preparation anti-fine motion strengthening layer of antifriction
CN110348056A (en) * 2019-06-12 2019-10-18 南京航空航天大学 A kind of Temperature Fretting fatigue life prediction model and its method based on continuum damage mechanics
CN111090953A (en) * 2019-12-12 2020-05-01 重庆大学 Contact fatigue failure analysis method based on material damage theory and wear coupling
CN112948993A (en) * 2021-01-28 2021-06-11 南京航空航天大学 Fretting fatigue life prediction method considering abrasion influence under spectral load
CN113158511A (en) * 2021-03-18 2021-07-23 南京航空航天大学 Fretting fatigue life prediction model and method considering surface roughness

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109837549A (en) * 2017-11-25 2019-06-04 中国地质大学（北京） A kind of method of the titanium alloy surface preparation anti-fine motion strengthening layer of antifriction
CN110348056A (en) * 2019-06-12 2019-10-18 南京航空航天大学 A kind of Temperature Fretting fatigue life prediction model and its method based on continuum damage mechanics
CN111090953A (en) * 2019-12-12 2020-05-01 重庆大学 Contact fatigue failure analysis method based on material damage theory and wear coupling
CN112948993A (en) * 2021-01-28 2021-06-11 南京航空航天大学 Fretting fatigue life prediction method considering abrasion influence under spectral load
CN113158511A (en) * 2021-03-18 2021-07-23 南京航空航天大学 Fretting fatigue life prediction model and method considering surface roughness

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
吴博伟 等: ""基于连续介质损伤力学的高温微动疲劳"", 《航空动力学报》 *
陈旭 等: ""激光冲击强化对钛合金高温微动疲劳寿命的影响"", 《推进技术》 *
陈旭: ""激光强化工艺对TC11材料的高温微动疲劳寿命影响研究"", 《中国优秀硕士学位论文全文数据库 工程科技Ⅱ辑》 *

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