CN-122016919-A - Prediction method of damage of pore defects to high-temperature alloy force and heat properties

CN122016919ACN 122016919 ACN122016919 ACN 122016919ACN-122016919-A

Abstract

The invention provides a method for predicting high-temperature alloy thermal-mechanical damage by pore defects, which comprises the steps of slicing and sampling a high-temperature alloy to be detected, observing a tangent surface microscopic structure based on a scanning electron microscope to obtain an SEM picture of the high-temperature alloy microscopic structure to be detected, marking the pore defects in the SEM picture, counting the size and morphological distribution of the pore defects, calculating the porosity of the high-temperature alloy to be detected, establishing a unit cell model of the high-temperature alloy microscopic structure to be detected, which is geometrically similar to the SEM picture under the porosity, and dividing the unit cell model into grids, applying temperature boundary conditions to the unit cell model after the grid division, solving to obtain high-temperature alloy equivalent heat conductivity coefficients corresponding to different porosities, applying mechanical boundary conditions to the unit cell model after the grid division, and solving to obtain the high-temperature alloy mechanical properties corresponding to different porosities. The method solves the problem that the damage degree of the pore defect to the force and heat performance of the high-temperature alloy cannot be rapidly and effectively predicted.

Inventors

LIU WENJUN
HAN HAITAO
WU HAILONG
YU JIJUN
GAO JUNJIE
DENG DAIYING
LUO XIAOGUANG

Assignees

中国航天空气动力技术研究院

Dates

Publication Date: 20260512
Application Date: 20251229

Claims (10)

1. A method for predicting damage to thermal and mechanical properties of a superalloy by a void defect, comprising: Slicing and sampling the high-temperature alloy to be detected, and observing a section microstructure based on a scanning electron microscope to obtain an SEM (scanning electron microscope) picture of the high-temperature alloy microstructure to be detected; marking the pore defects in the SEM photo, counting the size and the morphological distribution of the pore defects, and calculating the porosity of the superalloy to be measured; establishing a unit cell model of the high-temperature alloy microstructure to be detected, which is geometrically similar to the SEM photo under the porosity, and performing grid division on the unit cell model; Applying temperature boundary conditions to the unit cell model after grid division, and solving to obtain high-temperature alloy equivalent heat conductivity coefficients corresponding to different porosities; and applying mechanical boundary conditions to the single cell model after grid division, and solving to obtain mechanical properties of the superalloy corresponding to different porosities, wherein the mechanical properties at least comprise equivalent elastic modulus, shear modulus, poisson ratio, yield strength and bearing capacity.
2. The prediction method according to claim 1, wherein the mesh size of the unit cell model division is equal to 1/10 to 1/20 times the diameter of the pores.
3. The prediction method according to claim 1, wherein the step of applying a temperature boundary condition to the mesh-divided unit cell model and solving to obtain the equivalent thermal conductivity coefficients of the superalloy corresponding to different porosities comprises: Loading periodic boundary conditions on the side of the unit cell model parallel to the heat flow: , Maintaining a balance between heat input and heat output, wherein, For the side length of the unit cell model, Representing temperature; Loading temperature difference boundary conditions on the surface of the unit cell model perpendicular to the heat flow: performing heat transfer process simulation; Deriving the equivalent thermal conductivity according to the expression of Fourier law in the three-dimensional model : Wherein, the To solve for the heat flow to the heat flow output face, Is the amount of change in temperature.
4. The prediction method according to claim 1, wherein when the mechanical property is an equivalent elastic modulus, the step of applying a mechanical boundary condition to the cell model after grid division and solving to obtain mechanical properties of the superalloy corresponding to different porosities includes: On the surface of the unit cell model, along The three direction loading coupling equations are as follows: Wherein, the 、 Is that The direction corresponds to a point on the surface, 、 Is that The direction corresponds to a point on the surface, 、 Is that The direction corresponds to a point on the surface, Is that A displacement component in the direction; Setting up The unit cell model basic loading mode is determined by the following matrix: In a matrix In (1) setting , And If the rest elements are set to zero, the expression of the elastic modulus is as follows in order to consider the y-direction stretching of poisson effect: Wherein, the Is the normal force of the section in the y direction, is extracted from the calculation result of the unit cell model, Is of a cross-sectional area, For the side length of the unit cell model, Is axially deformed.
5. The prediction method according to claim 1, wherein when the mechanical property is shear modulus, the step of applying a mechanical boundary condition to the cell model after grid division and solving to obtain mechanical properties of the superalloy corresponding to different porosities includes: On the surface of the unit cell model, along The three direction loading coupling equations are as follows: Wherein, the 、 Is that The direction corresponds to a point on the surface, 、 Is that The direction corresponds to a point on the surface, 、 Is that The direction corresponds to a point on the surface, Is that A displacement component in the direction; Setting up The unit cell model basic loading mode is determined by the following matrix: In a matrix In (1) setting The remaining elements are zeroed, and in order to consider the shear deformation parallel to the xy plane, the expression of the shear modulus is: Wherein, the For shear force, by single cell model In the direction, the nodes of the shearing force acting surface are extracted, Is the cross-sectional area of the applied force, For the corresponding original length of the shearing deformation edge, Is that And the amount of shear deformation.
6. The prediction method according to claim 1, wherein when the mechanical property is poisson's ratio, the step of applying a mechanical boundary condition to the cell model after grid division and solving to obtain mechanical properties of the superalloy corresponding to different porosities includes: On the surface of the unit cell model, along The three direction loading coupling equations are as follows: Wherein, the 、 Is that The direction corresponds to a point on the surface, 、 Is that The direction corresponds to a point on the surface, 、 Is that The direction corresponds to a point on the surface, Is that A displacement component in the direction; Setting up The unit cell model basic loading mode is determined by the following matrix: In a matrix In (1) setting , And If the rest elements are set to zero, the poisson ratio expression is as follows for the y-direction stretching taking poisson effect into consideration: Wherein, the Indicating the lateral strain, In order to provide the amount of lateral dimensional change, For the original lateral side length, , For the purpose of axial strain, Is the axial side length.
7. The prediction method according to claim 1, wherein when the mechanical property is yield strength, the step of applying a mechanical boundary condition to the cell model after grid division and solving to obtain mechanical properties of the superalloy corresponding to different porosities includes: On the surface of the unit cell model, along The three direction loading coupling equations are as follows: Wherein, the 、 Is that The direction corresponds to a point on the surface, 、 Is that The direction corresponds to a point on the surface, 、 Is that The direction corresponds to a point on the surface, Is that A displacement component in the direction; Setting up The unit cell model basic loading mode is determined by the following matrix: In a matrix In (1) setting , And If not, the rest elements are set to zero, then for y-direction compression taking the poisson effect into consideration, the method is to Dividing the load into n loads to be loaded gradually, and calculating a stress-strain calculation result of each load step; In the post-processing, the residual strain at each load step is calculated , wherein, As a result of the total strain, For the force in the y-direction, Is the cross-sectional area in the y direction, The elastic modulus of the high-temperature alloy to be measured; Traversing each load step, determining the point with the residual strain of 0.2% as the yield strength point of the superalloy to be tested, and based on a formula The yield strength is calculated, wherein, In order to achieve a yield strength, the material, For the load value at the corresponding load step, Is the original cross-sectional area of the bearing surface.
8. The prediction method according to claim 7, wherein when the mechanical property is a bearing capacity, the step of applying a mechanical boundary condition to the cell model after grid division and solving to obtain mechanical properties of the superalloy corresponding to different porosities includes: On the surface of the unit cell model, along The three direction loading coupling equations are as follows: Wherein, the 、 Is that The direction corresponds to a point on the surface, 、 Is that The direction corresponds to a point on the surface, 、 Is that The direction corresponds to a point on the surface, Is that A displacement component in the direction; Setting up The unit cell model basic loading mode is determined by the following matrix: In a matrix In (1) setting , And Setting other elements to zero without setting, taking the y-direction compression of the poisson effect into consideration, extracting the maximum stress in the unit cell model in the calculation result, determining the residual strength coefficient according to the yield strength divided by the maximum stress, and changing Up to the point where the residual intensity coefficient is determined to be less than 1, and determining the current And the bearing capacity of the superalloy to be tested is obtained.
9. A system for predicting damage to a superalloy thermal-mechanical property from a void defect, comprising: the microstructure acquisition module is used for carrying out slicing sampling on the alloy to be detected, observing the section microstructure based on a scanning electron microscope, and obtaining an SEM (scanning electron microscope) picture of the alloy microstructure to be detected; the porosity acquisition module is used for marking the pore defects in the SEM photo, counting the size and the morphological distribution of the pore defects and calculating the porosity of the superalloy to be measured; The model processing module is used for establishing a unit cell model of the high-temperature alloy microstructure to be detected, which is geometrically similar to the SEM photo under the porosity, and carrying out grid division on the unit cell model; the equivalent heat conductivity coefficient calculation module is used for applying temperature boundary conditions to the unit cell model after grid division and solving to obtain the equivalent heat conductivity coefficients of the high-temperature alloy corresponding to different porosities; The mechanical property calculation module is used for applying mechanical boundary conditions to the single cell model after grid division and solving to obtain mechanical properties of the high-temperature alloy corresponding to different porosities, wherein the mechanical properties at least comprise equivalent elastic modulus, shear modulus, poisson ratio, yield strength and bearing capacity.
10. A computer program product comprising a computer program which, when executed by a processor, implements the steps of the method of predicting pore defect damage to superalloy thermal performance as claimed in any of claims 1 to 8.

Description

Prediction method of damage of pore defects to high-temperature alloy force and heat properties Technical Field The present disclosure relates to the field of aircraft thermal protection technology, and in particular, to a method, system, and computer program product for predicting damage to superalloy thermal performance from a void defect. Background The high-temperature alloy has been widely used in the aerospace field in recent years due to the characteristics of high strength, excellent high-temperature performance, corrosion resistance and the like. The bimetal centrifugal impeller is manufactured by combining Ti 2 A1Nb superalloy with a cast gamma-TiAl superalloy impeller in the United states, and the rear-stage compressor rotor of the aero-engine is manufactured by using Ti 2 A1Nb superalloy, so that the weight reduction effect is achieved while the mechanical performance requirement is met. The Ti 2 A1Nb superalloy can be used for a long time within the temperature range of 873-1023K, and has important significance for reducing the dead weight of an aircraft and improving the fuel efficiency and the high-temperature service performance. Most of the parts used by the high-temperature alloy are hot forming parts, while the high-temperature alloy has high thermal deformation resistance, has the problems of tissue sensitivity and the like in the cogging forging of cast ingots and the secondary forging or rolling process of blanks such as bars, plates, rings and the like, has the problem that the tissue uniformity is difficult to ensure, and has the defects of pores and the like in the microstructure of the forming parts, so that the mechanical rigidity and the heat transfer performance of the material are reduced. It is important to predict the damage of pore defects to the thermal and mechanical properties of the superalloy. Disclosure of Invention It is an aim of embodiments of the present disclosure to provide a method, system and computer program product for predicting damage to superalloy thermal performance by void defects, which solve the problems of the prior art. The method for predicting the thermal performance damage of the high-temperature alloy by using the pore defects comprises the following steps of slicing and sampling the high-temperature alloy to be detected, observing a tangent surface microstructure based on a scanning electron microscope to obtain an SEM picture of the high-temperature alloy microstructure to be detected, marking the pore defects in the SEM picture, counting the size and the morphological distribution of the pore defects, calculating the porosity of the high-temperature alloy to be detected, establishing a unit cell model of the high-temperature alloy microstructure to be detected, which is geometrically similar to the SEM picture under the porosity, and conducting grid division on the unit cell model, applying temperature boundary conditions on the unit cell model after grid division, solving to obtain high-temperature alloy equivalent heat conductivity coefficients corresponding to different porosities, and applying mechanical boundary conditions on the unit cell model after grid division, solving to obtain the high-temperature alloy mechanical properties corresponding to different porosities, wherein the mechanical properties at least comprise equivalent elastic modulus, shear modulus, poisson ratio, yield strength and bearing capacity. The embodiment of the disclosure also provides a prediction system for the thermal-mechanical damage of the high-temperature alloy by the pore defects, which comprises a mesostructure acquisition module, a porosity acquisition module, a model processing module, an equivalent heat conduction coefficient calculation module and a mechanical property calculation module, wherein the mesostructure acquisition module is used for carrying out slice sampling on the high-temperature alloy to be detected, observing the section mesostructure based on a scanning electron microscope to obtain an SEM picture of the mesostructure of the high-temperature alloy to be detected, the porosity acquisition module is used for marking the pore defects in the SEM picture, counting the size and the morphological distribution of the pore defects, calculating the porosity of the high-temperature alloy to be detected, the model processing module is used for establishing a unit cell model of the mesostructure of the high-temperature alloy to be detected, which is geometrically similar to the SEM picture under the porosity, and carrying out grid division on the unit cell model, the equivalent heat conduction coefficient calculation module is used for applying temperature boundary conditions to the unit cell model after grid division to solve to obtain the equivalent heat conduction coefficients of the high-temperature alloy corresponding to different porosities, and the mechanical property calculation module is used for applying mechanical boundary conditions