CN115575450A - Method for evaluating impact erosion failure of surface protection material particles - Google Patents

Method for evaluating impact erosion failure of surface protection material particles Download PDF

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CN115575450A
CN115575450A CN202210164473.XA CN202210164473A CN115575450A CN 115575450 A CN115575450 A CN 115575450A CN 202210164473 A CN202210164473 A CN 202210164473A CN 115575450 A CN115575450 A CN 115575450A
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damage
area
erosion
test
volume loss
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范金娟
孙炜
刘昌奎
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AECC Beijing Institute of Aeronautical Materials
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00Investigating strength properties of solid materials by application of mechanical stress
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Abstract

The invention provides a method for evaluating impact erosion failure of particles of a protective material. The method comprises the steps of determining a three-dimensional coordinate axis according to the appearance of an impact erosion surface, selecting damage positions at certain intervals to measure the depth of erosion damage, combining ORIGIN software, adopting Gauss function fitting to obtain a damage depth change equation, carrying out integral calculation on a depth curve to obtain the section area of a test area, multiplying the section area of the test area by the test width of each time to obtain the volume loss amount of each time, superposing the volume loss amount of each time measured in the damage area according to a differential principle to obtain the total volume loss amount of the damage area, drawing a damage three-dimensional appearance graph, quantitatively evaluating the damage degree and the erosion rate of a protective material, providing a failure criterion according to the damage degree, and evaluating the impact erosion resistance of the material according to the erosion rate. The method can reflect the average damage phenomenon of the protective material due to impact erosion of particles, can quantitatively describe local microscopic change of the protective material, and is easy to operate and wide in application.

Description

Method for evaluating impact erosion failure of surface protection material particles
Technical Field
The invention belongs to the technical field of protective materials, and relates to a method for evaluating particle impact erosion failure of a surface protective material in the field of aviation.
Background
The phenomenon of impact erosion of particulate matter widely exists in the industries of aviation, aerospace, machinery, energy and the like, and is one of the main reasons for material damage or component failure. The surface protective material has more prominent harm in the military field, and the sand dust and sand grains in the air and the ground can cause erosion and abrasion to the surfaces of parts such as an airplane radome, a wing, a helicopter rotor blade and the like, thereby greatly reducing the service life of the parts, so the surface protective material is widely applied to the surfaces of metal, nonmetal and composite material components. The failure of the surface protection material can cause the matrix material to be rapidly failed due to impact erosion of particles, so that the matrix material must be replaced periodically in the using process, and a reasonable failure evaluation method is needed to determine the failure criterion and the replacement period of the matrix material.
The existing failure evaluation method mainly adopts a quality loss method. The surface protection material has small relative density and thin thickness, generally dozens to hundreds of microns, and compared with the base material, the proportion of the surface protection material in the test piece is smaller, so that even if the surface protection material reaches a failure state, the quality loss is less, particularly under the condition that sand grains are embedded, the quality is not lost, but increased, the failure evaluation of the protection material is difficult, and the test error is larger. The method reflects the average phenomenon of the damage of the protective material, and the quantitative characterization of local areas can not be carried out. For the surface protection material of the metal component, the failure degree of the surface protection material can be evaluated by measuring impedance by adopting an electrochemical analysis method, but the method is not suitable for a non-conductive base material and cannot carry out quantitative analysis on a local area.
Disclosure of Invention
The purpose of the invention is:
the method overcomes the defects that the quality loss evaluation for the surface protection material has large error, the electrochemical method can only represent the metal surface protection coating and the like, solves the problems that the average loss of the protection material can only be reflected by the existing method and the precision is insufficient and the like, establishes a method capable of quantitatively and accurately representing the damage degree and the damage rate of the surface protection material caused by the particle impact erosion, and determines the failure evaluation method of the particle impact erosion of the protection material.
The technical scheme of the invention is as follows:
aiming at the protective material which is impacted by particles in the test process or the service process, equipment such as a laser confocal microscope or a roughness meter is adopted, a coordinate axis is determined according to the impact erosion shape, the damage position is selected to measure the erosion damage depth, the measured depth is subjected to Gauss function fitting to obtain a curve equation, the erosion damage area is obtained through integral calculation, the erosion damage area is multiplied by the width of a tested micro-area to obtain the volume of the erosion damage of the micro-area, the volumes of the erosion damage measured each time are added to obtain the total volume of the erosion damage, and a damage three-dimensional shape graph can be drawn according to the measured data. The method is visual and vivid, can quantitatively evaluate the damage degree and the erosion rate of the protective material, provides a failure criterion according to the damage degree, and evaluates the erosion resistance of the material according to the erosion rate. And a characterization and evaluation method is provided for the development and improvement of the protective material and the life analysis.
Preferably, the method for evaluating the erosion failure of the surface protective material particles comprises the following steps:
s1, determining coordinate axes according to damage appearance by using a laser confocal microscope or a roughness meter, selecting a damage position to measure the depth of erosion damage of a surface, and fitting by combining Origin software to obtain a damage depth change equation;
s2, performing integral calculation on the depth curve to obtain the section area of the test area;
s3, multiplying the area of the section of the test area by the test width of each time to obtain the volume loss of each time;
s4, superposing the volume loss measured in each time of the damaged area according to a differential principle to obtain the total volume loss of the damaged area, drawing a damaged three-dimensional shape, and quantitatively evaluating the damage degree and the erosion rate of the protective material;
s5, providing a failure criterion according to the damage degree;
and S6, evaluating the erosion resistance of the material according to the erosion rate.
Preferably, in the step S1:
determining a three-dimensional coordinate axis according to the damaged morphology, and selecting a symmetrical axis of the damaged morphology as a Y-axis direction; the direction which is vertical to the Y axis and is in the same plane is determined as the X axis direction; the damage depth direction is the Z-axis direction.
Preferably, in the S1 step:
selecting a damage position to measure the depth of the surface erosion damage, and determining the moving direction of the objective lens along the Y-axis direction from the damage edge; the length of the damage in the X-axis direction determines the number of measurements, i = maximum width of the damage in the X-axis direction/maximum width of the damage Δ X measured each time.
Preferably, in the step S1: and (3) combining Origin software, and fitting by using Gauss function to obtain a damage depth change curve equation z = f (y). I.e. the variation of the lesion depth z along the Y-axis coordinate.
Preferably, in the step S2: the depth curve is subjected to integral calculation to obtain the section area of the test area, and the calculation equation is shown as equation 1
Figure RE-GDA0003857135900000031
Wherein: si is the area obtained by the ith measurement and calculation; z = f (y), z being the lesion depth of the measurement point; z is a radical of 0 Is the coordinate on which the Z axis lies, and is typically 0.Y is the Y-axis coordinate of the point, and the value range of Y is Y 1 To y 2 。 y 1 To measure the Y-axis coordinate of the starting point, Y 2 Is the Y-axis coordinate of the measurement end point. dy is the distance between two measurement points and is related to the instrument selected for the test and the magnification factor.
Preferably, in the step S3: multiplying the cross-sectional area of the test region by the test width of each time to obtain the volume loss of each time, and calculating the equation as shown in equation (2)
Vi=Δx×Si (2)
Wherein: vi is the measured region damage volume calculated after the ith measurement. Δ X is the width of the damage in the X-axis direction for the ith measurement. Si is the area calculated by the ith measurement. The test width is determined according to the size of the damaged area and the test precision.
Preferably, in step S4: and superposing the volume loss measured in each time of the damaged area to obtain the total volume loss of the damaged area, and drawing the damaged three-dimensional shape to obtain the damaged average value and the damaged micro-area shape.
V=∑ i=1-n V i (3)
Wherein: v is the total volume loss of the lesion. i is the number of measurements. 1 is the first measurement. n is the nth measurement. V i The volume loss obtained for the ith calculation.
Preferably, a failure criterion is proposed based on the extent of damage. The failure criterion is a specified value for volume loss. When the volume loss reaches a specified value, the failure of the protective material can be judged. The greater the volume loss, the more susceptible to impact erosion failure for the same particle impact time.
Preferably, the erosion resistance of the material is evaluated in terms of erosion rate. Erosion rate = volume loss/test time or service time.
Preferably, a laser confocal microscope or a roughness meter is adopted, and the precision of a test system is 0.1 mu m;
where erosion rate = volume loss/test time or service time.
The invention has the advantages and beneficial effects that:
the method has the advantages that the method can overcome the defects that the quality loss evaluation protective material has large damage error and is not suitable for the material with sand embedded; the electrochemical method can only represent the defects of metal surface protective materials and the like, solves the problems that the prior method can only reflect the average loss phenomenon of the protective materials and the like, can quantitatively and accurately represent the damage degree and the damage rate of the surface protective materials caused by particle erosion, establishes the failure criterion of the protective materials in the service process, can reflect the average phenomenon of the protective materials, and can quantitatively describe the local microscopic change of the coating. The method is easy to operate and has wide application. The method can quantitatively evaluate the capability of the protective material for resisting the impact erosion of the particles, can visually provide the damage appearance of the sand erosion, and is suitable for evaluating the surface protective material taking the metal material as the matrix and the surface protective material taking the non-metal material as the matrix.
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In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments of the present invention will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
FIG. 1 is a schematic view of the macro topography of impact erosion damage;
FIG. 2 is a schematic view of coordinate axes and depth measurements;
FIG. 3 is a schematic diagram of an erosion damage zone test;
FIG. 4 is a schematic view of an erosion damage depth fitting curve;
FIG. 5 is a schematic diagram of the three-dimensional topography of the erosion damage.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. It is to be understood that the embodiments described are only a few embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
It should be noted that, in the case of conflict, the embodiments and features of the embodiments of the present invention may be combined with each other, and the respective embodiments may be mutually referred to and cited. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.
The invention provides a method for evaluating impact erosion failure of particles of a protective material. The method aims at the protective material which is impacted and eroded by particles in the test process or the service process. Determining a three-dimensional coordinate axis according to the impact erosion surface appearance by using a laser confocal microscope or a roughness meter, selecting damage positions at certain intervals to measure the erosion damage depth, combining ORIGIN software to obtain a damage depth change equation by using Gauss function fitting, performing integral calculation on a depth curve to obtain the section area of a test area, multiplying the section area of the test area by the test width of each time to obtain the volume loss amount of each time, superposing the volume loss amount of each time measured in the damage area according to a differential principle to obtain the total volume loss amount of the damage area, drawing a damage three-dimensional appearance graph, quantitatively evaluating the damage degree and the erosion rate of the protective material, providing a failure criterion according to the damage degree, and evaluating the impact erosion resistance of the material according to the erosion rate.
The method can reflect the average damage phenomenon of the protective material due to impact erosion of particles, and can quantitatively describe local microscopic changes of the protective material. The method is easy to operate, wide in application range, and more suitable for the protective material with the surface easily embedded with particles, and can provide a basis for evaluation of particle impact erosion resistance failure of the protective material and determination of a replacement period.
FIG. 1 is a schematic view of a sand erosion macro-topography;
referring to FIG. 1, FIG. 1 depicts the surface macro-topography of a polyurethane protective tape having a thickness of about 300 μm after 5min of sand erosion.
FIG. 2 is a schematic diagram of an erosion damage zone test;
referring to fig. 2, fig. 2 illustrates that three-dimensional coordinate axes are determined according to the damage profile, and a symmetry axis of the damage profile is selected as a Y-axis direction; the direction which is vertical to the Y axis and is in the same plane is determined as the X axis direction; the damage depth direction is Z-axis direction
FIG. 3 is a schematic diagram of an erosion damage zonal test;
referring to fig. 3, fig. 3 illustrates that the depth of the surface erosion damage is measured by selecting the damage position, and the moving direction of the objective lens is determined along the Y-axis direction from the damage edge; the length of the damage in the X-axis direction determines the number of measurements, i = maximum width of the damage in the X-axis direction/maximum width of the damage Δ X measured each time.
FIG. 4 is a schematic view of an erosion damage depth fitting curve;
referring to fig. 4, fig. 4 illustrates how the lesion depth curve equation z = f (y) is obtained by using Gauss function fitting in combination with Origin software. I.e. the variation of the lesion depth z along the Y-axis coordinate.
FIG. 5 is a schematic diagram of the three-dimensional topography of the erosion damage.
Referring to FIG. 5, FIG. 5 illustrates the integration of the depth curve to obtain the cross-sectional area of the test area, the calculation equation is shown in equation 1
Figure RE-GDA0003857135900000061
Wherein: si is the area obtained by the ith measurement and calculation; z = f (y), z being the lesion depth at the measurement point; z is a radical of 0 Is the coordinate on which the Z axis lies, and is typically 0.Y is the Y-axis coordinate of the point, and the value range of Y is Y 1 To y 2 。 y 1 To measure the Y-axis coordinate of the starting point, Y 2 Is the Y-axis coordinate of the measurement end point. dy is the distance between two measurement points and is related to the instrument selected for the test and the magnification factor.
Multiplying the cross-sectional area of the test region by the test width of each time to obtain the volume loss of each time, and calculating the equation as shown in equation (2)
Vi=Δx×Si (2)
Wherein: vi is the measured region damage volume calculated after the ith measurement. Δ X is the width of the damage in the X-axis direction for the ith measurement. Si is the area calculated by the ith measurement. And the test width is determined according to the size of the damage area and the test precision.
And superposing the volume loss measured in each time of the damaged area to obtain the total volume loss of the damaged area, and drawing the damaged three-dimensional shape to obtain the damaged average value and the damaged micro-area shape.
V=∑ i=1-n V i (3)
Wherein: v is the total volume loss of the damaged area. i is the number of measurements. 1 is the first measurement. n is the nth measurement. V i The volume loss obtained for the ith calculation.
And providing a failure criterion according to the damage degree. The failure criterion is a specified value for volume loss. When the volume loss reaches a specified value, the failure of the protective material can be judged. The greater the volume loss, the more susceptible to impact erosion failure for the same particle impact time.
And evaluating the erosion resistance of the material according to the erosion rate. Erosion rate = volume loss/test time or service time.
It should be noted that the above-mentioned flow operations may be combined and applied in different degrees, and for simplicity, implementation manners of various combinations are not described again, and those skilled in the art may flexibly adjust the sequence of the above-mentioned operation steps according to actual needs, or flexibly combine the above-mentioned steps, and the like.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solutions of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily think of various equivalent modifications or substitutions within the technical scope of the present invention, and these modifications or substitutions should be covered within the scope of the present invention.

Claims (10)

1. A method for evaluating the erosion failure of surface protection material particles is characterized by comprising the following steps:
s1, determining a coordinate axis according to the damage appearance by using a laser confocal microscope or a roughness meter, selecting a damage position to measure the depth of erosion damage of the surface, and fitting by combining Origin software to obtain a damage depth change equation;
s2, carrying out integral calculation on the depth curve to obtain the section area of the test area;
s3, multiplying the area of the section of the test area by the test width of each time to obtain the volume loss of each time;
s4, superposing the volume loss measured in each time of the damaged area according to a differential principle to obtain the total volume loss of the damaged area, drawing a damaged three-dimensional shape, and quantitatively evaluating the damage degree and the erosion rate of the protective material;
s5, providing a failure criterion according to the damage degree;
and S6, evaluating the erosion resistance of the material according to the erosion rate.
2. The method of claim 1, wherein in step S1:
determining a three-dimensional coordinate axis according to the damaged morphology, and selecting a symmetrical axis of the damaged morphology as a Y-axis direction; the direction which is vertical to the Y axis and is in the same plane is determined as the X axis direction; the damage depth direction is the Z-axis direction.
3. The method of claim 1, wherein in step S1:
selecting a damage position to measure the depth of the surface erosion damage, and determining the moving direction of the objective lens along the Y-axis direction from the damage edge; the length of the damage in the X-axis direction determines the number of measurements, i = maximum width of the damage in the X-axis direction/maximum width of the damage Δ X measured each time.
4. The method of claim 1, wherein in step S1:
and (3) combining Origin software, and fitting by using Gauss function to obtain a damage depth change curve equation z = f (y). I.e. the variation of the lesion depth z along the Y-axis coordinate.
5. The method of claim 1, wherein in the S2 step:
the depth curve is subjected to integral calculation to obtain the section area of the test area, and the calculation equation is shown as equation 1
Figure RE-FDA0003857135890000011
Wherein: si is the area obtained by the ith measurement and calculation; z = f (y), z being the lesion depth of the measurement point; z is a radical of 0 Is the coordinate on which the Z axis lies, and is typically 0.Y is the Y-axis coordinate of the point, and the value range of Y is Y 1 To y 2 。y 1 To measure the Y-axis coordinate of the starting point, Y 2 Is the Y-axis coordinate of the measurement end point. dy is the distance between two measurement points and is related to the instrument selected for the test and the magnification factor.
6. The method according to any one of claims 1-8, wherein in step S3:
multiplying the cross-sectional area of the test region by the test width of each time to obtain the volume loss of each time, and calculating the equation as shown in equation (2):
Vi=Δx×Si (2)
wherein: vi is the measured region damage volume calculated after the ith measurement. Δ X is the width of the damage in the X-axis direction for the ith measurement. Si is the area calculated from the ith measurement. The test width is determined according to the size of the damaged area and the test precision.
7. The method according to any one of claims 1 to 8, wherein in step S4:
and superposing the volume loss measured in each time of the damaged area to obtain the total volume loss of the damaged area, and drawing the damaged three-dimensional shape to obtain the damaged average value and the damaged micro-area shape.
V=∑ i=1-n V i (3)
Wherein: v is total volume loss of the damaged area, i is the number of measurements, 1 is the first measurement, n is the nth measurement, V i The volume loss obtained for the ith calculation.
8. The method of claim 1, wherein in the S5 step:
and providing a failure criterion according to the damage degree. The failure criterion is a specified value for volume loss. When the volume loss reaches a specified value, the failure of the protective material can be judged. The greater the volume loss, the more susceptible to impact erosion failure for the same particle impact time.
9. The method of claim 1, wherein in step S6:
and evaluating the erosion resistance of the material according to the erosion rate. Erosion rate = volume loss/test time or service time.
10. The method of any one of claims 1-9, wherein:
a laser confocal microscope or a roughness meter is adopted, and the precision of a test system is 0.1 mu m;
wherein erosion rate = volume loss/test time or service time.
CN202210164473.XA 2022-02-22 2022-02-22 Method for evaluating impact erosion failure of surface protection material particles Pending CN115575450A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117131729A (en) * 2023-08-15 2023-11-28 南京工业大学 Method for evaluating integrity of composite crack-containing structure under action of ballast load

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117131729A (en) * 2023-08-15 2023-11-28 南京工业大学 Method for evaluating integrity of composite crack-containing structure under action of ballast load
CN117131729B (en) * 2023-08-15 2024-03-19 南京工业大学 Method for evaluating integrity of composite crack-containing structure under action of ballast load

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