A method and system for quantitatively calculating the proportion of valve guide hole porosity of an engine and the uniformity of the distribution

Abstract

The application provides a method and system for quantitatively counting the proportion of pores and the uniformity of distribution of an engine valve guide hole, and the method comprises the following steps: S1: cutting treatment is performed on a sample of the engine valve guide to obtain a sample containing an observation surface; S2: polishing treatment and polishing treatment are performed on the observation surface on the sample; S3: the sample containing the observation surface is placed in a heating furnace for heating treatment to remove oil; S4: the sample containing the observation surface after S3 treatment is subjected to grinding and polishing treatment again and then ultrasonic cleaning; S5: the sample after S4 treatment is observed using a Leica microscope, image data is obtained, a second phase measurement program is used to measure the porosity of the image data, and the proportion of pores is obtained; and S6: based on the principle of a gray level co-occurrence matrix, Python is used to process the image data, and a quantitative value of the uniformity of pore distribution is obtained, and the application can quantitatively count the pores and the uniformity of distribution of the material.

Description

[0001] The present application relates to the technical field of metal materials, and particularly relates to a method and system for quantitatively counting porosity proportion and distribution uniformity of an engine valve guide hole.

[0002] The air port system of the engine valve mechanism can open and close the intake and exhaust valves in a timely manner according to the working requirements, so that fresh air enters the cylinder and high-temperature combustion gas is discharged from the cylinder, thereby ensuring the normal operation of the engine. The valve system is an important mechanism for ensuring the opening and closing of the intake and exhaust valves, and mainly comprises a valve, a valve seat ring, a valve guide, and a valve spring. The upper half of the valve guide is in contact with the engine oil lubricating each major friction pair in the cylinder head, and bears the lateral pressure of the air port rod. The lower half of the valve guide is in contact with the high-corrosion, high-temperature and high-pressure gas in the air duct. The valve guide is made of powder metallurgy, because powder metallurgy has the advantages of low price, light weight, high material utilization rate and good lubrication performance.

[0003] The material matrix made by powder metallurgy has a certain porosity, which can store lubricating oil and is beneficial to the formation of a lubricating oil film during relative movement, thereby achieving the effect of lubrication and friction reduction. However, the existence of pores weakens the strength and hardness of the matrix. Under heavy load conditions, especially with the complication and strictness of the operating conditions of the compressor, the surface of the powder metallurgy part is prone to serious wear, which affects the stable operation of the compressor and causes the life and energy efficiency ratio of the whole machine to decrease.

[0004] At present, the porosity of the material is more qualitatively analyzed, and the porosity proportion and distribution uniformity of the material are quantitatively characterized to better understand the influence of the porosity on the performance of the material.

[0005] Therefore, it is necessary to study a method and system for quantitatively counting porosity proportion and distribution uniformity of an engine valve guide hole to overcome the deficiencies of the prior art, so as to solve or alleviate one or more of the above problems.

[0006] Therefore, the present application provides a method and system for quantitatively counting porosity proportion and distribution uniformity of an engine valve guide hole, which can quantitatively count the porosity and distribution uniformity of the material.

[0007] In one aspect, the present application provides a method for quantitatively counting porosity proportion and distribution uniformity of an engine valve guide hole, which comprises the following steps:

[0008] S1: cutting treatment is performed on a sample of the engine valve guide to obtain a sample containing an observation surface;

[0009] S2: polishing treatment and polishing treatment are performed on the observation surface of the sample;

[0010] ​​​S3: Put the sample containing the observation surface into a heating furnace for heating treatment to remove machine oil;

[0011] S4: After the sample containing the observation surface after S3 treatment is re-polished, ultrasonic cleaning is performed;

[0012] S5: The sample after S4 treatment is observed using a Leica microscope, image data is obtained, and a second phase measurement program is used to measure the porosity of the image data to obtain the porosity ratio;

[0013] S6: Based on the principle of gray level co-occurrence matrix, the image data is processed using Python to obtain quantitative numerical values of pore distribution uniformity.

[0014] According to the above-mentioned aspects and any possible implementation, further provided is an implementation, wherein the cutting treatment in S1 is specifically: the sample is cut using a wire cutting instrument, and the cutting direction of the wire cutting is the length direction of the sample.

[0015] According to the above-mentioned aspects and any possible implementation, further provided is an implementation, wherein the polishing treatment in S2 is specifically: the observation surface is polished by using sandpaper, and the mesh number of the sandpaper used is 400, 800, 1000, 1500 and 2000.

[0016] According to the above-mentioned aspects and any possible implementation, further provided is an implementation, wherein the polishing medium used in S2 is a 3.5-grit diamond polishing spray.

[0017] According to the above-mentioned aspects and any possible implementation, further provided is an implementation, wherein the heating furnace used in S3 is a muffle furnace, the heating temperature is 300°C, and the heating time is 20 min.

[0018] According to the above-mentioned aspects and any possible implementation, further provided is an implementation, wherein the ultrasonic device in S4 is an ultrasonic cleaner, the ultrasonic cleaner has a heating function, the cleaning medium is a 5g / L NaOH solution, and the temperature during cleaning is 60°C.

[0019] According to the above-mentioned aspects and any possible implementation, further provided is an implementation, wherein the magnification observed in S5 is 100X, and the gray scale threshold in the second phase measurement program is 0-106.

[0020] According to the above-mentioned aspects and any possible implementation, further provided is an implementation, wherein the gray level co-occurrence matrix in S6 reflects the number of times that a certain shape of pixel pair appears in the entire image in the gray scale image:

[0021] P(i, j|a, b, theta)={(x, y) | f(x, y)=i, f(x+a, y+b)=j}, x, y=0, 1...L-1

[0022] In the formula, P is the value of the gray level co-occurrence matrix at point (x, y), indicating the frequency of a specific gray value combination appearing in the image; a and b are distance difference values, which are selected according to the characteristics of the texture period distribution, and when there is no characteristic parameter, a and b are both 1 (pixel); theta is the scanning direction, corresponding to horizontal (0°), vertical (90°) and left (45°) and right (135°) diagonal line direction scanning of the pixel pair combination.

[0023] According to the aspect and any possible implementation manner as described above, the system for quantitatively calculating the porosity ratio and the uniformity of the distribution of the engine valve guide hole further comprises:

[0024] A sample cutting processing module is configured to perform cutting processing on a sample of the engine valve guide to obtain a sample containing an observation surface;

[0025] A sample grinding and polishing processing module is configured to perform grinding processing and polishing processing on the observation surface of the sample;

[0026] A heat treatment module is configured to place the sample containing the observation surface in a heating furnace to perform heating treatment to remove oil;

[0027] An ultrasonic cleaning module is configured to perform ultrasonic cleaning on the sample containing the observation surface after the grinding and polishing processing.

[0028] A porosity ratio obtaining module is configured to observe the processed sample using a Leica microscope, obtain image data, and perform porosity measurement on the image data using a second phase measurement program to obtain the porosity ratio.

[0029] A numerical calculation module is configured to process the image data using Python based on the principle of the gray level co-occurrence matrix to obtain a quantitative numerical value of the uniformity of the distribution of the pores.

[0030] According to the aspect and any possible implementation manner as described above, the system for quantitatively calculating the porosity ratio and the uniformity of the distribution of the engine valve guide hole further comprises:

[0031] Compared with the prior art, the present application can obtain the following technical effects:

[0032] The present application can quantitatively calculate the porosity ratio and the uniformity of the distribution of the pores, and better establish the relationship between the porosity and the performance of the material.

[0033] Of course, implementing any product of the present application does not necessarily need to achieve all the technical effects described above at the same time. BRIEF DESCRIPTION OF DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0035] Figure 1 is a metallographic photo of the valve guide material provided by an embodiment of the present application under 100X;

[0036] Figure 2 is a photo and statistical result graph after the second phase process provided by an embodiment of the present application;

[0037] Figure 3 is four photos for statistical pore distribution uniformity provided by an embodiment of the present application;

[0038] Figure 4 is a statistical result graph based on a gray level co-occurrence matrix provided by an embodiment of the present application. Figure 3 DETAILED DESCRIPTION

[0039] In order to better understand the technical solutions of the present application, the embodiments of the present application will be described in detail below with reference to the drawings.

[0040] It should be clear that the described embodiments are only some of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without any creative effort belong to the scope of protection of the present application.

[0041] The terms used in the embodiments of the present application are only for the purpose of describing the specific embodiments, and are not intended to limit the present application. The singular forms "a", "said" and "the" used in the embodiments of the present application and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise.

[0042] The present application provides a method for quantitatively and statistically analyzing the proportion and distribution uniformity of the pores of the engine valve guide, and the steps are as follows:

[0043] S1: use a wire cutting machining instrument to cut the workpiece to obtain the observation surface of the required sample.

[0044] S2: polish the observation surface with sandpaper, and then perform polishing treatment.​

[0045] S3: the sample obtained in S2 is placed in a heating furnace for heating to remove the engine oil inside.

[0046] S4: after the sample treated in S3 is re-polished, ultrasonic cleaning is performed.

[0047] S5: the sample treated in S4 is observed using a Leica microscope, and porosity measurement is performed using a second phase measurement program.

[0048] S6: based on the principle of the gray level co-occurrence matrix, the image is processed using Python to obtain quantitative numerical values of the uniformity of the pores.

[0049] The wire cutting direction in S1 is the length direction of the sample.

[0050] The grit number of the sandpaper in S2 is 400, 800, 1000, 1500, and 2000. The polishing agent in S2 is a diamond spray with a particle size of 3.5.

[0051] The heating furnace used in S3 is a muffle furnace, the heating temperature is 300 DEG C, and the heating time is 20 min.

[0052] The ultrasonic device in S4 is an ultrasonic cleaner, and the ultrasonic cleaner has a heating function. The cleaning medium in S4 is a 5 g / L NaOH solution. The temperature during cleaning in S4 is 60 DEG C.

[0053] The magnification observed in S5 is 100X, and the gray scale threshold in the second phase measurement program is 0-106.

[0054] The gray level co-occurrence matrix formula in S6 is expressed as:

[0055] P(i, j | a, b, theta) = { (x , y) | f(x, y) = i, f(x + a, y + b) = j}, x, y = 0, 1... L-1

[0056] Wherein, a, b in the formula are distance difference values, also known as adjacent intervals and offsets, which are selected according to the characteristics of the texture period distribution, and when there is no characteristic parameter, 1 (pixel) is taken; theta is the scanning direction, which corresponds to horizontal (0°), vertical (90°) and left (45°) right (135°) diagonal line direction scanning pixel pair combination.

[0057] The application also provides a system for quantitatively and statistically determining the proportion and distribution uniformity of the pores of the engine valve guide, and the system comprises:

[0058] A sample cutting processing module is used to cut the sample of the engine valve guide to obtain a sample containing an observation surface.

[0059] A sample polishing and polishing processing module is used for polishing and polishing processing on an observation surface of a sample;

[0060] A heat treatment module is used for placing a sample containing an observation surface in a heating furnace for heat treatment to remove machine oil;

[0061] An ultrasonic cleaning module is used for re-polishing and polishing the processed sample containing the observation surface and then performing ultrasonic cleaning;

[0062] A pore ratio obtaining module is used for observing the processed sample using a Leica microscope, obtaining image data, and using a second phase measurement program to measure the porosity of the image data and obtain the pore ratio;

[0063] A numerical calculation module uses Python to process the image data based on the principle of the gray level co-occurrence matrix to obtain quantitative numerical values of the pore distribution uniformity.

[0064] The application also provides a computer comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the method for quantitatively and statistically obtaining the pore ratio and the distribution uniformity of the engine valve guide according to any one of the methods.

[0065] Example 1

[0066] The metallographic photos of the valve guide samples after oil removal, polishing and polishing treatment under the Leica microscope 100X can clearly see the black part as the pore, and the effect is as shown in Figure 1 .

[0067] The image obtained by processing the picture of example 1 through the second phase analysis program of the Leica microscope, wherein the green part is the pore part, and the proportion of the green part is counted, and the effect is as shown in Figure 2 .

[0068] Example 2

[0069] The metallographic photos of the four valve guide samples after oil removal, polishing and polishing treatment under the Leica microscope 100X can qualitatively see that the pore uniformity of a and b is better than that of c and d, and the effect is as shown in Figure 3 .

[0070] The results obtained by processing the image based on the gray level co-occurrence matrix can quantitatively see that the pore uniformity of a and b is better than that of c and d, and the effect is as shown in Figure 3 . Figure 4

[0071] ​It can be seen from the embodiment 1 that the proportion of the pores can be quantitatively counted by the method.

[0072] It can be seen from the embodiment 2 that the distribution uniformity of the pores can be quantitatively counted by the method.

[0073] The method and system for quantitatively counting the proportion and distribution uniformity of the pores of the engine valve guide are described in detail above. The description of the above embodiments is only used to help understand the method and its core idea. For those skilled in the art, according to the idea of the present application, the specific implementation and application range will be changed, and the content of the description should not be understood as a limitation of the present application.

[0074] As some terms are used in the description and claims to refer to certain components. Those skilled in the art should understand that hardware manufacturers may use different names to refer to the same component. The description and claims of the present application do not distinguish components by name, but by the functional difference of the components. As mentioned throughout the description and claims, "including" and "including" are open terms, which should be interpreted as "including / including but not limited to". "Approximately" means within an acceptable error range, and those skilled in the art can solve the technical problem within a certain error range, and basically achieve the technical effect. The subsequent description of the specification is a preferred embodiment of the present application, which is for the purpose of illustrating the general principles of the present application, and is not intended to limit the scope of the present application. The scope of protection of the present application is defined by the appended claims.

[0075] It should also be noted that the terms "include", "contain" or any other variant thereof are intended to cover non-exclusive inclusion, so that the goods or systems including a series of elements not only include those elements, but also include other elements not explicitly listed, or include elements inherent to such goods or systems. Without more limitations, the element defined by the sentence "including a…" does not exclude the existence of other identical elements in the goods or systems including the element.

[0076] It should be understood that the term "and / or" used herein is only a description of the association relationship between the associated objects, which means that there are three relationships, for example, A and / or B, which means that there are three cases of A alone, A and B together, and B alone. In addition, the character " / " in this paper generally represents a "or" relationship between the front and rear associated objects.

[0077] The foregoing description illustrates and describes several preferred embodiments of the present application. However, it is to be understood that the application is not limited to the precise forms described, and that changes can be made therein without departing from the scope of the present application. Other embodiments of the application will be apparent to those skilled in the art from consideration of the specification and practice of the application disclosed herein. Therefore, the specification and examples are to be considered exemplary only, with a true scope and spirit of the application being indicated by the following claims.

Claims

1. A method for quantifying statistical valve guide bore hole porosity fraction and distribution uniformity of an engine, characterized by, The method comprises the following steps: S1: cutting treatment is performed on a sample of an engine valve guide to obtain a sample containing an observation surface; S2: polishing treatment and polishing treatment are performed on the observation surface on the sample; S3: the sample containing the observation surface is placed in a heating furnace for heating treatment to remove engine oil; S4: the sample containing the observation surface after S3 treatment is re-polished and then ultrasonic cleaned; S5: Leica microscope is used to observe the sample after S4 treatment, image data is obtained, and a second phase measurement program is used to measure the porosity of the image data to obtain a porosity ratio; S6: based on the principle of gray level co-occurrence matrix, Python is used to process the image data to obtain a quantitative value of the uniformity of the pore distribution; The cutting treatment in S1 is specifically: the sample is cut by a wire cutting instrument, and the cutting direction of the wire cutting is the length direction of the sample; The polishing treatment in S2 is specifically: the observation surface is polished by sandpaper, and the sandpaper used has a mesh number of 400, 800, 1000, 1500 and 2000; The polishing medium used in the polishing in S2 is a 3.5-grit diamond polishing spray; The heating furnace used in S3 is a muffle furnace, the heating temperature is 300°C, and the heating time is 20 minutes; The ultrasonic equipment in S4 is an ultrasonic cleaner, the ultrasonic cleaner has a heating function, the cleaning medium is a 5g / L NaOH solution, and the cleaning temperature is 60°C; The magnification for observation in S5 is 100X, and the gray scale threshold in the second phase measurement program is 0-106; In S6, the gray level co-occurrence matrix reflects the number of times that a certain shape of pixel pair appears in the entire image in the gray scale image: In the formula, P is the value of the gray level co-occurrence matrix at point (x, y), which represents the frequency of a specific gray value combination appearing in the image; a and b are distance difference values, which are selected according to the characteristics of the texture period distribution, and when there is no characteristic parameter, a and b are both 1; θ is the scanning direction, which corresponds to scanning the pixel pair combination in the horizontal, vertical and left-right diagonal directions.

2. A system for quantifying statistical valve guide bore porosity fraction and distribution uniformity of an engine, the system comprising: The system comprises: a sample cutting treatment module for cutting treatment on a sample of an engine valve guide to obtain a sample containing an observation surface; a sample polishing and polishing treatment module for polishing treatment and polishing treatment on the observation surface on the sample; a heat treatment module for placing the sample containing the observation surface in a heating furnace for heating treatment to remove engine oil; an ultrasonic cleaning module for re-polishing and polishing the sample containing the observation surface after treatment and then ultrasonic cleaning; a porosity ratio obtaining module for observing the sample after treatment using a Leica microscope, obtaining image data, using a second phase measurement program to measure the porosity of the image data, and obtaining a porosity ratio; a numerical calculation module for processing the image data based on the principle of gray level co-occurrence matrix to obtain a quantitative value of the uniformity of the pore distribution.

3. A computer comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The processor executes the computer program to realize the method for quantitatively and statistically measuring the porosity ratio and the uniformity of the distribution of the engine valve guide according to claim 1.

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