Thickness detection method for HVOF coating based on energy dispersion X-ray fluorescence spectrophotometer

Abstract

The invention discloses a method for detecting the thickness of an HVOF coating based on an energy dispersion X-ray fluorescence spectrophotometer, qualitative analysis is carried out on an infiltrated layer, then quantitative analysis is carried out on the infiltrated layer, the method can be directly applied to thickness detection of the HVOF coating, and meanwhile, the method can also be suitable for other thermal spraying processes. The infiltrated layer algorithm also has applicability, comprises traditional metal surface treatment processes such as hot dip galvanizing, and makes up the disadvantage that the same elements in the infiltrated layer of a traditional energy dispersion X fluorescence spectrophotometer cannot be accurately stripped and calculated.

Description

Technical Field

[0001] The invention relates to the technical field of optical instruments, and in particular to a thickness detection method for HVOF coating based on an energy dispersion X-ray fluorescence spectrometer. Background Art

[0002] High Velocity Oxygen Fuel (HVOF) coating is a thermal spray coating process used to improve or restore the surface (properties or geometry) of a component. This surface engineering technology better extends the service life of equipment by improving erosion resistance, wear resistance, and corrosion resistance. HVOF spraying was developed in the 1980s and is a subset of thermal spraying. The working principle of HVOF spraying is to mix fluid fuel and oxygen, feed them into a combustion chamber and ignite them. The resulting gas has extremely high temperature and pressure and is ejected through the nozzle at supersonic speed. The powder is injected into the high-speed gas flow and the powder is partially melted. The hot gas flow and powder are directed to the surface to be coated. The resulting dense coating has low porosity and high bonding strength, and has many advantages such as corrosion resistance.

[0003] Since the HVOF spraying process is accompanied by high temperature treatment of thousands of degrees Celsius, a diffusion layer often appears. The diffusion layer will mix the element content of the substrate and the coating, and change according to the different process conditions. Therefore, for the energy dispersive X-ray fluorescence spectrometer, the diffusion layer will directly affect the test results, resulting in poor data accuracy.

[0004] A transitional coating between the substrate and the coating. The principle of its production is that after high-temperature treatment, some elements of the coating and some elements of the substrate penetrate each other to form a coating with special properties. For actual use scenarios, this infiltration layer is sometimes beneficial to the special performance of the product, but sometimes it is harmful. For most energy dispersive X-ray fluorescence spectrometers, the infiltration layer is basically ignored for the thickness detection of HVOF coatings. Therefore, for this model, the algorithm can more accurately detect the actual thickness of the HVOF coating.

[0005] Since the elements of the diffusion layer are basically the same as those of the outer coating and also contain the elements of the substrate, it is basically difficult to perform stripping calculations using most energy dispersive X-ray fluorescence spectrometers.

[0006] Therefore, how to provide a thickness detection method for HVOF coating based on energy dispersive X-ray fluorescence spectrometer to solve the problems existing in the prior art is of great significance to its application. Summary of the invention

[0007] In view of this, the purpose of the present application is to provide a thickness detection method for HVOF coating based on energy dispersive X-ray fluorescence spectrometer to solve the problem.

[0008] To achieve the above object, the present invention provides the following technical solutions:

[0009] A method for detecting the thickness of an HVOF coating based on an energy dispersive X-ray fluorescence spectrometer comprises the following steps:

[0010] S1: Qualitative analysis of the permeate layer;

[0011] S2: Quantitative analysis of the infiltration layer.

[0012] Preferably, the specific steps of performing qualitative analysis on the S1 infiltration layer are as follows:

[0013] S1.1: Qualitative analysis of different elements in the analysis results of the permeated layer;

[0014] S1.2: Determine whether there is an obvious gradient in the analysis results.

[0015] Preferably, the S1.1 includes:

[0016] S1.11: Aluminizing project - Ni nickel element qualitative analysis;

[0017] S1.12: Aluminizing project - qualitative analysis of chromium element;

[0018] S1.13: Aluminizing project - qualitative analysis of Nb niobium element.

[0019] Preferably, the elements involved in the S1.1 item are calculated and analyzed using the same method to obtain an equivalent attenuation diagram.

[0020] Preferably, the specific steps of the quantitative analysis of the S2 permeation layer are as follows:

[0021] S2.1: Mark the coatings, with the outer coating as f1, the transition layer as f2, and the substrate as f3:

[0022] S2.2: Calculate and obtain the accurate thickness of the outer coating f1;

[0023] S2.3: Calculate the thickness of the transition layer f2;

[0024] S2.4: Peel off the strength of other identical elements that distinguish the base material f3 and the transition layer f2.

[0025] Preferably, in S2: assuming that the outer coating layer f1 and the transition layer f2 have the same element g, the fluorescence intensity of the element detected by the energy dispersive X-ray fluorescence spectrometer is G I0 .

[0026] Preferably, the calculation steps of S2.2 are as follows:

[0027] The relationship between the outer coating f1 and the transition layer f2 is as follows (assuming the thickness of the outer coating f1 is x): ax+be^-U 12 cX=d;

[0028] Where: abcd is a non-zero natural number, U12 is an absorption coefficient of the outer coating f1 and the transition diffusion layer f2;

[0029] By solving for the value of x, we obtain the exact thickness of the outer coating f1.

[0030] Preferably, the calculation steps of S2.3 are as follows:

[0031] By formula: I = I o e^-μρdx;

[0032] Where: I is the intensity of X-rays after attenuation, I 0 is the initial intensity of the incident X-ray, μ is the mass absorption coefficient of the material, ρ is the density of the material, and dx represents the thickness of the material;

[0033] Calculate the X-ray intensity I of the outer coating f1 occupied by element g 0 , and obtain the X-ray intensity G of the same element g in the transition layer f2 I0 -I 0 :

[0034] Finally, the thickness of the transition layer f2 is calculated.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] 1. The patent applied for in this article can be directly applied to the thickness detection of HVOF coatings. At the same time, the patent can also be applied to other thermal spraying processes.

[0037] 2. The algorithm of the diffusion layer involved in this patent is also applicable, including traditional metal surface treatment processes such as hot zinc infiltration, which makes up for the disadvantage that the same elements in the diffusion layer of the traditional energy dispersive X-ray fluorescence spectrometer cannot be accurately stripped and calculated.

[0038] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application so that it can be implemented in accordance with the contents of the specification, and to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the following is a detailed description of the preferred embodiments of the present application in conjunction with the accompanying drawings as follows.

[0039] Based on the detailed description of the specific embodiments of the present application in combination with the accompanying drawings below, those skilled in the art will become more aware of the above and other objects, advantages and features of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can also be obtained based on these drawings without creative work. In all drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, each element or part is not necessarily drawn according to the actual scale.

[0041] Figure 1 This is a qualitative analysis effect diagram of the Ni nickel element in the present invention;

[0042] Figure 2 This is a qualitative analysis effect diagram of the Nb niobium element in the present invention;

[0043] Figure 3 This is a qualitative analysis effect diagram of the chromium element in the present invention;

[0044] Figure 4 It is the algorithm model diagram in the present invention;

[0045] Figure 5 This is a comparison chart of the uncorrected permeation layer data in the present invention;

[0046] Figure 6 This is a comparison chart of the corrected infiltration layer data in the present invention. DETAILED DESCRIPTION

[0047] To make the purpose, technical scheme and advantages of the embodiment of the present application clearer, the technical scheme in the embodiment of the present application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiment of the present application. Obviously, the described embodiment is a part of the embodiment of the present application, rather than all of the embodiments. In the following description, specific details such as specific configuration and components are provided only to help fully understand the embodiments of the present application. Therefore, it should be clear to those skilled in the art that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present application. In addition, for clarity and brevity, the description of known functions and structures is omitted in the embodiment.

[0048] In addition, the present application may repeat reference numerals and / or letters in different examples. This repetition is for the purpose of simplicity and clarity, and does not in itself indicate the relationship between the various embodiments and / or settings discussed.

[0049] The term "and / or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, B exists alone, and A and B exist at the same time. The term " / and" in this article describes another type of association object relationship, indicating that there can be two relationships. For example, A / and B can mean: A exists alone, and A and B exist alone. In addition, the character " / " in this article generally indicates that the previous and next associated objects are in an "or" relationship.

[0050] It should also be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusions.

[0051] See also Figure 1-4 The present invention provides a technical solution for a thickness detection method for HVOF coating based on an energy dispersive X-ray fluorescence spectrometer: A thickness detection method for HVOF coating based on an energy dispersive X-ray fluorescence spectrometer, comprising the following steps:

[0052] S1: Conduct qualitative analysis on the permeation layer; The specific steps for qualitative analysis of the S1 permeation layer are as follows:

[0053] S1.1: Qualitative analysis of different elements in the analysis results of the permeated layer;

[0054] S1.2: Determine whether there is an obvious gradient in the analysis results;

[0055] S1.1 includes:

[0056] S1.11: Aluminizing project - Ni nickel element qualitative analysis;

[0057] S1.12: Aluminizing project - qualitative analysis of chromium element;

[0058] S1.13: Aluminizing project - qualitative analysis of Nb niobium element.

[0059] The elements involved in the items in S1.1 are calculated and analyzed using the same method to obtain the equivalent attenuation diagram.

[0060] S2: Quantitative analysis of the permeation layer:

[0061] The specific steps for quantitative analysis of the S2 permeation layer are as follows:

[0062] S2.1: Mark the coatings, with the outer coating as f1, the transition layer as f2, and the substrate as f3:

[0063] S2.2: Calculate and obtain the accurate thickness of the outer coating f1;

[0064] S2.3: Calculate the thickness of the transition layer f2;

[0065] S2.4: Peel off the strength of other identical elements that distinguish the base material f3 and the transition layer f2.

[0066] In S2: Assume that the outer coating f1 and the transition layer f2 have the same element g, and the fluorescence intensity of this element detected by the energy dispersive X-ray fluorescence spectrometer is G I0 .

[0067] The calculation steps of S2.2 are as follows:

[0068] The relationship between the outer coating f1 and the transition layer f2 is as follows (assuming the thickness of the outer coating f1 is x): ax+be^-U 12 cX=d;

[0069] Where: abcd is a non-zero natural number, U12 is an absorption coefficient of the outer coating f1 and the transition diffusion layer f2;

[0070] By solving for the value of x, we obtain the exact thickness of the outer coating f1.

[0071] The calculation steps of S2.3 are as follows:

[0072] By formula: I = I o e^-μρdx

[0073] Where: I is the intensity of X-rays after attenuation, I 0 is the initial intensity of the incident X-ray, μ is the mass absorption coefficient of the material, ρ is the density of the material, and dx represents the thickness of the material;

[0074] Calculate the X-ray intensity I of the outer coating f1 occupied by element g 0 , and obtain the X-ray intensity G of the same element g in the transition layer f2 I0 -I 0 :

[0075] Finally, the thickness of the transition layer f2 is calculated.

[0076] Figure 5 This is a comparison chart of the uncorrected penetration layer data in the present invention, with a maximum deviation of 27.10 um.

[0077] Figure 6 This is a comparison chart of the corrected penetration layer data in the present invention, with a maximum deviation of 10.33 um.

[0078] When used specifically, a qualitative analysis of the penetration layer is first performed, and then a qualitative analysis of the nickel element of the aluminizing project-Ni; a qualitative analysis of the chromium element of the aluminizing project-Cr; and a qualitative analysis of the niobium element of the aluminizing project-Nb. The attenuation effect of the chromium element is obviously better, and there is an obvious gradient change of the transition penetration layer from the 10th to the 13th time. Then a quantitative analysis of the penetration layer is performed, and finally the thickness of the transition penetration layer f2 is calculated through step S2.

[0079] The above description is only the preferred embodiment of the present invention, which does not limit the protection scope of the present invention. For those skilled in the art, the present invention can be modified and varied in various ways. Within the spirit and principle of the present invention, any change, modification, replacement, integration and parameter change of these embodiments by conventional substitution or capable of achieving the same function without departing from the principle and spirit of the present invention shall fall within the protection scope of the present invention.

Claims

1. A method for measuring the thickness of HVOF coating based on energy dispersive X-ray fluorescence spectrometer, characterized in that: The following steps are involved: S1: Qualitative analysis of the permeate layer; S2: Quantitative analysis of the infiltration layer.

2. The method for measuring the thickness of HVOF coating based on energy dispersive X-ray fluorescence spectrometer according to claim 1, characterized in that: The specific steps for qualitative analysis of the S1 permeation layer are as follows: S1.1: Qualitative analysis of different elements in the analysis results of the permeated layer; S1.2: Determine whether there is an obvious gradient in the analysis results.

3. The method for measuring the thickness of HVOF coating based on energy dispersive X-ray fluorescence spectrometer according to claim 2, characterized in that: The S1.1 includes: S1.11: Aluminizing project - Ni element qualitative analysis; S1.12: Aluminizing project - qualitative analysis of chromium element; S1.13: Aluminizing project - qualitative analysis of niobium element Nb.

4. The method for measuring the thickness of HVOF coating based on energy dispersive X-ray fluorescence spectrometer according to claim 3, characterized in that: The elements involved in the S1.1 item are calculated and analyzed using the same method to obtain the equivalent attenuation diagram.

5. The method for measuring the thickness of HVOF coating based on energy dispersive X-ray fluorescence spectrometer according to claim 4, characterized in that: The specific steps of the quantitative analysis of the S2 permeation layer are as follows: S2.1: Mark the coatings, with the outer coating as f1, the transition layer as f2, and the substrate as f3: S2.2: Calculate and obtain the accurate thickness of the outer coating f1; S2.3: Calculate the thickness of the transition layer f2; S2.4: Peel off the strength of other identical elements that distinguish the base material f3 and the transition layer f2.

6. The method for measuring the thickness of HVOF coating based on energy dispersive X-ray fluorescence spectrometer according to claim 5, characterized in that: In S2, it is assumed that the outer coating layer f1 and the transition layer f2 have the same element g, and the fluorescence intensity of the element detected by the energy dispersive X-ray fluorescence spectrometer is G I0 .

7. The method for measuring the thickness of HVOF coating based on energy dispersive X-ray fluorescence spectrometer according to claim 6, characterized in that: The calculation steps of S2.2 are as follows: The relationship between the outer coating f1 and the transition layer f2 is as follows (assuming the thickness of the outer coating f1 is x): ax+be^-U 12 cX=d; Where: abcd is a non-zero natural number, U12 is an absorption coefficient of the outer coating f1 and the transition diffusion layer f2; By solving for the value of x, the exact thickness of the outer coating f1 is obtained.

8. The method for measuring the thickness of HVOF coating based on energy dispersive X-ray fluorescence spectrometer according to claim 7, characterized in that: The calculation steps of S2.3 are as follows: By formula: I = I o e^-μρdx Where: I is the intensity of the attenuated X-ray, I0 is the initial intensity of the incident X-ray, μ is the mass absorption coefficient of the material, ρ is the density of the material, and dx represents the thickness of the material; Calculate the X-ray intensity I0 of the element g in the outer coating f1, and obtain the X-ray intensity G of the same element g in the transition layer f2 I0 -I0: Finally, the thickness of the transition layer f2 is calculated.

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