Observation and Analysis Method for Inhibiting Layer of Multielement Alloy Coating on Hot-Dip Galvanized Substrate

Abstract

The present invention relates to the technical field of iron and steel metallurgy, and discloses a method for observing and analyzing an inhibition layer of a hot-dip galvanized multi-element alloy coating, comprising the following steps: A) specimen preparation; B) preparation of a dezincification agent; C) dezincification of an alloy-coated steel plate; D) preparation of a carbon film sample of the alloy-coated inhibition layer; E) scanning electron microscope analysis. The method for observing and analyzing the inhibition layer of the hot-dip galvanized multi-element alloy coating of the present invention can exclude the influence of the coating and the substrate, and relatively accurately determine the elemental composition and phase structure of the inhibition layer.

Description

Technical Field

[0001] The present invention relates to the technical field of hot-dip galvanization, and particularly relates to a method for observing and analyzing an inhibition layer of a multi-element alloy coating based on hot-dip galvanization. Background Art

[0002] Hot-dip galvanizing, also known as hot-dip zinc plating and hot-dip galvanization, is an effective method for metal anti-corrosion. It is the most economical and effective surface treatment method to prevent steel from corroding in the natural environment and is widely used in the protection of various structures of steel materials. During the production of hot-dip galvanized sheets with pure zinc coatings, an appropriate amount of aluminum is often added to the zinc bath to form a thin Fe-Al compound layer between the steel substrate and the zinc coating, so as to inhibit the diffusion reaction between zinc and iron and improve the coating performance. This Fe-Al compound layer is called the inhibition layer. The inhibition layer plays a crucial role in the coating quality and structure of hot-dip galvanized sheets, and many defects on the surface of hot-dip galvanized sheets are closely related to the inhibition layer. At present, there has been sufficient research on the inhibition layer of pure zinc coatings, and it is generally believed in the industry that it is the Fe2Al5 phase.

[0003] With the development of hot-dip galvanization technology, more and more zinc-based multi-element alloy coatings have been developed and applied, which generally add various metal elements on the basis of pure zinc coatings. For example, zinc-aluminum-magnesium coatings are added with certain proportions of elements such as aluminum and magnesium on the basis of pure zinc coatings. In addition, silicon, titanium, copper, boron, etc. are also common additive elements. Due to the addition of other elements, the inhibition layer of the multi-element alloy coating is no longer a single Fe2Al5 phase structure containing iron and aluminum elements, and its specific composition is closely related to the added alloy elements. If a similar method for observing the cross-section or surface corrosion of the inhibition layer of pure zinc coatings is used, due to the interference of elements in the substrate and the coating, it is impossible to accurately determine the element composition and phase structure of the inhibition layer.

[0004] Chinese Patent (Publication Date: December 11, 2013, Publication Number: CN103439170A) discloses a method for displaying and detecting the inhibition layer of hot-dip galvanized sheets. The technical solution adopted is: using a hot-dip galvanized sheet sample as the anode, a platinum electrode as the auxiliary electrode, and a saturated calomel electrode as the reference electrode. In a sodium chloride-hydrochloric acid electrolyte, constant potential electrolysis is carried out within the potential range of -1.030V to -0.980V relative to the saturated calomel electrode to dissolve the pure zinc layer; record the current-time curve during the electrolysis process. When the electrolysis current decreases to zero, the pure zinc layer is completely dissolved, and the reaction is stopped at this time; take out the sample, wash it successively with deionized water and acetone, and observe and detect the inhibition layer with a scanning electron microscope after drying. Its advantage is that it can accurately control the experimental process and completely retain and display the inhibition layer while electrolytically removing the pure zinc layer. However, this method is mainly applied to the preparation of samples for observing the inhibition layer and cannot accurately measure the elements and phase structure of the inhibition layer.

[0005] Chinese Patent (Publication Date: November 23, 2018, Publication Number: CN108872285A) discloses a method for characterizing the inhibition layer of galvanized sheets. The method includes: obtaining a pretreated sample, which consists of a steel substrate and an Fe-Al inhibition layer in contact with the steel substrate; performing X-ray photoelectron spectroscopy (XPS) testing on the obtained pretreated sample. In the present invention, since the obtained pretreated sample only consists of a steel substrate and an Fe-Al inhibition layer in contact with the steel substrate, the analysis time can be effectively shortened and the analysis efficiency can be improved. Since this method uses X-ray photoelectron spectroscopy to test the pretreated sample, the changes of Fe, Zn, and Al elements in the inhibition layer with depth can be effectively measured, thereby inferring the formation quality of the inhibition layer, which is fast and accurate and can be used for the rapid quality determination of the inhibition layer of galvanized sheets. However, this method is mainly applied to the preparation of samples for observing the inhibition layer and is used for the rapid quality determination of the inhibition layer of galvanized sheets, and it cannot accurately measure the elemental composition and phase structure of the inhibition layer.

[0006] Chinese Patent (Publication Date: October 19, 2021, Publication Number: CN113514528A) discloses a method for measuring the compactness of the inhibition layer of hot-dip galvanized sheets. The method includes: obtaining a test sample of a hot-dip galvanized sheet; using the test sample of the hot-dip galvanized sheet as a working electrode, placing it together with an auxiliary electrode in an electrolyte, and applying a constant current polarization by applying an electric current to the working electrode and the auxiliary electrode; during the polarization process, record the polarization curve with the polarization time as the abscissa and the polarization voltage corresponding to the polarization time as the ordinate; take the derivative of the polarization curve to obtain a derivative curve; and obtain the compactness of the inhibition layer of the test sample of the hot-dip galvanized sheet according to the derivative curve. However, this method is mainly applied to the preparation of samples for observing the inhibition layer and is used for the determination of the compactness of the inhibition layer of galvanized sheets, and it cannot accurately measure the elemental composition and phase structure of the inhibition layer.

[0007] Chinese Patent (Publication Date: April 12, 2022, Publication Number: CN108872285A) discloses a corrosion solution for removing the galvanized layer of steel sheets and a method for revealing the inhibition layer of galvanized steel sheets. The method includes: the composition and mass fraction of the corrosion solution are: 70 parts of deionized water, 5 - 10 parts of saturated hydrochloric acid, 2 - 3 parts of hexamethylenetetramine, 1 - 2 parts of sodium nitrite, 0.1 - 0.15 parts of disodium ethylenediaminetetraacetate, and 0.05 - 0.10 parts of ammonium citrate. The method for revealing the inhibition layer of galvanized steel sheets: place the galvanized steel sheet in the above corrosion solution, take out the sample when the bubbles suddenly disappear, and place the corroded part of the steel sheet in alcohol. However, this method is mainly applied to the preparation of samples for observing the inhibition layer and cannot accurately measure the elemental composition and phase structure of the inhibition layer. Summary of the Invention

[0008] The object of the present invention is to address the deficiencies of the above-mentioned technology and provide an observation and analysis method for the inhibition layer of a hot-dip galvanized multi-alloy coating, which can exclude the influence of the coating and the substrate and relatively accurately determine the elemental composition and phase structure of the inhibition layer.

[0009] To achieve the above object, the observation and analysis method for the inhibition layer of a hot-dip galvanized multi-alloy coating designed by the present invention includes the following steps:

[0010] A) Specimen preparation: Cut the alloy-coated steel plate into appropriate sizes to obtain specimens.

[0011] B) Preparation of dezincification agent: Dissolve chromium trioxide and zinc sulfate heptahydrate in deionized water sufficiently to obtain a first solution, and then slowly add a nitric acid solution to the first solution to obtain a dezincification reagent.

[0012] C) Dezincification of the alloy-coated steel plate: Place the specimen prepared in step A) into the dezincification reagent prepared in step B). When the bubbles generated by the reaction are about to disappear, take out the specimen and place it in alcohol for ultrasonic cleaning. After the cleaning is completed, put the specimen back into the dezincification reagent. When the bubbles generated by the reaction are about to disappear, take out the specimen and place it in alcohol for ultrasonic cleaning. Repeat the operation until the black inhibition layer is exposed on the surface of the specimen after ultrasonic cleaning, and then dry it to complete the dezincification of the alloy-coated steel plate.

[0013] D) Preparation of a carbon film sample of the alloy coating inhibition layer: Use an ion sputtering carbon evaporation instrument to volatilize the carbon rod at a high temperature through the action of an electric current, and then deposit it on the surface of the specimen to form a carbon film. Then place the specimen in a dilute nitric acid solution until the carbon film on the surface of the specimen falls off. The fallen carbon film is the carbon film sample of the alloy coating inhibition layer.

[0014] E) Scanning electron microscope analysis: After cleaning the carbon film sample prepared in step D) with alcohol, place it on a tray and fix it with conductive glue. The tray is a single-conductive metal tray. Place the tray into a scanning electron microscope, and use the backscattered electron image of the scanning electron microscope to observe and qualitatively analyze the elemental and phase structure composition of the alloy coating inhibition layer in combination with an EDX energy spectrometer.

[0015] Preferably, in step B), the mass ratio of chromium trioxide to zinc sulfate heptahydrate is 4-6:1, the total mass of chromium trioxide and zinc sulfate heptahydrate added to 100 ml of deionized water is 20-30 grams, the mass fraction of the nitric acid solution is 65%-75%, and the volume ratio of the first solution to the nitric acid solution is 9-11:1.

[0016] Preferably, in step D), the carbon film is located on the dezincified surface of the specimen, the time for high-temperature volatilization and deposition of the carbon rod is 1-2 hours, and the mass fraction of the dilute nitric acid solution is 5%-15%.

[0017] The principle of the present invention is as follows: The alloy coating and the inhibition layer are separated using a dezincification reagent, and then a carbon film is deposited in the inhibition layer by the method of carbon volatilization deposition at high temperature. Finally, the alloy coating substrate and the inhibition layer protected by the carbon film are separated by the corrosion effect of nitric acid solution. The ultimate goal is to exclude the interference of the coating and substrate elements on the inhibition layer elements during scanning electron microscope analysis.

[0018] Compared with the prior art, the present invention has the following advantages: It can exclude the interference of the coating and substrate elements, and can relatively accurately determine the element composition and phase structure of the inhibition layer by observing with a scanning electron microscope. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a flow chart of the observation and analysis method for the inhibition layer of a hot-dip galvanized base multi-alloy coating of the present invention;

[0020] Figure 2 It is a carbon film diagram of the inhibition layer observed under a scanning electron microscope in Example 2;

[0021] Figure 3 It is the element composition and atomic ratio of the inhibition layer obtained by the EDX energy spectrum of the scanning electron microscope in Example 2. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] The present invention will be further described in detail below with reference to the drawings and specific embodiments.

[0023] Example 1

[0024] As Figure 1 shown, an observation and analysis method for the inhibition layer of a hot-dip galvanized base multi-alloy coating includes the following steps:

[0025] A) Specimen preparation: Cut the alloy-coated steel plate into appropriate sizes to obtain specimens;

[0026] B) Preparation of dezincification agent: Chromium trioxide and zinc sulfate heptahydrate are fully dissolved in deionized water to obtain a first solution, and then nitric acid solution is slowly added to the first solution to obtain a dezincification reagent;

[0027] C) Dezincification of the alloy-coated steel plate: The specimens prepared in step A are placed in the dezincification reagent prepared in step B). When the bubbles generated by the reaction are about to disappear, the specimens are taken out, placed in alcohol for ultrasonic cleaning. After the cleaning is completed, the specimens are placed in the dezincification reagent again. When the bubbles generated by the reaction are about to disappear, the specimens are taken out and placed in alcohol for ultrasonic cleaning. Repeat the operation until the black inhibition layer is exposed on the specimen surface after ultrasonic cleaning, and then dry it to complete the dezincification work of the alloy-coated steel plate;

[0028] D) Preparation of the carbon film sample for the alloy coating inhibition layer: Use an ion sputtering carbon evaporation instrument to volatilize the carbon rod at high temperature through the action of current, and then deposit it on the surface of the sample to form a carbon film. The carbon film is located on the dezincified surface of the sample. Then, place the sample in a dilute nitric acid solution until the carbon film on the surface of the sample falls off. The fallen carbon film is the carbon film sample for the alloy coating inhibition layer;

[0029] E) Scanning electron microscope analysis: After cleaning the carbon film sample prepared in step D) with alcohol, place it on a tray and fix it with conductive glue. The tray is a single conductive metal tray. Place the tray in a scanning electron microscope, and use the backscattered electron image of the scanning electron microscope to qualitatively analyze the elements and phase structure composition of the alloy coating inhibition layer in combination with the EDX energy spectrometer.

[0030] Example 2

[0031] A method for observing and analyzing the inhibition layer of a hot-dip galvanized-based multi-element alloy coating includes the following steps:

[0032] A) Specimen preparation: Cut an alloy coating steel plate with a thickness of 0.5 mm into specimens with a size of 1 * 1.5 mm. In this example, the alloy coating components are zinc, aluminum, magnesium, and trace copper, where the mass fraction of aluminum is 6%, the mass fraction of magnesium is 3%, there is also trace copper, and the rest is zinc;

[0033] B) Preparation of the dezincification agent: Dissolve 20 g of chromium trioxide and 4 g of zinc sulfate heptahydrate in 100 ml of deionized water to obtain a first solution. Then, slowly add 10 ml of a nitric acid solution with a mass fraction of 70% to the first solution to obtain the dezincification reagent;

[0034] C) Dezincification of the alloy coating steel plate: Place the specimen prepared in step A) into the dezincification reagent prepared in step B). When the bubbles generated by the reaction are about to disappear, take out the specimen and place it in alcohol for ultrasonic cleaning. After the cleaning is completed, place the specimen in the dezincification reagent again. When the bubbles generated by the reaction are about to disappear, take out the specimen and place it in alcohol for ultrasonic cleaning. Repeat the operation until the black inhibition layer is exposed on the surface of the specimen after ultrasonic cleaning, and then dry it to complete the dezincification work of the alloy coating steel plate;

[0035] D) Preparation of the carbon film sample for the alloy coating inhibition layer: Use an ion sputtering carbon evaporation instrument to volatilize the carbon rod at high temperature through the action of current, and then deposit it on the surface of the sample to form a carbon film. The carbon film is located on the dezincified surface of the sample. The time for the carbon rod to volatilize at high temperature and then deposit is 1.5 hours. Then, place the sample in a 10% dilute nitric acid solution by mass fraction until the carbon film on the surface of the sample falls off. The fallen carbon film is the carbon film sample for the alloy coating inhibition layer;

[0036] E) Scanning electron microscopy analysis: After the carbon film sample prepared in step D) is cleaned with alcohol, it is placed on a tray and fixed with conductive adhesive. The tray is a single conductive metal tray. The tray is placed in a scanning electron microscope, and the backscattered electron image of the scanning electron microscope is used to observe and qualitatively analyze the elemental and phase structure composition of the alloy coating inhibition layer by combining with an EDX energy spectrometer, such as Figure 2 and Figure 3 shown. In this embodiment, the inhibition layer is composed of Al, Fe, and Cu elements, and their atomic ratio is approximately 8:2:0.3.

[0037] Example 3

[0038] A method for observing and analyzing the inhibition layer of a hot-dip galvanized base multi-element alloy coating includes the following steps:

[0039] A) Specimen preparation: Cut an alloy coating steel plate with a thickness of 0.5 mm into specimens with a size of 1 * 1.5 mm. In this embodiment, the alloy coating components are zinc, aluminum, magnesium, and trace copper, where the mass fraction of aluminum is 5%, the mass fraction of magnesium is 4%, there is also trace copper, and the rest is zinc;

[0040] B) Preparation of dezincification agent: Dissolve 16 g of chromium trioxide and 4 g of zinc sulfate heptahydrate in 100 ml of deionized water to obtain a first solution, and then slowly add 11 ml of a 65% nitric acid solution by mass to the first solution to obtain a dezincification reagent;

[0041] C) Dezincification of the alloy coating steel plate: Put the specimen prepared in step A) into the dezincification reagent prepared in step B). When the bubbles generated by the reaction are about to disappear, take out the specimen and place it in alcohol for ultrasonic cleaning. After the cleaning is completed, put the specimen into the dezincification reagent again. When the bubbles generated by the reaction are about to disappear, take out the specimen and place it in alcohol for ultrasonic cleaning. Repeat the operation until the black inhibition layer is exposed on the surface of the specimen after ultrasonic cleaning, and then dry it to complete the dezincification work of the alloy coating steel plate;

[0042] D) Preparation of the carbon film sample of the alloy coating inhibition layer: Use an ion sputtering carbon evaporator to volatilize the carbon rod at high temperature through the action of current, and then deposit it on the surface of the specimen to form a carbon film. The carbon film is located on the dezincified surface of the specimen. The time for the carbon rod to volatilize at high temperature and then deposit is 1 hour. Then put the specimen into a 15% nitric acid solution by mass until the carbon film on the surface of the specimen falls off. The fallen carbon film is the carbon film sample of the alloy coating inhibition layer;

[0043] E) Scanning electron microscopy analysis: After the carbon film sample prepared in step D) is cleaned with alcohol, it is placed on a tray and fixed with conductive adhesive. The tray is a single conductive metal tray. The tray is placed in a scanning electron microscope, and the backscattered electron image of the scanning electron microscope is used to observe and qualitatively analyze the elemental and phase structure composition of the alloy coating inhibition layer.

[0044] Example 4

[0045] An observation and analysis method for an inhibition layer of a hot-dip galvanized multi-alloy coating, comprising the following steps:

[0046] A) Specimen preparation: Cut an alloy-coated steel plate with a thickness of 0.5 mm into specimens with a size of 1 * 1.5 mm. In this embodiment, the alloy coating components are zinc, aluminum, magnesium, and trace copper, where the mass fraction of aluminum is 7%, the mass fraction of magnesium is 2%, and there is also trace copper, and the rest is zinc;

[0047] B) Preparation of dezincification agent: Dissolve 24 g of chromium trioxide and 4 g of zinc sulfate heptahydrate in 100 ml of deionized water to obtain a first solution, and then slowly add 9 ml of a nitric acid solution with a mass fraction of 75% to the first solution to obtain a dezincification reagent;

[0048] C) Dezincification of the alloy-coated steel plate: Place the specimen prepared in step A) into the dezincification reagent prepared in step B). When the bubbles generated by the reaction are about to disappear, take out the specimen, place the specimen in alcohol for ultrasonic cleaning. After the cleaning is completed, put the specimen into the dezincification reagent again. When the bubbles generated by the reaction are about to disappear, take out the specimen, and place the specimen in alcohol for ultrasonic cleaning. Repeat the operation until the black inhibition layer is exposed on the surface of the specimen after ultrasonic cleaning, and then dry it to complete the dezincification of the alloy-coated steel plate;

[0049] D) Preparation of a carbon film sample of the alloy coating inhibition layer: Use an ion sputtering carbon evaporation instrument to volatilize the carbon rod at high temperature through the action of current, and then deposit it on the surface of the specimen to form a carbon film. The carbon film is located on the dezincified surface of the specimen. The time for the carbon rod to volatilize at high temperature and then deposit is 2 hours. Then, put the specimen into a dilute nitric acid solution with a mass fraction of 5% until the carbon film on the surface of the specimen falls off. The fallen carbon film is the carbon film sample of the alloy coating inhibition layer;

[0050] E) Scanning electron microscope analysis: After cleaning the carbon film sample prepared in step D) with alcohol, place it on a tray and fix it with conductive glue. The tray is a single conductive metal tray. Put the tray into the scanning electron microscope, and use the backscattered electron image of the scanning electron microscope to observe and qualitatively analyze the element and phase structure composition of the alloy coating inhibition layer by means of an EDX energy spectrometer.

[0051] Example 5

[0052] An observation and analysis method for an inhibition layer of a hot-dip galvanized multi-alloy coating, comprising the following steps:

[0053] A) Specimen preparation: Cut an alloy-coated steel plate with a thickness of 0.5 mm into specimens with a size of 1 * 1.5 mm. In this embodiment, the alloy coating components are zinc, aluminum, magnesium, and trace copper, where the mass fraction of aluminum is 6%, the mass fraction of magnesium is 4%, and there is also trace copper, and the rest is zinc;

[0054] B) Preparation of dezincification agent: Dissolve 25 g of chromium trioxide and 5 g of zinc sulfate heptahydrate in 100 ml of deionized water to obtain a first solution, and then slowly add 10 ml of a 70% nitric acid solution by mass to the first solution to obtain a dezincification reagent;

[0055] C) Dezincification of alloy-coated steel plate: Put the specimen prepared in step A into the dezincification reagent prepared in step B). When the bubbles generated by the reaction are about to disappear, take out the specimen, and place the specimen in alcohol for ultrasonic cleaning. After the cleaning is completed, put the specimen into the dezincification reagent again. When the bubbles generated by the reaction are about to disappear, take out the specimen, and place the specimen in alcohol for ultrasonic cleaning. Repeat the operation until the black inhibition layer is exposed on the surface of the specimen after ultrasonic cleaning, and then dry it to complete the dezincification of the alloy-coated steel plate;

[0056] D) Preparation of carbon film sample of alloy coating inhibition layer: Use an ion sputtering carbon evaporation instrument to volatilize the carbon rod at high temperature through the action of current, and then deposit it on the surface of the specimen to form a carbon film. The carbon film is located on the dezincified surface of the specimen. The time for the carbon rod to volatilize at high temperature and then deposit is 1.5 hours. Then put the specimen into a 10% nitric acid solution by mass until the carbon film on the surface of the specimen falls off. The fallen carbon film is the carbon film sample of the alloy coating inhibition layer;

[0057] E) Scanning electron microscope analysis: After the carbon film sample prepared in step D) is cleaned with alcohol, place it on a tray and fix it with conductive glue. The tray is a single conductive metal tray. Put the tray into the scanning electron microscope, and use the backscattered electron image of the scanning electron microscope to observe and qualitatively analyze the element and phase structure composition of the alloy coating inhibition layer with the help of an EDX energy spectrometer.

[0058] The observation and analysis method of the inhibition layer of the hot-dip galvanized multi-element alloy coating of the present invention uses a dezincification reagent to separate the alloy coating from the inhibition layer, and then deposits a carbon film on the inhibition layer by the method of carbon volatilization and deposition at high temperature. Finally, the alloy coating substrate and the inhibition layer protected by the carbon film are separated by the corrosion effect of the nitric acid solution. The ultimate goal is to exclude the interference of the coating and substrate elements on the inhibition layer elements during scanning electron microscope analysis, and to relatively accurately determine the element composition and phase structure of the inhibition layer.

Claims

1. An observation and analysis method for a multi-alloy coating inhibition layer on a hot-dip galvanized base, characterized in that: It includes the following steps: A) Specimen preparation: Cut the alloy-coated steel plate into appropriate sizes to obtain specimens; B) Preparation of dezincification agent: Dissolve chromium trioxide and zinc sulfate heptahydrate fully in deionized water to obtain a first solution, and then slowly add a nitric acid solution to the first solution to obtain a dezincification reagent. The mass ratio of chromium trioxide to zinc sulfate heptahydrate is 5:

1. The total mass of chromium trioxide and zinc sulfate heptahydrate added to 100 ml of deionized water is 30 grams. The mass fraction of the nitric acid solution is 70%, and the volume ratio of the first solution to the nitric acid solution is 10:1; C) Dezincification of alloy-coated steel plate: Put the specimen prepared in step A) into the dezincification reagent prepared in step B). When the bubbles generated by the reaction are about to disappear, take out the specimen and place the specimen in alcohol for ultrasonic cleaning. After the cleaning is completed, put the specimen into the dezincification reagent again. When the bubbles generated by the reaction are about to disappear, take out the specimen and place the specimen in alcohol for ultrasonic cleaning. Repeat the operation until the black inhibition layer is exposed on the surface of the specimen after ultrasonic cleaning. Dry it to complete the dezincification work of the alloy-coated steel plate; D) Preparation of carbon film sample of alloy-coated layer inhibition layer: Use an ion sputtering carbon evaporation instrument to volatilize the carbon rod at high temperature through the action of current, and then deposit it on the surface of the specimen to form a carbon film. Then put the specimen into a dilute nitric acid solution until the carbon film on the surface of the specimen falls off. The fallen carbon film is the carbon film sample of the alloy-coated layer inhibition layer. The carbon film is located on the dezincified surface of the specimen. The time for the carbon rod to volatilize at high temperature and then deposit is 1.5 hours. The mass fraction of the dilute nitric acid solution is 10%; E) Scanning electron microscope analysis: After the carbon film sample prepared in step D) is cleaned with alcohol, place it on a tray and fix it with conductive glue. The tray is a single conductive metal tray. Put the tray into the scanning electron microscope, and use the backscattered electron image of the scanning electron microscope to observe and qualitatively analyze the elements and phase structure composition of the alloy-coated layer inhibition layer in combination with the EDX energy spectrometer.

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