Method for detecting content of niobium element in iron-nickel-based superalloy

Abstract

The invention provides a method for detecting the content of a niobium element in an iron-nickel-based superalloy, and belongs to the technical field of component detection. The technical problem that the niobium element content in the iron-nickel-based superalloy is not accurately detected is solved. According to the detection method, firstly, the iron-nickel-based high-temperature alloy is pretreated, then perchloric acid smoking treatment is conducted, then under the heating condition, tartaric acid is complexed with vanadium and tungsten, EDTA is complexed with zirconium, so that impurity ion interference is eliminated, finally, niobium and chlorosulfonated phenol S generate a dark blue complex in a hydrochloric acid medium, the complex has remarkable light absorption, and the detection sensitivity is high. The content of the niobium element can be detected by using spectrophotometry; meanwhile, acetone in the chromogenic reaction is beneficial to protonation of the color developing agent, reduces and stabilizes absorption of a reagent background, and has a solubilizing effect on the reaction on the other hand. The detection method provided by the invention is suitable for detecting the niobium element in the iron-nickel-based superalloy, and is high in sensitivity and accuracy and simple to operate.

Description

Technical Field

[0001] The invention belongs to the technical field of component detection, and particularly relates to a method for detecting the content of niobium element in an iron-nickel based high temperature alloy. Background Art

[0002] Iron-nickel-based superalloy is an important material widely used in aviation, aerospace, energy, chemical industry and other fields. Among them, niobium (Nb) as an important alloying element has a significant impact on the performance of iron-nickel-based superalloy. Therefore, accurate determination of the content of niobium in iron-nickel-based superalloy is of great significance for material quality control, performance evaluation and new material research and development. At present, the main methods for detecting the content of niobium in iron-nickel-based superalloy are inductively coupled plasma optical emission spectrometry (ICP-OES), inductively coupled plasma mass spectrometry (ICP-MS) and X-ray fluorescence spectrometry (XRF). ICP-OES and ICP-MS may be affected by the spectral interference of other elements (such as tungsten, tantalum, etc.) during the analysis process, affecting the accurate determination of niobium. ICP-MS may also be affected by background noise and matrix effect, thus affecting the accurate determination of niobium. The sensitivity of XRF method is low, and it is impossible to accurately determine the trace niobium in iron-nickel-based superalloy. At the same time, this method is greatly affected by the surface state of the sample (such as roughness, oxide layer, etc.), which will lead to inaccurate determination of niobium. Summary of the invention

[0003] In order to solve the technical problem of inaccurate detection of niobium content in an iron-nickel-based high-temperature alloy, the present invention provides a method for detecting the niobium content in an iron-nickel-based high-temperature alloy.

[0004] The purpose of the present invention is achieved through the following technical solutions:

[0005] The object of the present invention is to provide a method for detecting the content of niobium in an iron-nickel-based high-temperature alloy, comprising:

[0006] (1) Sample dissolution and oxidation: Weigh 0.2000 g of the sample to be tested and place it in a conical flask, add a mixed acid, and dissolve the sample to be tested at a certain temperature. After the dissolution is completed, add perchloric acid to perform a fume treatment, and then cool to obtain a test solution;

[0007] (2) Preparation of mother solution: Add 20 mL of tartaric acid solution to the test solution for the first boiling. After cooling for 1 min, add 5 mL of hydrochloric acid solution and 20 mL of deionized water. Boil again until the test solution is clear and transparent. Cool, place in a 50 mL volumetric flask, make up to volume with deionized water, and shake well to obtain a mother solution.

[0008] (3) Preparation of color developing solution and blank solution: 5 mL of the mother solution was taken and placed in a 50 mL volumetric flask, 5 mL of ethylenediaminetetraacetic acid solution, 10 mL of hydrochloric acid solution, 5 mL of acetone and 5 mL of chlorosulfonphenol S solution were added, the volume was made up with deionized water, the mixture was shaken and allowed to stand to obtain a color developing solution;

[0009] 5 mL of the mother solution was placed in a 50 mL volumetric flask, and 5 mL of ethylenediaminetetraacetic acid solution, 10 mL of hydrochloric acid solution, 5 mL of acetone, 1 mL of hydrofluoric acid solution, and 5 mL of chlorosulfonphenol S solution were added. The volume was adjusted with deionized water, and the mixture was shaken and allowed to stand under the same conditions as the color developing solution to obtain a blank solution.

[0010] (4) Preparation of standard working curve and sample determination: 0, 0.10, 0.20, 0.40, 0.60 and 0.80 mL of 0.002 mg / mL niobium standard solution were placed in 6 50 mL volumetric flasks respectively. 5 mL of mother solution was transferred to each of the 6 volumetric flasks. Then, 5 mL of ethylenediaminetetraacetic acid solution, 10 mL of hydrochloric acid solution, 5 mL of acetone and 5 mL of chlorosulfonphenol S solution were added to each of the 6 volumetric flasks. The flasks were made up to volume with deionized water, shaken and allowed to stand under the same conditions as the color developing solution in (3). The UV spectrophotometer was preheated and zeroed at 650 nm using the standard 0 point. The absorbance of the standard solution and the sample solution to be tested was measured to obtain a standard working curve. The niobium content was found from the standard working curve.

[0011] It is further defined that the mixed acid in (1) is composed of hydrochloric acid, nitric acid and hydrofluoric acid in a volume ratio of 8:4:1.

[0012] It is further defined that the volume mass ratio of the mixed acid to the iron-nickel based high temperature alloy in (1) is 20 mL: 0.2000 g.

[0013] It is further defined that the dissolution temperature in (1) is 150-200°C.

[0014] It is further defined that the smoke treatment temperature in (1) is 300-350°C and the time is 5-10 minutes.

[0015] It is further defined that the concentration of the tartaric acid solution in (2) is 30 wt %.

[0016] It is further defined that the first boiling temperature in (2) is 150-200° C. and the time is 1-2 min.

[0017] It is further defined that the second boiling temperature in (2) is 150-200°C.

[0018] It is further defined that in (3), the concentration of the EDTA solution is 1 wt %, and the concentration of the chlorosulfonphenol S solution is 0.05 wt %.

[0019] It is further defined that the color developing solution in (3) is allowed to stand at a temperature of 15 to 30°C for a period of 30 to 40 minutes.

[0020] The beneficial effects achieved by the present invention are as follows:

[0021] The present invention first pre-treats the iron-nickel-based high-temperature alloy, then performs a perchloric acid fume treatment, and then under heating conditions, tartaric acid complexes with vanadium and tungsten to eliminate interference from vanadium and tungsten impurity ions, and ethylenediaminetetraacetic acid (EDTA) complexes with zirconium and other interfering elements to eliminate interference, and then niobium ions and chlorosulfonphenol S undergo a complex reaction (i.e., a color reaction) in a hydrochloric acid medium to generate a stable 1:1 blue-green niobium-chlorosulfonphenol S complex, which has significant absorbance, especially at a wavelength of 650nm, so that the niobium element content can be detected by photometry, and the detection result is highly accurate. Compared with the prior art, the present invention also has the following advantages:

[0022] (1) The conventional fume treatment uses sulfuric acid to treat the sample, which will cause the metal components in the iron-nickel-based high-temperature alloy to precipitate in the form of salts. The sample is not fully dissolved, which affects the accuracy of the final niobium content determination. The present invention uses perchloric acid to perform fume treatment on the sample, optimizes the pretreatment process, no elements are precipitated in the iron-nickel-based high-temperature alloy, and the sample is fully dissolved, ensuring the accuracy of the niobium content detection.

[0023] (2) The detection method provided by the present invention introduces tartaric acid. In a solution containing vanadium and tungsten, tartaric acid will react with vanadium and tungsten ions to form stable tartrate vanadium complexes and tartrate tungsten complexes. The formation of these complexes reduces the chances of vanadium and tungsten ions reacting with chlorosulfonphenol S, thereby reducing interference with the determination of niobium content. At the same time, since the complex reaction of tartaric acid with vanadium and tungsten has high selectivity, it can effectively remove or reduce the interference of vanadium and tungsten without interfering with the determination of niobium, which makes it possible to more accurately determine the niobium content in iron-nickel-based high-temperature alloys by photometry using chlorosulfonphenol S.

[0024] (3) The detection method provided by the present invention introduces EDTA. EDTA can react with impurity ions such as tungsten and molybdenum to form a stable tungsten-ethylenediaminetetraacetic acid complex or molybdenum-ethylenediaminetetraacetic acid complex. The coordination reaction of EDTA with impurity ions has high selectivity and can preferentially react with interfering ions such as tungsten and molybdenum, thereby protecting the complex reaction of niobium ions and chlorosulfonphenol S from interference.

[0025] (4) The detection method provided by the present invention introduces acetone. As an organic solvent, acetone helps to increase the solubility of the complex in the color development reaction system of niobium ions and chlorosulfonphenol S, so that it can be better dispersed in the reaction medium. This solubilization effect helps to improve the uniformity and stability of the color development reaction. At the same time, the presence of acetone also helps to reduce and stabilize the background absorption of the reagent (chlorosulfonphenol S), thereby reducing interference and improving the accuracy of niobium detection. Therefore, acetone optimizes the color development reaction conditions by solubilizing and stabilizing the background absorption of the reagent, thereby comprehensively improving the accuracy of the determination of niobium content.

[0026] (5) The detection method provided by the present invention is cost-effective. The instruments and equipment used in the present invention are simple, the equipment price and maintenance cost are low, the reagent consumption is small, and most of them are conventional reagents that are easy to obtain. The operation steps are simple, the operation cost is low, and it is easy to popularize and apply.

[0027] (6) The detection method provided by the present invention has good selectivity. The present invention is based on the specific color development reaction of chlorosulfonphenol S and niobium, and has good selectivity for niobium. By adjusting the test conditions, the interference of other impurity elements can be further reduced, and the detection accuracy of niobium can be improved. Although methods such as ICP-OES, ICP-MS and XRF can simultaneously determine multiple elements, when determining a specific element, it will be interfered by other coexisting elements, resulting in low accuracy of the test results.

[0028] (7) The detection method provided by the present invention is highly flexible. The detection conditions of the present invention are easy to adjust and can be optimized according to the characteristics of different iron-nickel-based high-temperature alloy samples, thereby improving the accuracy and sensitivity of niobium element determination, being applicable to different types of iron-nickel-based high-temperature alloy samples and having a wide range of applications.

[0029] (8) The detection method provided by the present invention has strong environmental adaptability. The present invention can perform color development reaction and niobium element determination at room temperature, without the need for special heating or cooling equipment, and is applicable to a variety of environmental conditions. In addition, the reagents used are stable and not easily affected by environmental factors, thus ensuring the stability and reliability of niobium element determination. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is the standard curve in Example 1. DETAILED DESCRIPTION

[0031] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in combination with the embodiments of the specification. In the following description, many specific details are elaborated to facilitate a full understanding of the present invention, but the present invention can also be implemented in other ways different from those described herein. Those skilled in the art can make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0032] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0033] The experimental methods used in the following examples are conventional methods unless otherwise specified. The materials, reagents, methods and instruments used are conventional materials, reagents, methods and instruments in the art unless otherwise specified, and can be obtained through commercial channels by those skilled in the art.

[0034] Reagents used in the following examples: water is deionized water or distilled water; hydrochloric acid concentration is 1.19 g / mL; nitric acid concentration is 1.42 g / mL; hydrofluoric acid concentration is 1.15 g / mL; perchloric acid concentration is 1.76 g / mL; acetone concentration is 0.79 g / mL; hydrochloric acid solution: a hydrochloric acid solution (1+1) obtained by mixing equal volumes of hydrochloric acid with a concentration of 1.19 g / mL and water; hydrofluoric acid solution: a hydrofluoric acid solution (1+6) obtained by mixing hydrofluoric acid with a concentration of 1.15 g / mL and water in a volume ratio of 1:6; tartaric acid, ethylenediaminetetraacetic acid, and chlorosulfonphenol S are all analytically pure reagents.

[0035] In order to verify the accuracy of the detection method provided by the present invention, the niobium content of different traceable certified metal standards was detected. The specific detection method is shown in Examples 1 to 5.

[0036] Example 1

[0037] (1) Sample dissolution and oxidation: Weigh 0.2000 g of certified metal standard YSBC 11589-2020 into a 100 mL conical flask, add 20 mL of a mixed acid consisting of hydrochloric acid, nitric acid and hydrofluoric acid in a volume ratio of 8:4:1, dissolve the certified metal standard YSBC 11589-2020 completely at 200 °C, then add 5 mL of perchloric acid, heat at 300 °C to evaporate and smoke for 5 to 10 min, until it is completely dry, remove and cool slightly;

[0038] (2) Preparation of mother solution: add 20 mL of 30 wt % tartaric acid solution to the slightly cooled test solution, heat and boil at 200° C. for 1 min, cool for 1 min (slightly cool), add 5 mL of hydrochloric acid solution (1+1) (prepared by mixing equal volumes of hydrochloric acid with a concentration of 1.19 g / mL and water) and 20 mL of deionized water, then heat and boil again at 200° C. until the solution is clear and transparent, cool, place the solution in a 50 mL volumetric flask, make up to volume with deionized water, and shake well to obtain a mother solution;

[0039] (3) Preparation of color developing solution and blank solution:

[0040] Color developing solution: Accurately pipette 5 mL of mother solution into a 50 mL volumetric flask, add 5 mL of EDTA solution (1 wt%), 10 mL of hydrochloric acid solution (1+1), 5 mL of acetone and 5 mL of chlorosulfonphenol S solution (0.05 wt%), dilute to volume with deionized water, shake well, and place at room temperature for 30 min. The room temperature should be kept at 15-30 °C.

[0041] Blank solution: Accurately pipette 5 mL of mother solution into a 50 mL volumetric flask, add 5 mL of EDTA solution (1 wt%), 10 mL of hydrochloric acid solution (1+1), 5 mL of acetone, 1 mL of hydrofluoric acid (1+6) (1.15 g / mL hydrofluoric acid mixed with water in a volume ratio of 1:6) and 5 mL of chlorosulfonphenol S solution (0.05 wt%), make up to volume with deionized water, shake well, and place it together with the color developing solution at room temperature for 30 min. The room temperature should be kept at 15-30 °C.

[0042] (4) Drawing of standard working curve and sample determination: 0, 0.10, 0.20, 0.40, 0.60 and 0.80 mL of 0.002 mg / mL niobium standard solution were placed in 6 50 mL volumetric flasks respectively. 5 mL of mother solution was added to each of the 6 volumetric flasks. Then, 5 mL of ETA solution, 10 mL of hydrochloric acid solution (1+1), 5 mL of acetone and 5 mL of chlorosulfonphenol S solution were added to each of the 6 volumetric flasks. The solution was fixed to volume with deionized water, shaken well and placed together with the color developing solution at room temperature for 30 min. The room temperature was ensured to be between 15 and 30 °C. The UV spectrophotometer was preheated for 40 min and zeroed at 650 nm using the standard 0 point. The absorbance of the standard solution was determined. The standard working curve was drawn with the mass fraction of niobium as the horizontal axis and the absorbance as the vertical axis, as shown in the following figure: Figure 1 As shown, the correlation coefficient of the standard working curve is greater than 0.999, and then the absorbance of the sample solution to be tested is measured, and the niobium content in the sample solution to be tested is found out from the standard working curve.

[0043] The test results of the niobium content in the certified metal standard YSBC 11589-2020 in this example are shown in Table 1.

[0044] Example 2

[0045] The difference between this embodiment and embodiment 1 is that the sample is the certified metal standard sample YSBC 11529-2020, and the remaining steps and process parameters are the same. The detection results of the niobium content in the certified metal standard sample YSBC 11529-2020 in this embodiment are shown in Table 1.

[0046] Example 3

[0047] The difference between this embodiment and embodiment 1 is that the sample is the certified metal standard sample IARM 5013, and the remaining steps and process parameters are the same. The detection results of the niobium content in the certified metal standard sample IARM 5013 in this embodiment are shown in Table 1.

[0048] Example 4

[0049] The difference between this embodiment and embodiment 1 is that the sample is a certified metal standard sample BS 500D, and the remaining steps and process parameters are the same. The detection results of the niobium content in the certified metal standard sample BS 500D of this embodiment are shown in Table 1.

[0050] Example 5

[0051] The difference between this embodiment and embodiment 1 is that the sample is a certified metal standard sample 23X 08811A, and the remaining steps and process parameters are the same. The detection results of the niobium content in the certified metal standard sample 23X 08811A in this embodiment are shown in Table 1.

[0052] In order to further verify the accuracy of the detection method provided by the present invention, the niobium content of the certified metal standards in Examples 1 to 5 was detected by ICP-AES, ICP-MS and XRF methods respectively. The results are detailed in Table 1.

[0053] Table 1 Detection results of niobium content in certified metal standard samples of Examples 1 to 5

[0054]

[0055]

[0056] It can be seen from the data in Table 1 that when the samples to be tested are of the same mass, the content of niobium in the samples can be detected and is within the uncertainty range of the certified metal standard; the niobium content detected by ICP-AES, ICP-MS and XRF methods is significantly different from the standard value, which is not as close to the standard value as the detection method provided by the present invention, indicating that the detection method provided by the present invention has higher accuracy and reliability than the traditional method.

[0057] The detection method provided by the present invention is used to detect the niobium content in different iron-nickel-based high-temperature alloys (numbered 1 to 7), and ICP-AES, ICP-MS and XRF methods are also used for detection.

[0058] Example 6

[0059] The difference between this embodiment and embodiment 1 is that the sample is an iron-nickel-based high-temperature alloy 1, and the steps and process parameters are the same. The detection results of the niobium element content in the iron-nickel-based high-temperature alloy 1 in this embodiment are shown in Table 2.

[0060] Example 7

[0061] The difference between this embodiment and embodiment 1 is that the sample is an iron-nickel-based high-temperature alloy 2, and the steps and process parameters are the same. The detection results of the niobium element content in the iron-nickel-based high-temperature alloy 2 in this embodiment are shown in Table 2.

[0062] Example 8

[0063] The difference between this embodiment and embodiment 1 is that the sample is an iron-nickel-based high-temperature alloy 3, and the steps and process parameters are the same. The detection results of the niobium element content in the iron-nickel-based high-temperature alloy 3 in this embodiment are shown in Table 2.

[0064] Example 9

[0065] The difference between this embodiment and embodiment 1 is that the sample is an iron-nickel-based high-temperature alloy 4, and the steps and process parameters are the same. The detection results of the niobium element content in the iron-nickel-based high-temperature alloy 4 in this embodiment are shown in Table 2.

[0066] Example 10

[0067] The difference between this embodiment and embodiment 1 is that the sample is an iron-nickel-based high-temperature alloy 5, and the steps and process parameters are the same. The detection results of the niobium element content in the iron-nickel-based high-temperature alloy 5 in this embodiment are shown in Table 2.

[0068] Embodiment 11

[0069] The difference between this embodiment and embodiment 1 is that the sample is an iron-nickel-based high-temperature alloy 6, and the steps and process parameters are the same. The detection results of the niobium element content in the iron-nickel-based high-temperature alloy 6 in this embodiment are shown in Table 2.

[0070] Example 12

[0071] The difference between this embodiment and embodiment 1 is that the sample is an iron-nickel-based high-temperature alloy 7, and the steps and process parameters are the same. The detection results of the niobium element content in the iron-nickel-based high-temperature alloy 7 in this embodiment are shown in Table 2.

[0072] The niobium content of the iron-nickel-based high-temperature alloys in Examples 6 to 12 was detected by ICP-AES, ICP-MS and XRF methods, respectively. The results are shown in Table 2.

[0073] Table 2 Detection results of niobium content in the iron-nickel-based high-temperature alloys of Examples 6 to 12 by ICP-AES, ICP-MS, XRF and the photometric method provided by the present invention

[0074]

[0075] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for detecting the niobium content in an iron-nickel-based high-temperature alloy, characterized in that: include: (1) Sample dissolution and oxidation: Weigh 0.2000 g of the sample to be tested and place it in a conical flask, add a mixed acid, and dissolve the sample to be tested at a certain temperature. After the dissolution is completed, add perchloric acid to perform a fume treatment, and then cool to obtain a test solution; (2) Preparation of mother solution: Add 20 mL of tartaric acid solution to the test solution for the first boiling. After cooling for 1 min, add 5 mL of hydrochloric acid solution and 20 mL of deionized water. Boil again until the test solution is clear and transparent. Cool, place in a 50 mL volumetric flask, make up to volume with deionized water, and shake well to obtain a mother solution. (3) Preparation of color developing solution and blank solution: 5 mL of the mother solution was taken and placed in a 50 mL volumetric flask, 5 mL of ethylenediaminetetraacetic acid solution, 10 mL of hydrochloric acid solution, 5 mL of acetone and 5 mL of chlorosulfonphenol S solution were added, the volume was made up with deionized water, the mixture was shaken and allowed to stand to obtain a color developing solution; 5 mL of the mother solution was placed in a 50 mL volumetric flask, and 5 mL of ethylenediaminetetraacetic acid solution, 10 mL of hydrochloric acid solution, 5 mL of acetone, 1 mL of hydrofluoric acid solution, and 5 mL of chlorosulfonphenol S solution were added. The volume was adjusted with deionized water, and the mixture was shaken and allowed to stand under the same conditions as the color developing solution to obtain a blank solution. (4) Preparation of standard working curve and sample determination: 0, 0.10, 0.20, 0.40, 0.60 and 0.80 mL of 0.002 mg / mL niobium standard solution were placed in 6 50 mL volumetric flasks respectively. 5 mL of mother solution was transferred to each of the 6 volumetric flasks. Then, 5 mL of ethylenediaminetetraacetic acid solution, 10 mL of hydrochloric acid solution, 5 mL of acetone and 5 mL of chlorosulfonphenol S solution were added to each of the 6 volumetric flasks. The flasks were made up to volume with deionized water, shaken and allowed to stand under the same conditions as the color developing solution in (3). The UV spectrophotometer was preheated and zeroed at 650 nm using the standard 0 point. The absorbance of the standard solution and the sample solution to be tested was measured to obtain a standard working curve. The niobium content was found from the standard working curve.

2. The detection method according to claim 1, characterized in that: (1) The mixed acid is composed of hydrochloric acid, nitric acid and hydrofluoric acid in a volume ratio of 8:4:

1.

3. The detection method according to claim 1, characterized in that: (1) The volume mass ratio of the mixed acid to the iron-nickel based high temperature alloy is 20 mL: 0.2000 g.

4. The detection method according to claim 1, characterized in that: (1) The dissolution temperature is 150-200°C.

5. The detection method according to claim 1, characterized in that: (1) The temperature of the medium smoke treatment is 300-350°C and the time is 5-10 minutes.

6. The detection method according to claim 1, characterized in that: (2) The concentration of tartaric acid solution is 30 wt%.

7. The detection method according to claim 1, characterized in that: (2) The first boiling temperature is 150-200°C and the time is 1-2 minutes.

8. The detection method according to claim 1, characterized in that: (2) The second boiling temperature is 150-200°C.

9. The detection method according to claim 1, characterized in that: (3) The concentration of EDTA solution is 1 wt % and the concentration of chlorosulfonphenol S solution is 0.05 wt %.

10. The detection method according to claim 1, characterized in that: (3) The color developing solution is allowed to stand at a temperature of 15 to 30°C for 30 to 40 minutes.

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