Chemical component analysis method of hafnium oxide modified silicon powder

Abstract

The invention belongs to the technical field of material science, and particularly relates to a chemical component analysis method of hafnium oxide modified silicon powder. Hydrofluoric acid and sulfuric acid are adopted as media, full dissolution of a sample is achieved by controlling the acid amount, the adding sequence, the temperature and the time, and interference of substrate silicon is eliminated through fuming. And selecting an analysis spectral line of a to-be-detected element through an element interference test, and preparing a standard solution curve to realize quantitative detection of a to-be-detected component. In the pretreatment process of the sample, the sample is completely dissolved, meanwhile, the influence of a matrix on a detection result is eliminated, the process of matching a standard curve solution with the matrix is omitted, and the established method for detecting the chemical components in the hafnium oxide modified silicon powder can be used for receiving a detection task and is accurate and reliable in detection result.

Description

Technical Field

[0001] The invention belongs to the technical field of material science, and in particular relates to a method for analyzing the chemical composition of hafnium oxide-modified silicon powder. Background Art

[0002] The chemical components that need to be tested for hafnium oxide modified silicon powder are mainly HfO2, Fe, Al, Ca, Cu, Cr, P, and B. f / SiC ceramic matrix composite material hot end components of the high temperature wearable sealing coating of the bottom layer of the spray material, this new material and other spray powder materials through the spray process to form a special wear-resistant, high temperature resistant functional coating, there is currently no mature chemical composition detection method in the industry for the quality control of hafnium oxide modified silicon powder. This project combines the characteristics of the sample to be tested to establish the corresponding sample pretreatment method, using inductively coupled plasma emission spectroscopy to solve the problem that hafnium oxide modified silicon powder materials cannot be independently detected.

[0003] The technical difficulty in analyzing this type of material is that hafnium oxide-modified silicon powder is prepared from hafnium oxide powder and silicon powder using a special process. Under normal conditions, the sample will quickly dissolve in a medium of hydrofluoric acid + nitric acid or sulfuric acid, and then form a large amount of precipitate that cannot be used for detection. Summary of the invention

[0004] In view of the problems in the prior art, the present invention provides a method for analyzing the chemical composition of hafnium oxide modified silicon powder, which can simultaneously measure multiple elements to be measured and solve the technical problems such as the difficulty in dissolving hafnium oxide modified silicon samples and substrate interference. The technical solution of the present invention is: A chemical composition analysis method for hafnium oxide modified silicon powder comprises the following steps: controlling the amount of acid, the order of addition, the temperature and the time to achieve complete dissolution of the hafnium oxide modified silicon powder sample, obtaining a clear sample solution, eliminating interference of matrix silicon by fuming, and making the sample solution meet the analysis requirements of an inductively coupled plasma emission spectrometer; preparing a standard solution without silicon primer according to the content range of the element to be measured in the sample, selecting the analysis spectrum of the element to be measured by an element interference test; establishing a working curve series solution, measuring the intensity of each element to be measured in the test solution on an inductively coupled plasma emission spectrometer under selected conditions, wherein the intensity is proportional to the content of the element to be measured, obtaining a working curve by linear fitting by a computer, and obtaining the mass fraction of each element from the working curve.

[0005] Furthermore, in the above-mentioned chemical composition analysis method of hafnium oxide modified silicon powder, the hafnium oxide modified silicon powder sample is placed in a 250mL polytetrafluoroethylene cup, the acid addition sequence of "sulfuric acid, hydrofluoric acid and nitric acid" is adopted, and it is placed on an electric furnace for heating to completely dissolve the hafnium oxide modified silicon powder sample, and heating is continued until a slight smoke is emitted, and the interference of matrix silicon is eliminated by the fuming of sulfuric acid; after cooling, it is diluted to a 100mL plastic volumetric flask at room temperature and shaken for testing.

[0006] Furthermore, in the above-mentioned chemical composition analysis method of hafnium oxide modified silicon powder, 0.1000 g of hafnium oxide modified silicon powder sample is weighed, 8 mL of sulfuric acid, 4 mL of hydrofluoric acid, and 1 mL of nitric acid are added.

[0007] Furthermore, in the above-mentioned method for analyzing the chemical composition of hafnium oxide-modified silicon powder, the electric furnace temperature is 150°C.

[0008] Furthermore, in the above-mentioned chemical composition analysis method of hafnium oxide modified silicon powder, 8 mL of 1:1 diluted sulfuric acid solution was added to multiple 100 mL plastic volumetric flasks respectively, and different amounts of Hf, Fe, Al, Ca, Cu, Cr, P, and B standard solutions were added according to the content range of the elements to be measured in the hafnium oxide modified silicon powder sample, and the solutions were diluted to the scale with water and shaken well to serve as the working curve series solutions, and the solutions without the elements to be measured were used as the "zero" concentration solutions in the working curve series solutions.

[0009] Furthermore, in the above-mentioned method for analyzing the chemical composition of hafnium oxide-modified silicon powder, at least three working curve series solutions are set in addition to the "zero" concentration solution.

[0010] Furthermore, in the above-mentioned method for analyzing the chemical composition of hafnium oxide-modified silicon powder, the working curve is set to require that the gradient covers the content range of the component to be tested.

[0011] Furthermore, the above-mentioned chemical composition analysis method of hafnium oxide modified silicon powder performs linear fitting according to the relationship between the spectral line intensity of each solution and the element content, and calculates the accurate content of the element to be measured, wherein hafnium oxide is converted by the hafnium content, and the conversion coefficient is 1.18. The formula for calculating the content of the element to be measured (M) is: M(%)=kI+b, wherein: k—represents the slope of the calibration curve; b—intercept of the working curve; I—measured signal intensity of the element to be measured.

[0012] Advantages and beneficial effects of the present invention: In the process of sample pretreatment, the present invention not only completely dissolves the sample, but also eliminates the influence of the matrix on the test result, thus saving the process of matching the standard curve solution with the matrix. The established method for detecting the chemical components in the hafnium oxide-modified silicon powder can undertake the detection task, and the detection result is accurate and reliable. 2. The samples processed by the method of the present invention have good accuracy and precision, and the reagents used in this method are simple and cheap, and multiple elements to be measured can be measured simultaneously. DETAILED DESCRIPTION

[0013] The specific implementation modes of the present invention are further described in detail below in conjunction with the examples. The following examples are used to illustrate the present invention but cannot be used to limit the scope of the present invention. Example 1

[0014] In this embodiment, the chemical composition and content to be tested of a hafnium oxide modified silicon powder are: The component analysis method specifically includes the following steps: Step (1) Sample preparation: After the hafnium oxide modified silicon powder sample is fully mixed, the quartering method is repeatedly adopted until the sample mass is 10.0 g.

[0015] Step (2) Dissolution of sample: Accurately weigh 0.1000g of the sample into a 250mL polytetrafluoroethylene cup, add 8mL of sulfuric acid and 4mL of hydrofluoric acid in sequence, add 1mL of nitric acid dropwise, heat on a 150℃ electric furnace until the sample is completely dissolved, and continue heating until a slight smoke appears; cool to room temperature, dilute to a 100mL plastic volumetric flask, and shake well for testing.

[0016] Step (3) Select the analytical spectrum of the element to be tested through element interference test: Prepare Hf, Fe, Al, Ca standard solutions with a concentration of 1 mg / 100 mL, and perform scanning tests on the Hf282.02nm, Fe259.4nm, Al394.4nm, and Ca393.3nm analysis lines, respectively. The element interference is determined by the intensity of the analysis line. The results are shown in Table 1: Table 1 Element interference test element Wavelength nm Hf Fe Al Ca Hf 282.0 325 0.047 0.086 0.012 Fe 259.4 0.012 58.32 0.023 0.075 Al 394.4 0.024 0.056 253 0.048 Ca 393.3 0.038 0.015 0.024 88.6 It can be seen from Table 1 that there is no interference between the Hf282.02nm, Fe259.4nm, Al394.4nm, and Ca393.3nm analysis lines, and the above analysis lines are selected as the analysis spectral lines.

[0017] Step (4) Establishment of analysis curve: Add 8 mL of 1:1 diluted sulfuric acid solution to four 100 mL plastic volumetric flasks respectively, add the standard solution content shown in Table 2, dilute to scale with water, shake well, and use as the working curve series solution. Use solution No. 1 as the "zero" concentration solution in the working curve series solution: Table 2 Amount of standard solution added Serial number content Hf Fe Al Ca 1 0.00mL 0.00mL 0.00mL 0.00mL 2 6.00mL 0.02mL 0.02mL 0.01mL 3 8.00mL 0.05mL 0.04mL 0.03mL 4 10.00mL 0.10mL 0.06mL 0.05mL Step (5) Measurement and calculation: Use inductively coupled plasma emission spectrometer for accurate analysis, adjust the instrument according to the instrument working conditions until the instrument is stable, and measure the spectral line intensity of Hf, Fe, Al, and Ca elements, specifically: Using the relationship between spectral line intensity and element content, the computer performs linear fitting, specifically: According to the working curve points, the k of the element Hf to be measured is 0.024, b is 0, and its signal intensity is 350. The Hf content is calculated to be 8.40 by the formula M(%)=kI+b, and the HfO2 content is calculated to be 9.91 by the conversion coefficient of hafnium 1.18; According to the working curve points, the k of the element Fe to be measured is 0.004, b is 0, and its signal intensity is 20. The Fe content is calculated to be 0.08 by the formula M(%)=kI+b; According to the working curve points, the k of the element Al to be measured is 0.0043, b is -0.2, and its signal intensity is 56. The Al content is calculated to be 0.04 by the formula M(%)=kI+b; According to the working curve points, the k of the element Ca to be measured is 0.0018, b is -0.5, and its signal intensity is 300. The Ca content is calculated to be 0.04 using the formula M(%)=kI+b.

Claims

1. A method for analyzing the chemical composition of hafnium oxide-modified silicon powder, characterized in that: The analysis method is as follows: the hafnium oxide modified silicon powder sample is completely dissolved by controlling the amount of acid, the order of addition, the temperature and the time to obtain a clear sample solution, and the interference of the matrix silicon is eliminated by fuming, so that the sample solution meets the analysis requirements of the inductively coupled plasma emission spectrometer; according to the content range of the element to be measured in the sample, a standard solution without silicon primer is prepared, and the analysis spectrum of the element to be measured is selected through the element interference test; a working curve series of solutions is established, and the intensity of each element to be measured in the test solution is measured on the inductively coupled plasma emission spectrometer under the selected conditions, and the intensity is proportional to the content of the element to be measured. The working curve is obtained by linear fitting by a computer, and the mass fraction of each element is obtained from the working curve.

2. The method for chemical composition analysis of hafnium oxide modified silicon powder according to claim 1, characterized in that: The hafnium oxide modified silicon powder sample is placed in a 250mL polytetrafluoroethylene cup, and the acid addition sequence is "sulfuric acid, hydrofluoric acid and nitric acid". The sample is placed on an electric furnace and heated to completely dissolve the hafnium oxide modified silicon powder sample. The sample is heated until a slight smoke is emitted, and the interference of the matrix silicon is eliminated by the sulfuric acid fume. After cooling, it is diluted to a 100mL plastic volumetric flask at room temperature and shaken for testing.

3. The method for chemical composition analysis of hafnium oxide modified silicon powder according to claim 2, characterized in that: Weigh 0.1000 g of a hafnium oxide-modified silicon powder sample, add 8 mL of sulfuric acid, 4 mL of hydrofluoric acid, and 1 mL of nitric acid.

4. The method for chemical composition analysis of hafnium oxide modified silicon powder according to claim 2, characterized in that: The temperature of the electric furnace is 150°C.

5. The method for chemical composition analysis of hafnium oxide modified silicon powder according to claim 1, characterized in that: Add 8 mL of 1:1 diluted sulfuric acid solution to multiple 100 mL plastic volumetric flasks respectively, add different amounts of Hf, Fe, Al, Ca, Cu, Cr, P, and B standard solutions according to the content range of the elements to be measured in the hafnium oxide modified silicon powder sample, dilute to the scale with water, shake well, and use them as the working curve series solutions. The solution without the element to be measured is used as the "zero" concentration solution in the working curve series solutions.

6. The method for chemical composition analysis of hafnium oxide modified silicon powder according to claim 5, characterized in that: In addition to the "zero" concentration solution, at least 3 solutions should be set in the working curve series.

7. The method for chemical composition analysis of hafnium oxide modified silicon powder according to claim 1, characterized in that: The set working curve points require that the gradient covers the content range of the component to be measured.

8. The method for chemical composition analysis of hafnium oxide modified silicon powder according to claim 1, characterized in that: According to the relationship between the spectral line intensity of each solution and the element content, a linear fit was performed to calculate the accurate content of the element to be measured, wherein hafnium oxide was converted by the hafnium content with a conversion factor of 1.

18. The formula for calculating the content of the element to be measured (M) was: M(%) = kI + b, where: k—represents the slope of the calibration curve; b—intercept of the working curve; I—measured signal intensity of the element to be measured.