Method for measuring content of multiple elements in high nickel-chromium alloy

Abstract

The invention discloses a method for measuring the content of multiple elements in a high nickel-chromium alloy, which comprises the following steps: S1, taking high-purity nickel powder, and adding nitric acid for dissolving to obtain a nickel matrix stock solution; taking high-purity chromium powder, and adding hydrochloric acid for dissolving to obtain a chromium standard solution; preparing a working curve mixed solution of manganese, silicon and titanium; s2, a high nickel-chromium alloy sample is weighed, hydrochloric acid (1 + 1), nitric acid and sulfuric acid (1 + 1) are added for dissolution, and an alloy solution is obtained; s3, adding barium salt to the alloy solution obtained in the step S2 to precipitate sulfate ions, and performing dry filtration with filter paper to obtain a to-be-detected alloy solution; and S4, detecting the working curve mixed solution obtained in the step S1 and the to-be-detected alloy solution obtained in the step S3 by using an inductively coupled plasma emission spectrometer to obtain the contents of manganese, silicon and titanium in the to-be-detected alloy solution. The method can realize simultaneous determination of the contents of various elements including silicon, and has the advantages of high sensitivity, good stability and high measurement accuracy.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of material and metallurgical analysis technology, and particularly relates to a method for measuring the content of multiple elements in high nickel-chromium alloy. BACKGROUND

[0002] High nickel-chromium alloy has significant advantages. High nickel-chromium ratio endows excellent corrosion resistance and oxidation resistance, high strength and toughness at high temperature, and moderate thermal expansion coefficient, ensuring structural stability. It is widely used in aerospace, nuclear energy, chemical industry and other fields, especially in the manufacturing of components in extreme environments, and has great market potential.

[0003] Currently, the composition of nickel-chromium alloy is mainly detected by inductively coupled plasma atomic emission spectrometry, which has high sensitivity, wide linear range, multi-element analysis, high selectivity, rapid analysis and other advantages. The sample pretreatment of the relatively difficult-to-dissolve sample generally selects dilute aqua regia-hydrochloric acid and sulfuric acid-nitric acid mixed acid system. The former cannot be used to determine the silicon content after sample pretreatment, and the viscosity of sulfuric acid in the latter is large, which easily blocks the capillary tube and affects the atomization efficiency. Therefore, it is necessary to establish an element content measurement method suitable for high nickel-chromium alloy. In the sample pretreatment stage, the method needs to use an acidic reagent containing high-viscosity sulfuric acid for treatment, and the high-viscosity sulfuric acid will not adversely affect the sampling efficiency of the inductively coupled plasma spectrometer (ICP). SUMMARY

[0004] To solve the above technical problems, the present application provides a method for detecting the content of manganese, silicon and titanium in high nickel-chromium alloy. The acidic reagent containing high-viscosity sulfuric acid is used for treatment to ensure complete dissolution of the sample. Further, the barium salt is used to precipitate sulfate ions and the detection parameters are optimized to simultaneously determine the content of multiple elements including silicon. The method has the advantages of high sensitivity, good stability and accurate measurement.

[0005] According to an aspect of the present application, a method for measuring the content of multiple elements in high nickel-chromium alloy is provided, which comprises the following steps:

[0006] In step S1, high-purity nickel powder with a purity greater than or equal to 99.99wt% is dissolved with nitric acid to obtain a nickel matrix stock solution. High-purity chromium powder with a purity greater than or equal to 99.99wt% is dissolved with hydrochloric acid to obtain a chromium standard solution. A working curve mixed solution of manganese, silicon and titanium is prepared using the nickel matrix stock solution, the chromium standard solution and the respective standard solutions of manganese, silicon and titanium.

[0007] In step S2, a high nickel-chromium alloy sample is weighed and dissolved with hydrochloric acid (1+1), nitric acid and sulfuric acid (1+1) to obtain an alloy solution.

[0008] Step S3, adding barium salt to the alloy solution obtained in step S2 to precipitate sulfate ions, and performing dry filtration with filter paper to obtain the alloy solution to be measured;

[0009] Step S4, detecting the working curve mixed solution obtained in step S1 and the alloy solution to be measured obtained in step S3 by using an inductively coupled plasma emission spectrometer to obtain the contents of manganese, silicon and titanium in the alloy solution to be measured.

[0010] Further, the specific steps for preparing the working curve mixed solution of manganese, silicon and titanium in step S1 are as follows: 12 mL of nickel matrix stock solution, 4 mL of chromium standard solution, 10 mL of hydrochloric acid and 5 mL of nitric acid are taken by using a 10 mL pipette and are added into 5 100 mL glass volumetric flasks, and 0 mL, 2 mL, 5 mL, 9 mL and 15 mL of standard solutions of manganese, silicon and titanium are taken respectively and are added into the above 5 volumetric flasks to be mixed, so as to obtain the working curve mixed solution, which is equivalent to 0.10 g of sample containing 0.00%, 0.2%, 0.5%, 0.9% and 1.5% of manganese, silicon and titanium in terms of mass fraction; the concentrations of the standard solutions of manganese, silicon and titanium are all 100 ug / mL.

[0011] Further, the concentration of nickel in the nickel matrix stock solution in step S1 is 5 mg / mL.

[0012] The concentration of chromium in the chromium standard solution in step S1 is 5 mg / mL.

[0013] Further, the specific steps for preparing the alloy solution in step S2 are as follows: a high-nickel chromium alloy sample is weighed and is added into a volumetric flask, hydrochloric acid (1+1), nitric acid and sulfuric acid (1+1) are added, and the mixture is heated on an electric furnace at 180-280 ℃, and after complete dissolution, the mixture is taken out and is cooled, deionized water is added to constant volume, and the mixture is shaken to obtain the alloy solution.

[0014] Further, the volume ratio of the hydrochloric acid (1+1), the nitric acid and the sulfuric acid (1+1) is 10-20:3-5:2-6.

[0015] Further, the barium salt in step S3 is barium carbonate solid with a purity of greater than 99.9 wt%.

[0016] Further, the specific steps of step S3 are as follows: the barium salt is weighed and is added into the volumetric flask containing the alloy solution obtained in step S2, and the mixture is shaken or is placed at 60-100 ℃ to promote the precipitation of barium sulfate, and then the liquid in the volumetric flask with the precipitate is filtered with a slow filter paper to a filter paper which is dried in advance, the filter paper is washed with a small amount of deionized water for multiple times, the mixture is diluted to the scale, and the mixture is shaken to obtain the alloy solution to be measured.

[0017] Further, the specific step of step S3 is: weighing the barium salt, adding into the volumetric flask containing the alloy solution of step S2, shaking or placing at 80 DEG C to promote the precipitation of barium sulfate, then filtering the liquid in the volumetric flask with precipitate into the pre-dried filter paper, washing the filter paper with deionized water for several times, diluting to the scale, and shaking to obtain the alloy solution to be detected.

[0018] Further, the working conditions of the inductively coupled plasma emission spectrometer in step S4 are as follows:

[0019] The flow rate of the atomizer gas is 0.5L / min-0.7L / min;

[0020] The plasma radio frequency power is 1300W-1400W;

[0021] The flow rate of the atomizer is 0.5L / min-0.65L / min;

[0022] The flow rate of the auxiliary gas is 0.4L / min-0.55L / min;

[0023] The pump speed of the peristaltic pump is 55rpm-65rpm;

[0024] The vertical observation height is 12.0mm;

[0025] The long-wave integration time is 10s-15s;

[0026] The short-wave integration time is 10s-15s.

[0027] Further, the detection of the working curve mixed solution obtained in step S1 in step S4 comprises: taking the mass fraction as the abscissa and the intensity as the ordinate to draw the working curve, and the linear correlation coefficients of the curves are all greater than 0.999.

[0028] Further, the specific steps of testing the content of manganese, silicon and titanium in the alloy solution to be detected in step S4 are as follows: introducing the alloy solution to be detected into the emission spectrometer after atomization through the sampling system, sequentially using the low standard solution and the high standard solution of manganese, silicon and titanium to standardize the instrument, when the working curve r is greater than or equal to 0.999, determining the alloy solution to be detected, comparing the determination result with the certified value of the standard sample to determine the optimal analysis spectral line of the element, and obtaining the content of manganese, silicon and titanium in the alloy solution to be detected.

[0029] Compared with the prior art, the present application has the following beneficial effects:

[0030] (1) The technical scheme disclosed by the present application dissolves a high-nickel chromium alloy sample with an acid reagent containing high-viscosity sulfuric acid, precipitates sulfate ions with a barium salt, eliminates the interference of high-viscosity sulfuric acid on the sampling efficiency of an inductively coupled plasma spectrometer, and preferably uses barium carbonate as a specific precipitant for sulfate ions. In the sample pretreatment process, carbonate ions can be effectively removed through a specific chemical environment (such as an acidic and heated condition), thereby significantly reducing interference factors in the detection process. Meanwhile, the technical scheme disclosed by the present application solves the problem that the traditional dilute aqua regia-perchloric acid dissolution method cannot test the silicon content in the sample, and provides a more accurate solution for the composition analysis of nickel-chromium alloys.

[0031] (2) The technical scheme disclosed by the present application uses inductively coupled plasma atomic emission spectrometry to detect the contents of manganese, silicon, and titanium in high-nickel chromium alloys, which can simultaneously determine multiple elements by dissolving a sample once. Meanwhile, high-purity nickel powder and chromium powder are dissolved and matched to form a working curve, thereby improving the detection accuracy. In addition, the detection results have high accuracy by virtue of the determination of the contents of national standard samples. Furthermore, the precision of the detection results is good by detecting a plurality of representative nickel-chromium alloys and further verifying the detection results. The method adopted by the present application has the characteristics of fast measurement speed and convenient operation, and can effectively save a large amount of human and material resources. DETAILED DESCRIPTION

[0032] The present application will be further described below in conjunction with specific embodiments, but the present application is not limited in any way by the embodiments.

[0033] The reagents used in the embodiments of the present application are as follows:

[0034] (1.1), hydrochloric acid, ρ 1.19 g / mL; super-purity;

[0035] (1.2), nitric acid, ρ 1.42 g / mL; super-purity;

[0036] (1.3), hydrochloric acid, 1+1 (volume ratio of hydrochloric acid to water 1:1);

[0037] (1.4), sulfuric acid, 1+1 (volume ratio of sulfuric acid to water 1:1);

[0038] (1.5), nickel matrix stock solution, 1 g of high-purity nickel powder described in S1 is dissolved in 40 mL of nitric acid (1.2), cooled, and diluted to 200 mL with deionized water, and mixed well. 1 mL of this solution contains 5 mg of nickel;

[0039] (1.6), chromium standard solution: 1 g of high-purity chromium powder described in S1 is dissolved in 40 mL of hydrochloric acid (1.1), cooled, and diluted to 200 mL with deionized water, and mixed well. 1 mL of this solution contains 5 mg of chromium;

[0040] (1.7) Manganese standard solution, 100 ug / mL;

[0041] (1.8) Silicon standard solution, 100 ug / mL;

[0042] (1.9) Titanium standard solution, 100 ug / mL.

[0043] The present application provides a method for measuring the content of multiple elements in high nickel-chromium alloy in the specific embodiment part, and the method comprises the following steps:

[0044] S1. Taking high-purity nickel powder with a purity greater than or equal to 99.99wt%, dissolving with nitric acid (1.2) to obtain a nickel matrix stock solution; taking high-purity chromium powder with a purity greater than or equal to 99.99wt%, dissolving with hydrochloric acid (1.1) to obtain a chromium standard solution; using the nickel matrix stock solution, the chromium standard solution, and the respective standard solutions of manganese, silicon, and titanium to prepare a working curve mixed solution of manganese, silicon, and titanium;

[0045] S2. Weighing a high nickel-chromium alloy sample, adding hydrochloric acid (1.3), nitric acid (1.2), and sulfuric acid (1.4) to dissolve, to obtain an alloy solution;

[0046] S3. Adding barium salt to the alloy solution obtained in step S2 to precipitate sulfate ions, and performing dry filtration with filter paper to obtain a to-be-tested alloy solution;

[0047] S4. Using an inductively coupled plasma emission spectrometer to detect the working curve mixed solution obtained in step S1, and using an inductively coupled plasma emission spectrometer to determine the to-be-tested alloy solution obtained in step S3, to obtain the content of manganese, silicon, and titanium in the to-be-tested alloy solution.

[0048] Based on the above technical solution, the concentration of nickel in the nickel matrix stock solution in step S1 is 5mg / mL, that is, 1g of high-purity nickel powder in step S1 is dissolved in 40mL of nitric acid (1.2), cooled, diluted with deionized water to 200mL, and mixed uniformly to obtain the nickel matrix stock solution.

[0049] Based on the above technical solution, the concentration of chromium in the chromium standard solution in step S1 is 5mg / mL, that is, 1g of high-purity chromium powder in step S1 is dissolved in 40mL of hydrochloric acid (1.1), cooled, diluted with deionized water to 200mL, and mixed uniformly to obtain the chromium standard solution.

[0050] Based on the above technical solution, the concentration of the respective standard solutions of manganese, silicon, and titanium in step S1 is 100ug / mL.

[0051] Based on the above technical scheme, the specific steps of preparing the mixed solution of manganese, silicon and titanium in step S1 are as follows: 12 mL of nickel matrix stock solution (1.5), 4 mL of chromium standard solution (1.6), 10 mL of hydrochloric acid (1.1) and 5 mL of nitric acid (1.2) are respectively mixed with the standard solutions of manganese, silicon and titanium to obtain the working curve mixed solution; the standard solutions of manganese, silicon and titanium are added in gradient within 0 mL-15.00 mL; the concentrations of the standard solutions of manganese, silicon and titanium are all 100 ug / mL.

[0052] Based on the above technical scheme, the specific steps of preparing the sample solution to be tested in step S2 are as follows: 0.10-0.5 g of high nickel-chromium alloy sample is weighed and placed in a 100 mL two-way volumetric flask, 10-20 mL of hydrochloric acid (1.3), 3-5 mL of nitric acid (1.2) and 2-6 mL of sulfuric acid (1.4) are respectively added, and the flask is heated on an electric furnace at 180-280°C. After complete dissolution, the flask is taken out and cooled, deionized water is added to constant volume, shaken well, and the alloy solution is obtained.

[0053] Based on the above technical scheme, the barium salt in step S3 is a barium carbonate solid with a purity greater than 99.9 wt%.

[0054] Based on the above technical scheme, the specific steps of step S3 are as follows: 3-17 g of barium salt is weighed and added to the sample solution to be tested in step S2. The precipitation of barium sulfate can be promoted by shaking or placing on an electric heating plate at 80-100°C. Then the liquid with precipitate is filtered onto a pre-dried 100 mL volumetric flask using slow filter paper. The filter paper is washed with a small amount of deionized water several times, diluted to the mark, shaken well, and the alloy solution to be tested is obtained.

[0055] Based on the above technical scheme, the working conditions of the inductively coupled plasma emission spectrometer in step S4 are as follows: the gas flow rate of the atomizer is 0.5 L / min-0.7 L / min; the plasma radio frequency power is 1300 W-1400 W; the atomizer flow rate is 0.5 L / min-0.65 L / min; the auxiliary gas flow rate is 0.4 L / min-0.55 L / min; the peristaltic pump speed is 55 rpm-65 rpm; the vertical observation height is 12.0 mm; the long wave integration time is 10 s-15 s; and the short wave integration time is 10 s-15 s.

[0056] Based on the above technical scheme, the specific steps of testing the content of manganese, silicon and titanium in the alloy solution to be tested in step S4 are as follows: the sample solution to be tested is atomized by the sample introduction system and introduced into the emission spectrometer. Low and high standard solutions of manganese, silicon and titanium are used in turn to standardize the instrument. When the working curve r is greater than or equal to 0.999, the determination of the alloy solution to be tested is carried out. The optimal analysis spectral line of the elements is determined by comparing the test results with the certified values of the standard samples, and the content of manganese, silicon and titanium in the alloy solution to be tested is obtained.

[0057] Example 1

[0058] (1) The working conditions of the inductively coupled plasma atomic emission spectrometer are as follows: the flow rate of the atomizer gas is 0.60 L / min; the plasma radio frequency power is 1350 W; the flow rate of the atomizer is 0.60 L / min; the flow rate of the auxiliary gas is 0.50 L / min; the peristaltic pump speed is 60 rpm; the vertical observation height is 12.0 mm; the long wave integration time is 10 s; and the short wave integration time is 10 s.

[0059] (2) Sample dissolution: two 0.1 g high-nickel chromium alloy samples are weighed to an accuracy of 0.0001 g; the samples are placed in 100 mL capacity bottles, 20 mL of hydrochloric acid (1.3), 5 mL of nitric acid (1.2), and 2 mL of sulfuric acid (1.4) are added, and the samples are slightly heated on a 200°C electric hot plate until they are dissolved; the capacity bottles are removed from the electric hot plate and slightly cooled, 4 g and 6 g of barium carbonate solid with a purity of ≥99.9 wt% are added respectively, and the samples are placed on an 80°C electric hot plate to promote the precipitation of barium sulfate, dry filtration is performed on slow filter paper, the filter paper is washed with a small amount of deionized water for several times, diluted to the calibration mark, shaken well, and the sample solution to be tested is obtained;

[0060] (3) Preparation of working curve mixed solution: 12 mL of nickel matrix stock solution (1.5), 4 mL of chromium standard solution (1.6), 10 mL of hydrochloric acid (1.1), and 5 mL of nitric acid (1.2) are taken with a 20 mL pipette and added to five 100 mL glass capacity bottles, and 0 mL, 2 mL, 5 mL, 9 mL, and 15 mL of manganese, silicon, and titanium standard solutions are taken and added to the above five capacity bottles to obtain working curve mixed solutions, which are equivalent to 0.00%, 0.2%, 0.5%, 0.9%, and 1.5% of the mass fraction of manganese, silicon, and titanium elements in 0.10 g of the sample; the concentrations of the manganese, silicon, and titanium standard solutions are all 100 ug / mL.

[0061] (4) The working curve mixed solution is measured by the plasma atomic emission spectrometer, the mass fraction is taken as the abscissa, and the intensity is taken as the ordinate to draw the working curve, and the linear correlation coefficients of the curve are all greater than 0.999. On the basis of the working curve, the sample solution to be tested described in step (2) is measured by the plasma atomic emission spectrometer, λ Mn = 257.610 nm, λ Si = 251.611 nm, and λ Ti= 337.280 nm, the addition of 2 mL of sulfuric acid (1 + 1) has a positive effect on the dissolution process of the sample. However, the detection values of each element are still lower than the certified values of the standard sample, which can be inferred that the current amount of sulfuric acid added has not reached the degree of sufficient dissolution or meets the detection requirements. Compared with the element detection results of Comparative Example 1, the detection values of each element in Example 1 are improved, indicating that when the molar ratio of barium ions to sulfate ions is set to 1.5:1, the relative standard deviation (RSD) value shows a smaller trend. This result shows that under the condition of the presence of excess barium ion concentration for precipitating sulfate, the obtained detection data exhibits good precision.

[0062] Table 1 is the test results of the content of manganese, silicon and titanium in the sample solution to be tested in Example 1

[0063]

[0064]

[0065] Comparative Example 1

[0066] The difference between Example 1 and Comparative Example 1 is that the barium carbonate solid is not added after the sample solution is taken off the hot plate in step (2). The specific steps of the sample solution dissolution in step (2) are as follows: 0.1 g of high-nickel chromium alloy sample is weighed to 0.0001 g; the sample is placed in a 100 mL volumetric flask, 20 mL of hydrochloric acid (1.3) and 5 mL of nitric acid (1.2) are added, and the sample is heated to dissolution on a 200°C hot plate; the volumetric flask is taken off the hot plate and slightly cooled, then diluted to the mark with deionized water, shaken well, and the sample solution to be tested is obtained. The rest of the steps are consistent with Example 1. The specific detection results are shown in Table 2, and the measured values of each element are lower than the certified values. Combined with the observation of sample pretreatment, after continuous dissolution at 200°C for nearly 40 minutes, a small amount of unreacted residue and micro-bubbles are still observed, indicating that the pure hydrochloric acid-nitric acid mixed acid system cannot completely dissolve the sample. At the same time, silicon particles are precipitated on the wall of the volumetric flask, which is consistent with the result that the measured value of silicon is significantly lower than the certified value.

[0067] Table 2 is the test results of the content of manganese, silicon and titanium in the sample solution of Comparative Example 1

[0068]

[0069] Example 2

[0070] The difference between Example 1 is that the amount of hydrochloric acid, nitric acid, sulfuric acid, barium carbonate added in the sample dissolution of step (2) is different, i.e. the specific steps of the sample dissolution of step (2) are: two 0.1 g high nickel chromium alloy samples are weighed to 0.0001 g; the samples are placed in a 100 mL volumetric flask, 15 mL of hydrochloric acid (1.3), 4 mL of nitric acid (1.2) and 4 mL of sulfuric acid (1.4) are added, and the sample is dissolved on a 200°C hot plate; the volumetric flask is removed from the hot plate and cooled slightly, 11 g and 15 g of barium carbonate solid with a purity of ≥99.9wt% are added respectively, and the sample is placed on a 80°C hot plate to promote the precipitation of barium sulfate, and is slowly filtered on filter paper, and the filter paper is washed with deionized water for several times, diluted to the scale, shaken well, and the test sample solution is obtained, and the remaining steps are the same as those of Example 1. The specific test results are shown in Table 3. The element test results are highly consistent with the certified values of the standard sample, indicating that the addition of 4 mL of sulfuric acid (1+1) can meet the experimental requirements of fully dissolving the sample. At the same time, when the molar ratio of barium ions to sulfate ions is set to 1.5:1 and 2:1, the relative standard deviation (RSD) value is basically unchanged. This result shows that when the molar ratio of barium ions to sulfate ions is set to 1.5:1, the accuracy and reliability requirements of the detection work can be fully met.

[0071] Table 3 is the test results of the content of manganese, silicon and titanium in the sample solution of Example 2

[0072]

[0073] Example 3

[0074] The difference between Example 1 is that the sample dissolution in step (2) is added with barium carbonate solid with purity ≥ 99.9wt%, barium chloride dihydrate solid with purity ≥ 99.9wt%, that is, the specific steps of the sample dissolution in step (2) are: two 0.1g high nickel chromium alloy samples are weighed to 0.0001g; the samples are placed in a 100mL volumetric flask, 15mL hydrochloric acid (1.3), 4mL nitric acid (1.2) and 4mL sulfuric acid (1.4) are added, and the sample is slightly heated on a 200℃ hot plate until it dissolves; the volumetric flask is taken off the hot plate and slightly cooled, 11g of barium carbonate solid with purity ≥ 99.9wt% and 14g of barium chloride dihydrate solid with purity ≥ 99.9wt% are added respectively, and the sample is placed on a 80℃ hot plate to promote the precipitation of barium sulfate, and is slowly filtered on filter paper, washed with deionized water for several times, diluted to the mark, shaken well, and the sample solution is obtained, and the remaining steps are the same as Example 1. The specific test results are shown in Table 4. The measurement results show that under different conditions of barium salt used for precipitating sulfate, compared with using barium chloride dihydrate as the precipitant, when barium carbonate is used as the precipitant for sulfate, the element test results show higher accuracy and better precision. At the same time, if barium salt containing chloride ions is used as the precipitant, salt accumulation will inevitably occur in the long-term experimental detection environment, which will cause problems such as atomizer blockage, and pose a potential threat to the normal operation of the detection equipment and the accuracy of the test results. However, using barium salt containing carbonate as the precipitant can effectively avoid the above problems. The carbonate is removed in the acidic and heated environment during the sample pretreatment process, further reducing the detection interference factors.

[0075] Table 4 is the test results of the content of manganese, silicon and titanium in the sample solution of Example 3

[0076]

[0077]

[0078] Example 4

[0079] The difference from Example 1 is that the amounts of hydrochloric acid, nitric acid, sulfuric acid and barium carbonate added in the sample dissolution in step (2) are different, that is, the specific steps of the sample dissolution in step (2) are as follows: weigh 0.1g of high nickel-chromium alloy sample, accurate to 0.0001g; place the sample in a 100mL volumetric flask, add 10mL of hydrochloric acid (1.3), 3mL of nitric acid (1.2) and 6mL of sulfuric acid (1.4), and heat slightly on a 200℃ hot plate until the sample is dissolved; remove the volumetric flask from the hot plate and cool it slightly, add 17 g barium carbonate solid with a purity of ≥99.9wt%, placed on an 80℃ electric hot plate to heat and promote the formation of barium sulfate precipitation, dry filter with slow filter paper, and rinse the filter paper with deionized water in small amounts and multiple times, dilute to the scale, shake well, and obtain the test sample solution. The remaining steps are consistent with Example 1. The specific test results are shown in Table 5. The measurement results show that when 6mL of sulfuric acid (1+1) is added, except for silicon, the measured values ​​of other elements are highly close to the standard sample identification value, indicating that this acidic environment can meet the experimental requirements of fully dissolving the sample. However, the measured value of silicon in the sample is significantly lower than the standard sample identification value. This is because barium carbonate needs to be heated to increase the H in the sample solution. + 、SO4 2- Reaction, when SO4 in solution 2- The reaction time required for completion is correspondingly longer due to the presence of a high concentration of sulfate ions. During this process, the soluble silicic acid in the sample solution, exposed to a strong acid environment for a long time, may undergo further hydrolysis, leading to the formation of silicic acid coagulation and precipitation. This side reaction seriously interferes with the accurate determination of silicon content. Furthermore, when the sample solution contains excessive sulfate ions, the amount of barium carbonate precipitant must be increased to ensure the complete precipitation reaction, increasing the cost of analysis and testing.

[0080] Table 5 shows the test results of the contents of manganese, silicon and titanium in the sample solution described in Example 4.

[0081]

[0082] Example 5

[0083] The difference between Example 1 is that the amount of hydrochloric acid, nitric acid, sulfuric acid, barium carbonate added in the sample dissolution of step (2) is different, that is, the specific steps of the sample dissolution of step (2) are: two other different 0.1g high nickel chromium alloy samples (alloy 1, alloy 2) are weighed to 0.0001g; the sample is placed in a 100mL volumetric flask, 15mL hydrochloric acid (1.3), 4mL nitric acid (1.2) and 4mL sulfuric acid (1.4) are added, and the sample is dissolved on a 200℃ electric heating plate; the volumetric flask is taken off the electric heating plate and cooled slightly, 15g of barium carbonate solid with a purity of ≥99.9wt% is added, and the sample is placed on an 80℃ electric heating plate to promote the precipitation of barium sulfate, slow-speed filter paper is used for dry filtration, and the filter paper is washed with a small amount of deionized water several times, diluted to the scale, shaken uniformly, and the test sample solution is obtained, and the remaining steps are the same as Example 1. The specific test results are shown in Table 6, and the results show that under the optimized and determined better detection conditions, the detection method is applied to the detection and analysis of other high nickel chromium alloy standard samples, and the measurement results of each element show a high degree of consistency with the standard certified value. This result shows that the proposed detection method not only has wide applicability and can be applied to the analysis of different types of high nickel chromium alloy samples, but also has high sensitivity and stability.

[0084] Table 6 is the test results of the content of manganese, silicon and titanium in the sample solution of Example 5

[0085]

[0086] The above is only a few embodiments of the present application, and does not limit the present application in any form. Although the present application is disclosed as above, it is not intended to limit the present application. Any skilled person in the art can make some changes or modifications to the above disclosed technical content without departing from the scope of the technical solution of the present application, which are equivalent to equivalent embodiments and belong to the scope of the technical solution.

Claims

1. A method for measuring the content of multiple elements in high nickel-chromium alloy, characterized in that: The method comprises the following steps: Step S1, taking high-purity nickel powder with a purity greater than or equal to 99.99 wt%, adding nitric acid to dissolve it, and obtaining a nickel matrix stock solution; taking high-purity chromium powder with a purity greater than or equal to 99.99 wt%, adding hydrochloric acid to dissolve it, and obtaining a chromium standard solution; Prepare mixed solutions of working curves of manganese, silicon and titanium using nickel matrix stock solution, chromium standard solution and respective standard solutions of manganese, silicon and titanium; Step S2, weighing a high nickel-chromium alloy sample, adding hydrochloric acid (1+1), nitric acid and sulfuric acid (1+1) to dissolve the sample to obtain an alloy solution; Step S3, adding barium salt to the alloy solution obtained in step S2 to precipitate sulfate ions, and performing dry filtration with filter paper to obtain an alloy solution to be tested; Step S4, using an inductively coupled plasma emission spectrometer to detect the working curve mixed solution obtained in step S1 and the alloy solution to be tested obtained in step S3, to obtain the contents of manganese, silicon, and titanium in the alloy solution to be tested.

2. The method according to claim 1, characterized in that The specific steps of preparing the working curve mixed solution of manganese, silicon, and titanium in step S1 are as follows: using a 10mL pipette to pipette 12mL of nickel matrix stock solution, 4mL of chromium standard solution, 10mL of hydrochloric acid, and 5mL of nitric acid into 5 100mL glass volumetric flasks, and taking 0mL, 2mL, 5mL, 9mL, and 15mL of manganese, silicon, and titanium standard solutions into the above 5 volumetric flasks respectively to mix to obtain a working curve mixed solution, which is equivalent to containing manganese, silicon, and titanium elements with mass fractions of 0.00%, 0.2%, 0.5%, 0.9%, and 1.5% in 0.10g of sample; the concentrations of the manganese, silicon, and titanium standard solutions are all 100ug / mL.

3. The method according to claim 1, characterized in that The nickel concentration in the nickel matrix stock solution in step S1 is 5 mg / mL; The concentration of chromium in the chromium standard solution in step S1 is 5 mg / mL.

4. The method according to claim 1, wherein The specific steps of preparing the alloy solution in step S2 are: weighing a high nickel-chromium alloy sample into a volumetric flask, adding hydrochloric acid (1+1), nitric acid, and sulfuric acid (1+1), heating on an electric furnace at 180-280° C., removing and cooling after complete dissolution, adding deionized water to the volume, and shaking to obtain an alloy solution; Preferably, the volume ratio of hydrochloric acid (1+1), nitric acid, and sulfuric acid (1+1) is 10-20:3-5:2-6.

5. The method according to claim 1, wherein The barium salt in step S3 is barium carbonate solid with a purity greater than 99.9 wt%.

6. The method according to claim 1, characterized in that The specific steps of step S3 are: weighing the barium salt, adding it to the volumetric flask containing the alloy solution in step S2, shaking or placing it at 60-100°C to promote the formation of barium sulfate precipitation, then filtering the liquid in the volumetric flask with precipitate formation with slow filter paper until it is dried in advance, rinsing the filter paper with deionized water in small amounts multiple times, diluting to the scale, and shaking well to obtain the alloy solution to be tested.

7. The method according to claim 1, characterized in that The operating conditions of the inductively coupled plasma optical emission spectrometer in step S4 are as follows: The nebulizer gas flow rate is 0.5L / min to 0.7L / min; The plasma radio frequency power is 1300W to 1400W; The nebulizer flow rate is 0.5L / min to 0.65L / min; Auxiliary gas flow rate is 0.4L / min~0.55L / min; The peristaltic pump speed is 55 rpm to 65 rpm; The vertical observation height is 12.0 mm; The long-wave integration time is 10s to 15s; The shortwave integration time is 10s to 15s.

8. The method according to claim 1, characterized in that The step S4 of detecting the working curve mixed solution obtained in the step S1 includes: drawing a working curve with mass fraction as the abscissa and intensity as the ordinate, and the linear correlation coefficient of the curve is greater than 0.

999.

9. The method according to claim 1, characterized in that The specific steps of testing the content of manganese, silicon, and titanium in the alloy solution to be tested in step S4 are as follows: the alloy solution to be tested is atomized by the sampling system and then introduced into the emission spectrometer, and the instrument is standardized with low-standard solutions and high-standard solutions of manganese, silicon, and titanium in sequence. When the working curve r ≥ 0.999, the alloy solution to be tested is measured, and the optimal analysis spectrum of the element is determined by comparing the measurement results with the identification values ​​of the standard sample to obtain the content of manganese, silicon, and titanium in the alloy solution to be tested.

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