Method for measuring germanium and cobalt content in silver-copper alloy
By using dilute nitric acid digestion and lanthanum internal standard control, combined with inductively coupled plasma atomic emission spectrometry (ICP-AES), the instability in the determination of germanium and cobalt content in silver-copper alloys was resolved, and highly accurate detection of germanium and cobalt content was achieved.
Patent Information
- Application Number
- CN202511926185.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-19
- Publication Date
- 2026-01-30
AI Technical Summary
Existing methods for determining germanium in silver-copper alloys suffer from several drawbacks: GeCl4 is easily volatile, leading to low results; and the lack of internal standard control results in unstable germanium-cobalt content determination.
The silver-copper alloy was digested with dilute nitric acid, and AgBr precipitate was generated and separated. Lanthanum was used as an internal standard, and the germanium and cobalt content was determined by inductively coupled plasma atomic emission spectrometry. A standard working curve was established, and the germanium and cobalt content in the alloy was calculated.
It significantly improves the accuracy and stability of germanium and cobalt determination results, solves the problem of low determination caused by GeCl4 volatilization, and enhances the reliability and precision of detection.
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Abstract
Description
Technical Field
[0001] This invention relates to a method for determining the germanium and cobalt content in silver-copper alloys, belonging to the field of precious metal alloy material testing technology. Background Technology
[0002] Silver-based solders are the oldest and most widely used type of solder. Due to their suitable melting point, good conductivity, high strength and ductility, good machinability, and good corrosion resistance in various media, they are extensively used in the production of vacuum electronic devices. Silver-based solders can be classified by composition as Ag-Cu, Ag-Cu-Ni, Ag-Cu-Pd, etc. Ag-Cu eutectic (Ag-Cu28) solder is very common, accounting for over 80% of the total solder used in vacuum electronic device manufacturing. Research has found that adding certain amounts of germanium and cobalt to Ag-Cu alloys can strengthen the alloy structure, improve machinability, and enhance corrosion resistance and conductivity (Ag-Cu-Ge-Co). Rapid and accurate analysis of the germanium and cobalt content in silver-copper alloys is a powerful guarantee for fair and equitable product transactions and provides strong support for ensuring product quality. The current determination method mainly involves dissolving the sample in nitric acid, adding hydrochloric acid to generate AgCl precipitate in the silver matrix solution, filtering the AgCl precipitate, and then using inductively coupled plasma atomic emission spectrometry (ICP-AES) to determine the germanium and cobalt content in the filtrate. This method is prone to causing the generated GeCl4 to volatilize (GeCl4 is highly volatile at ≥86℃), resulting in a lower germanium determination result. Furthermore, no internal standard control is used during the determination process, leading to poor stability of results for high-content germanium and cobalt. Summary of the Invention
[0003] The determination of germanium and cobalt content in silver-copper alloys faces several challenges, including the easy volatilization of GeCl4 (GeCl4's volatility is ≥86℃), leading to low germanium measurement results, lack of internal standard control during measurement, and poor stability of results for high-content germanium and cobalt alloys. This invention proposes a method for determining the germanium and cobalt content in silver-copper alloys. The method involves digesting the silver-copper alloy with dilute nitric acid, adding hydrobromic acid to precipitate AgBr in the silver matrix, boiling, and filtering the AgBr precipitate to obtain the germanium and cobalt test solution. A germanium and cobalt standard working solution is prepared using lanthanum as an internal standard. The output spectral intensity of the germanium and cobalt standard working solution is measured using inductively coupled plasma atomic emission spectrometry (ICP-AES) to establish standard working curves for germanium and cobalt concentrations. Based on these standard working curves, the germanium and cobalt ion concentrations in the test solution are measured using ICP-AES, and the germanium and cobalt content in the silver-copper alloy is then calculated. This invention significantly improves the accuracy of germanium and cobalt determination results.
[0004] A method for determining the germanium and cobalt content in a silver-copper alloy, the specific steps of which are as follows: (1) Accurately weighed La2O3 was added to commercially available nitric acid solution and heated to dissolve. After cooling, the solution was diluted with deionized water to obtain lanthanum internal standard solution. (2) Add the silver-copper alloy to a dilute nitric acid solution and digest it at a temperature of 130~150℃. Cool it to room temperature to obtain the digestion solution. (3) Add hydrobromic acid to the digestion solution to generate AgBr precipitate of silver ions, and boil at 110~130℃ until the solution is clear. Separate the solid and liquid to obtain the filtrate, add lanthanum internal standard solution to the filtrate, and dilute with deionized water to obtain germanium and cobalt test solution. (4) Add commercially available nitric acid and hydrobromic acid to a volumetric flask, accurately transfer germanium-cobalt standard stock solution, and prepare germanium-cobalt standard working solutions with concentrations of 0.00, 1.00 µg / mL, 5.00 µg / mL, 10.00 µg / mL, 25.00 µg / mL, and 50.00 µg / mL, respectively. Add lanthanum internal standard solution to each germanium-cobalt standard working solution. (5) The output spectral intensities of several germanium and cobalt standard working solutions were measured using an inductively coupled plasma atomic emission spectrometer, and standard working curves for germanium and cobalt concentrations were established respectively. (6) The output spectral intensity of the germanium-cobalt test solution was measured using an inductively coupled plasma atomic emission spectrometer. The germanium ion concentration and cobalt ion concentration in the germanium-cobalt test solution were calculated based on the standard working curves of germanium and cobalt concentrations, respectively. Then the germanium content and cobalt content in the silver-copper alloy were calculated.
[0005] Preferably, in step (1), the concentration of commercially available nitric acid is 14.4~15.2 mol / L, and the concentration of lanthanum in the lanthanum internal standard solution is 2 mg / mL.
[0006] Preferably, in step (2), the concentration of the dilute nitric acid solution is 4.00~7.94mol / L, and the mass ratio of dilute nitric acid to silver-copper alloy is 20~60:1.
[0007] Preferably, in step (3), the germanium content in the germanium-cobalt test solution is 0.001~0.05 mg / mL, the cobalt content is 0.001~0.05 mg / mL, and the amount of lanthanum internal standard solution added to 100 mL of germanium-cobalt test solution is 1 mL.
[0008] Preferably, in step (4), the concentration of commercially available nitric acid is 14.4~15.2 mol / L, the concentration of hydrobromic acid is 0.12~0.37 mol / L, the amount of commercially available nitric acid added to 100 mL of germanium-cobalt standard working solution is 3~7 mL, the amount of hydrobromic acid added is 1~3 mL, and the amount of lanthanum internal standard solution added is 1 mL.
[0009] The formula for calculating the germanium or cobalt content in the silver-copper alloy in step (6) is as follows: ; Where: W% - mass fraction of germanium or cobalt content, %; C - concentration of germanium or cobalt after subtracting blank from the measured concentration, µg / mL; V - volume of germanium-cobalt test solution, mL; m - weight of silver-copper alloy, g.
[0010] The beneficial effects of this invention are: (1) The present invention uses dilute nitric acid to digest the sample, which prevents passivation of the alloy surface and enhances the decomposition ability of the alloy sample. (2) The present invention uses hydrobromic acid to separate the silver matrix, which can solve the problem of the volatility of GeCl4 (≥86℃) and the low germanium determination result in the existing method, and further improve the accuracy of detection; (3) The present invention uses lanthanum as an internal standard to control the determination process, which solves the instability of the determination results of high-content germanium and cobalt and significantly improves the accuracy of the determination results of germanium and cobalt; (4) The present invention separates the AgBr precipitate and then uses inductively coupled plasma atomic emission spectrometry to determine the germanium and cobalt content in the filtrate. It has the characteristics of accurate results, high efficiency, strong applicability and easy mastery. Attached Figure Description
[0011] Figure 1 For the germanium concentration standard working curve; Figure 2 This is a standard working curve for cobalt concentration. Detailed Implementation
[0012] The present invention will be further described in detail below with reference to specific embodiments, but the scope of protection of the present invention is not limited to the content described.
[0013] Example 1: Eleven measurements were performed on silver-copper alloy sample #1 with a standard value of germanium content of 0.50% (mass fraction) and a standard value of cobalt content of 0.30% (mass fraction), and the average value and relative standard deviation were calculated. A method for determining the germanium and cobalt content in a silver-copper alloy, the specific steps of which are as follows: (1) Accurately weighed La2O3 (accurate to 0.0001 g) was added to commercially available nitric acid solution and heated to dissolve. After cooling, the solution was diluted to 500 mL with deionized water to obtain lanthanum internal standard solution. The concentration of lanthanum in the lanthanum internal standard solution was 2 mg / mL. (2) Add the silver-copper alloy (accurate to 0.0001g) to a dilute nitric acid solution, digest it at 130℃, and cool it to room temperature to obtain a digestion solution; the concentration of the dilute nitric acid solution is 4.00mol / L, and the mass ratio of dilute nitric acid to silver-copper alloy is 30:1; (3) Add a small amount of hydrobromic acid to the digestion solution to generate AgBr precipitate of silver ions, and boil at 110°C until the solution is clear. Separate the solid and liquid to obtain the filtrate, add lanthanum internal standard solution to the filtrate, and dilute with deionized water to obtain germanium-cobalt test solution; the amount of lanthanum internal standard solution added to 100mL of germanium-cobalt test solution is 1mL. (4) Add commercially available nitric acid and hydrobromic acid to a volumetric flask, accurately transfer germanium-cobalt standard stock solution, and prepare germanium-cobalt standard working solutions with concentrations of 0.00, 1.00 µg / mL, 5.00 µg / mL, 10.00 µg / mL, 25.00 µg / mL, and 50.00 µg / mL, respectively. Add lanthanum internal standard solution to each germanium-cobalt standard working solution. The concentration of hydrobromic acid is 0.37 mol / L. The amount of commercially available nitric acid added to 100 mL of germanium-cobalt standard working solution is 3 mL, the amount of hydrobromic acid added is 3 mL, and the amount of lanthanum internal standard solution added is 1 mL. (5) The output spectral intensities of several germanium and cobalt standard working solutions were measured using an inductively coupled plasma atomic emission spectrometer (wavelength: 303.906 nm for germanium and 236.380 nm for cobalt), and standard working curves for germanium concentration were established respectively (see Figure 1 ) and cobalt concentration standard working curve (see Figure 2 ); (6) The output spectral intensity of the germanium-cobalt test solution was measured by an inductively coupled plasma atomic emission spectrometer (wavelength: 303.906 nm for germanium and 236.380 nm for cobalt). The concentrations of germanium ions and cobalt ions in the germanium-cobalt test solution were calculated based on the standard working curves of germanium and cobalt concentrations, respectively. Then the germanium content and cobalt content in the silver-copper alloy were calculated. The formula for calculating the germanium or cobalt content in silver-copper alloys is as follows: ; Where: W% - mass fraction of germanium or cobalt content, %; C - concentration of germanium or cobalt after subtracting blank from the measured concentration, µg / mL; V - volume of germanium-cobalt test solution, mL; m - weight of silver-copper alloy, g; The results of 11 measurements (germanium and cobalt content in the silver-copper alloy) for sample #1 of this embodiment, along with the average value and relative standard deviation, are shown in Table 1. Table 1. Determination results of germanium and cobalt content, average values, and relative standard deviations of silver-copper alloy sample #1. ; As shown in Table 1, the digestion effect of the silver-copper sample in this embodiment is good, germanium does not volatilize, the measurement results are stable, and the relative standard deviations are 1.17% for germanium and 1.08% for cobalt. The method in this embodiment greatly improves the accuracy of the determination of germanium and cobalt content in silver-copper alloys.
[0014] Example 2: Eleven measurements were performed on silver-copper alloy sample #2 with a standard value of 2.0% (mass fraction) for germanium content and 0.30% (mass fraction) for cobalt content, and the average value and relative standard deviation were calculated. A method for determining the germanium and cobalt content in a silver-copper alloy, the specific steps of which are as follows: (1) Accurately weighed La2O3 (accurate to 0.0001 g) was added to commercially available nitric acid solution and heated to dissolve. After cooling, the solution was diluted to 500 mL with deionized water to obtain lanthanum internal standard solution. The concentration of lanthanum in the lanthanum internal standard solution was 2 mg / mL. (2) Add the silver-copper alloy (accurate to 0.0001g) to a dilute nitric acid solution, digest it at 140℃, and cool it to room temperature to obtain a digestion solution; the concentration of the dilute nitric acid solution is 5.62mol / L, and the mass ratio of dilute nitric acid to silver-copper alloy is 25:1; (3) Add a small amount of hydrobromic acid to the digestion solution to generate AgBr precipitate of silver ions, and boil at 120°C until the solution is clear. Separate the solid and liquid to obtain the filtrate, add lanthanum internal standard solution to the filtrate, and dilute with deionized water to obtain germanium-cobalt test solution; the amount of lanthanum internal standard solution added to 100mL of germanium-cobalt test solution is 1mL. (4) Add commercially available nitric acid and hydrobromic acid to a volumetric flask, accurately transfer germanium-cobalt standard stock solution, and prepare germanium-cobalt standard working solutions with concentrations of 0.00, 1.00 µg / mL, 5.00 µg / mL, 10.00 µg / mL, 25.00 µg / mL, and 50.00 µg / mL, respectively. Add lanthanum internal standard solution to each germanium-cobalt standard working solution. The concentration of hydrobromic acid is 0.31 mol / L. The amount of commercially available nitric acid added to 100 mL of germanium-cobalt standard working solution is 4 mL, the amount of hydrobromic acid added is 2.5 mL, and the amount of lanthanum internal standard solution added is 1 mL. (5) The output spectral intensities of several germanium and cobalt standard working solutions were measured using an inductively coupled plasma atomic emission spectrometer (wavelength: 303.906 nm for germanium and 236.380 nm for cobalt), and standard working curves for germanium concentration were established respectively (see Figure 1 ) and cobalt concentration standard working curve (see Figure 2 ); (6) The output spectral intensity of the germanium-cobalt test solution was measured by an inductively coupled plasma atomic emission spectrometer (wavelength: 303.906 nm for germanium and 236.380 nm for cobalt). The concentrations of germanium ions and cobalt ions in the germanium-cobalt test solution were calculated based on the standard working curves of germanium and cobalt concentrations, respectively. Then the germanium content and cobalt content in the silver-copper alloy were calculated. The formula for calculating the germanium or cobalt content in silver-copper alloys is as follows: ; Where: W% - mass fraction of germanium or cobalt content, %; C - concentration of germanium or cobalt after subtracting blank from the measured concentration, µg / mL; V - volume of germanium-cobalt test solution, mL; m - weight of silver-copper alloy, g; The results of 11 measurements (germanium and cobalt content in the silver-copper alloy) for sample #2 in this embodiment, along with the average value and relative standard deviation, are shown in Table 2. Table 2. Determination results of germanium and cobalt content, average values, and relative standard deviations of silver-copper alloy sample #2. ; As shown in Table 2, the digestion effect of the silver-copper sample in this embodiment is good, germanium does not volatilize, the measurement results are stable, and the relative standard deviations are 0.85% for germanium and 1.75% for cobalt. This embodiment significantly improves the accuracy of the determination of germanium and cobalt content in silver-copper alloys.
[0015] Example 3: Eleven measurements were performed on silver-copper alloy sample #3 with a standard value of 5.0% (mass fraction) for germanium content and 1.0% (mass fraction) for cobalt content, and the average value and relative standard deviation were calculated. A method for determining the germanium and cobalt content in a silver-copper alloy, the specific steps of which are as follows: (1) Accurately weighed La2O3 (accurate to 0.0001 g) was added to commercially available nitric acid solution and heated to dissolve. After cooling, the solution was diluted to 500 mL with deionized water to obtain lanthanum internal standard solution. The concentration of lanthanum in the lanthanum internal standard solution was 2 mg / mL. (2) Add the silver-copper alloy (accurate to 0.0001g) to a dilute nitric acid solution, digest it at 145℃, and cool it to room temperature to obtain a digestion solution; the concentration of the dilute nitric acid solution is 6.50mol / L, and the mass ratio of dilute nitric acid to silver-copper alloy is 50:1; (3) Add a small amount of hydrobromic acid to the digestion solution to generate AgBr precipitate of silver ions, and boil at 125°C until the solution is clear. Separate the solid and liquid to obtain the filtrate, add lanthanum internal standard solution to the filtrate, and dilute with deionized water to obtain germanium-cobalt test solution; the amount of lanthanum internal standard solution added to 100mL of germanium-cobalt test solution is 1mL. (4) Add commercially available nitric acid and hydrobromic acid to a volumetric flask, accurately transfer germanium-cobalt standard stock solution, and prepare germanium-cobalt standard working solutions with concentrations of 0.00, 1.00 µg / mL, 5.00 µg / mL, 10.00 µg / mL, 25.00 µg / mL, and 50.00 µg / mL, respectively. Add lanthanum internal standard solution to each germanium-cobalt standard working solution. The concentration of hydrobromic acid is 0.25 mol / L. The amount of commercially available nitric acid added to 100 mL of germanium-cobalt standard working solution is 5 mL, the amount of hydrobromic acid added is 2 mL, and the amount of lanthanum internal standard solution added is 1 mL. (5) The output spectral intensities of several germanium and cobalt standard working solutions were measured using an inductively coupled plasma atomic emission spectrometer (wavelength: 303.906 nm for germanium and 236.380 nm for cobalt), and standard working curves for germanium concentration were established respectively (see Figure 1 ) and cobalt concentration standard working curve (see Figure 2 ); (6) The output spectral intensity of the germanium-cobalt test solution was measured by an inductively coupled plasma atomic emission spectrometer (wavelength: 303.906 nm for germanium and 236.380 nm for cobalt). The concentrations of germanium ions and cobalt ions in the germanium-cobalt test solution were calculated based on the standard working curves of germanium and cobalt concentrations, respectively. Then the germanium content and cobalt content in the silver-copper alloy were calculated. The formula for calculating the germanium or cobalt content in silver-copper alloys is as follows: ; Where: W% - mass fraction of germanium or cobalt content, %; C - concentration of germanium or cobalt after subtracting blank from the measured concentration, µg / mL; V - volume of germanium-cobalt test solution, mL; m - weight of silver-copper alloy, g; The results of 11 measurements (germanium and cobalt content in the silver-copper alloy) for sample #3 of this embodiment, along with the average value and relative standard deviation, are shown in Table 3. Table 3. Determination results of germanium and cobalt content, average values, and relative standard deviations of silver-copper alloy sample #3. ; As shown in Table 3, the digestion effect of the silver-copper sample in this embodiment is good, germanium does not volatilize, the measurement results are stable, the relative standard deviation of germanium is 0.96% and cobalt is 1.54%, which improves the accuracy of the determination of germanium and cobalt content in silver-copper alloy.
[0016] Example 4: Eleven measurements were performed on silver-copper alloy sample #4 with a standard germanium content of 12.0% (mass fraction) and a standard cobalt content of 5.0% (mass fraction), and the average value and relative standard deviation were calculated. A method for determining the germanium and cobalt content in a silver-copper alloy, the specific steps of which are as follows: (1) Accurately weighed La2O3 (accurate to 0.0001 g) was added to commercially available nitric acid solution and heated to dissolve. After cooling, the solution was diluted to 500 mL with deionized water to obtain lanthanum internal standard solution. The concentration of lanthanum in the lanthanum internal standard solution was 2 mg / mL. (2) Add the silver-copper alloy (accurate to 0.0001 g) to a dilute nitric acid solution, digest it at 150 °C, and cool it to room temperature to obtain the digestion solution; the concentration of the dilute nitric acid solution is 7.94 mol / L, and the mass ratio of dilute nitric acid to silver-copper alloy is 60:1; (3) Add a small amount of hydrobromic acid to the digestion solution to generate AgBr precipitate of silver ions, and boil at 130°C until the solution is clear. Separate the solid and liquid to obtain the filtrate, add lanthanum internal standard solution to the filtrate, and dilute with deionized water to obtain germanium-cobalt test solution; the amount of lanthanum internal standard solution added to 100mL of germanium-cobalt test solution is 1mL. (4) Add commercially available nitric acid and hydrobromic acid to a volumetric flask, accurately transfer germanium-cobalt standard stock solution, and prepare germanium-cobalt standard working solutions with concentrations of 0.00, 1.00 µg / mL, 5.00 µg / mL, 10.00 µg / mL, 25.00 µg / mL, and 50.00 µg / mL, respectively. Add lanthanum internal standard solution to each germanium-cobalt standard working solution. The concentration of hydrobromic acid is 0.12 mol / L. The amount of commercially available nitric acid added to 100 mL of germanium-cobalt standard working solution is 7 mL, the amount of hydrobromic acid added is 1 mL, and the amount of lanthanum internal standard solution added is 1 mL. (5) The output spectral intensities of several germanium and cobalt standard working solutions were measured using an inductively coupled plasma atomic emission spectrometer (wavelength: 303.906 nm for germanium and 236.380 nm for cobalt), and standard working curves for germanium concentration were established respectively (see Figure 1 ) and cobalt concentration standard working curve (see Figure 2 ); (6) The output spectral intensity of the germanium-cobalt test solution was measured by an inductively coupled plasma atomic emission spectrometer (wavelength: 303.906 nm for germanium and 236.380 nm for cobalt). The concentrations of germanium ions and cobalt ions in the germanium-cobalt test solution were calculated based on the standard working curves of germanium and cobalt concentrations, respectively. Then the germanium content and cobalt content in the silver-copper alloy were calculated. The formula for calculating the germanium or cobalt content in silver-copper alloys is as follows: ; Where: W% - mass fraction of germanium or cobalt content, %; C - concentration of germanium or cobalt after subtracting blank from the measured concentration, µg / mL; V - volume of germanium-cobalt test solution, mL; m - weight of silver-copper alloy, g; The results of 11 measurements (germanium and cobalt content in the silver-copper alloy) for sample #4 of this embodiment, along with the average value and relative standard deviation, are shown in Table 4. Table 4. Determination results of germanium and cobalt content, average values, and relative standard deviations of silver-copper alloy sample #4. ; As shown in Table 4, the digestion effect of the silver-copper sample in this embodiment is good, germanium does not volatilize, the measurement results are stable, and the relative standard deviations are only 0.44% for germanium and 0.93% for cobalt, which improves the accuracy of the determination of germanium and cobalt content in silver-copper alloy.
[0017] The specific embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.
Claims
1. A method for determining the cobalt content of germanium in a silver-copper alloy, characterized by, The specific steps are as follows: (1) accurately weighed La2O3 is added to commercially available nitric acid and heated to dissolve, and after cooling, deionized water is added to constant volume to obtain a lanthanum internal standard solution; (2) the silver-copper alloy is added to a dilute nitric acid solution and digested at a temperature of 130-150 DEG C, and after cooling to room temperature, a digestion solution is obtained; (3) hydrobromic acid is added to the digestion solution to form AgBr precipitate from silver ions, and the solution is boiled at a temperature of 110-130 DEG C until it is clear, and the filtrate is obtained by solid-liquid separation, and the lanthanum internal standard solution is added to the filtrate, and deionized water is added to constant volume to obtain a germanium-cobalt test solution; (4) commercially available nitric acid and hydrobromic acid are added to a volumetric flask, and the germanium-cobalt standard stock solution is accurately transferred, and the germanium-cobalt standard working solutions with concentrations of 0.00, 1.00 µg / mL, 5.00 µg / mL, 10.00 µg / mL, 25.00 µg / mL and 50.00 µg / mL are prepared respectively, and the lanthanum internal standard solution is added to the germanium-cobalt standard working solutions; (5) the output spectral intensity of several germanium-cobalt standard working solutions is measured by an inductively coupled plasma emission spectrometer, and the germanium concentration standard working curve and the cobalt concentration standard working curve are established respectively; (6) the output spectral intensity of the germanium-cobalt test solution is measured by an inductively coupled plasma emission spectrometer, and the germanium ion concentration and the cobalt ion concentration in the germanium-cobalt test solution are calculated according to the germanium concentration standard working curve and the cobalt concentration standard working curve respectively, and then the germanium content and the cobalt content in the silver-copper alloy are calculated.
2. The method for determining the content of cobalt and germanium in silver-copper alloy according to claim 1, characterized in that: In step (1), the lanthanum concentration in the lanthanum internal standard solution is 2 mg / mL.
3. The method for determining the content of cobalt and germanium in silver-copper alloy according to claim 1, characterized in that: In step (2), the dilute nitric acid solution has a concentration of 4.00-7.94 mol / L, and the mass ratio of dilute nitric acid to silver-copper alloy is 20-60:
1.
4. The method for determining the content of cobalt and germanium in silver-copper alloy according to claim 1, characterized in that: In step (3), the germanium content in the germanium-cobalt test solution is 0.001-0.05 mg / mL, the cobalt content is 0.001-0.05 mg / mL, and the addition amount of the lanthanum internal standard solution in 100 mL of the germanium-cobalt test solution is 1 mL.
5. The method for determining the content of cobalt and germanium in silver-copper alloy according to claim 1, characterized in that: In step (4), the concentration of hydrobromic acid is 0.12-0.37 mol / L, the addition amount of commercially available nitric acid in 100 mL of the germanium-cobalt standard working solution is 3-7 mL, the addition amount of hydrobromic acid is 1-3 mL, and the addition amount of the lanthanum internal standard solution is 1 mL.
6. The method for determining the content of cobalt and germanium in silver-copper alloy according to claim 1, characterized in that: Step (6) The calculation formula of the content of germanium or cobalt in silver-copper alloy is: ; In the formula, W%-mass fraction of the germanium or cobalt content, %; C-measured concentration of germanium or cobalt after deducting the blank, µg / mL; V-constant volume of the germanium-cobalt test solution, mL; m-weight of the silver-copper alloy, g.