Microwave digestion method of CoFeB alloy

Abstract

The invention provides a microwave digestion method of a CoFeB alloy, which comprises the following steps: mixing the CoFeB alloy and mixed acid, and then carrying out microwave digestion to complete the dissolution of the CoFeB alloy, the mixed acid is a combination of nitric acid and hydrochloric acid. According to the microwave digestion method, rapid dissolution of the CoFeB alloy can be achieved only by using the mixed acid composed of nitric acid and hydrochloric acid, the microwave digestion method does not need to use various acids, efficient microwave digestion of the CoFeB alloy can be achieved only through the single mixed acid, the convenience of ICP-OES sample preparation of the CoFeB alloy is improved, and the cost is reduced. And the accuracy of the obtained sample during ICP-OES detection is also improved.

Description

Technical Field

[0001] The invention belongs to the technical field of analysis and testing, and relates to a sample preparation method, in particular to a microwave digestion method for a CoFeB alloy. Background Art

[0002] ICP-OES refers to an inductively coupled plasma emission spectrometer. Its testing principle is to use an excitation light source to evaporate, dissociate or decompose the sample into an atomic state. The sample composition is analyzed based on the characteristic radiation energy emitted by the radiation transition when the gaseous atoms in the sample substance are excited and the outer electrons return to the ground state from the excited state. Therefore, the sample processing method for ICP-OES analysis is usually the solution atomization method. ICP-OES has high accuracy, but it cannot directly analyze and test solid samples. When converting solid samples into liquids, there is often a problem that the sample cannot be completely dissolved and enriched.

[0003] CN109211882A discloses a method for determining the boron content in low alloy steel by ICP-AES using a multi-acid dissolving sample, comprising the following steps: using nitric acid and hydrochloric acid to dissolve the sample at low temperature, using sulfuric acid, phosphoric acid and mannitol to digest carbon and prevent the volatilization of boron elements; using the same matrix standard boron solution as a working curve, and quickly determining the boron content in the low alloy steel at a wavelength of 249.677nm on an inductively coupled plasma atomic emission spectrometer (ICP-AES). The acid used is relatively large, and the dissolution process is complicated.

[0004] CoFeB alloy, as a soft magnetic alloy material, is widely used in magnetic tunnels and magnetic random access memories. The precise control of the composition of CoFeB alloy significantly affects the product quality when used for magnetron sputtering. Therefore, it is necessary to accurately detect the composition content of CoFeB alloy.

[0005] CN117405481A discloses a sample preparation method for ICP-OES analysis of CoFeB alloy, which comprises the following steps: mixing the CoFeB alloy with a first nitric acid and then heating it with a mixed acid, wherein the mixed acid comprises a second nitric acid and hydrochloric acid. Although the method can achieve the dissolution of CoFeB, the detection process is relatively cumbersome, and the measurement errors of Co, Fe and B elements are also large.

[0006] Therefore, it is necessary to provide a microwave digestion method for CoFeB alloy that is simple and accurate in measurement. Summary of the invention

[0007] In view of the shortcomings of the prior art, the object of the present invention is to provide a microwave digestion method for CoFeB alloy, which does not require the use of multiple acids and can achieve efficient microwave digestion of CoFeB alloy only by a single mixed acid, thereby realizing the ICP-OES sample preparation of CoFeB alloy.

[0008] To achieve this object, the present invention adopts the following technical solutions:

[0009] The present invention provides a microwave digestion method for CoFeB alloy, the microwave digestion method comprising the following steps:

[0010] Mixing the CoFeB alloy and the mixed acid, and then performing microwave digestion to complete the dissolution of the CoFeB alloy;

[0011] The mixed acid is a combination of nitric acid and hydrochloric acid.

[0012] The invention can realize the rapid dissolution of CoFeB alloy by microwave digestion using only a mixed acid consisting of nitric acid and hydrochloric acid. The microwave digestion method does not need to use multiple acids, and can realize the efficient microwave digestion of CoFeB alloy by only a single mixed acid, thereby improving the convenience of ICP-OES sample preparation of CoFeB alloy and the accuracy of ICP-OES detection of the obtained sample.

[0013] Preferably, the volume ratio of nitric acid to hydrochloric acid is 1:(2.5-3.5).

[0014] Preferably, the concentration of the nitric acid is 65-68 wt %.

[0015] Preferably, the concentration of the hydrochloric acid is 36-38 wt %.

[0016] Preferably, the microwave digestion includes a first microwave digestion, a second microwave digestion and a third microwave digestion with the temperatures increasing sequentially.

[0017] Preferably, the temperature of the first microwave digestion is 145-155°C.

[0018] Preferably, the first microwave digestion time is 8-12 min.

[0019] Preferably, the power of the first microwave digestion is 380-420W.

[0020] Preferably, the temperature of the second microwave digestion is 175-185°C.

[0021] Preferably, the second microwave digestion time is 14-16 min.

[0022] Preferably, the power of the second microwave digestion is 380-420W.

[0023] Preferably, the temperature of the third microwave digestion is 195-205°C.

[0024] Preferably, the third microwave digestion time is 38-42 min.

[0025] Preferably, the power of the third microwave digestion is 380-420W.

[0026] Preferably, the solid-liquid ratio of the CoFeB alloy to the mixed acid is 1:(7.5-8.5), and the unit of the solid-liquid ratio is g / mL.

[0027] As a preferred technical solution of the microwave digestion method provided by the present invention, the microwave digestion method comprises the following steps:

[0028] Mixing the CoFeB alloy and the mixed acid according to a solid-liquid ratio of 1:(7.5-8.5), and then performing microwave digestion to complete the dissolution of the CoFeB alloy, wherein the unit of the solid-liquid ratio is g / mL;

[0029] The mixed acid is a combination of nitric acid and hydrochloric acid in a volume ratio of 1:(2.5-3.5);

[0030] The concentration of the nitric acid is 65-68wt%, and the concentration of the hydrochloric acid is 36-38wt%;

[0031] The microwave digestion includes a first microwave digestion, a second microwave digestion and a third microwave digestion with the temperatures increasing in sequence;

[0032] The first microwave digestion is performed at a temperature of 145-155°C, a time of 8-12 minutes, and a power of 380-420W;

[0033] The second microwave digestion is performed at a temperature of 175-185°C, a time of 14-16 minutes, and a power of 380-420W;

[0034] The temperature of the third microwave digestion is 195-205°C, the time is 38-42 minutes, and the power is 380-420W.

[0035] The numerical range described in the present invention not only includes the point values ​​listed above, but also includes any point values ​​between the above numerical ranges that are not listed. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] The invention can realize the rapid dissolution of CoFeB alloy by microwave digestion using only a mixed acid consisting of nitric acid and hydrochloric acid. The microwave digestion method does not need to use multiple acids, and can realize the efficient microwave digestion of CoFeB alloy by only a single mixed acid, thereby improving the convenience of ICP-OES sample preparation of CoFeB alloy and the accuracy of ICP-OES detection of the obtained sample. DETAILED DESCRIPTION

[0038] The technical solution of the present invention is further illustrated below through specific implementation methods.

[0039] A certain embodiment of the present invention provides a microwave digestion method for CoFeB alloy, the microwave digestion method comprising the following steps:

[0040] Mixing the CoFeB alloy and the mixed acid, and then performing microwave digestion to complete the dissolution of the CoFeB alloy;

[0041] The mixed acid is a combination of nitric acid and hydrochloric acid.

[0042] The invention can realize the rapid dissolution of CoFeB alloy by microwave digestion using only a mixed acid consisting of nitric acid and hydrochloric acid. The microwave digestion method does not need to use multiple acids, and can realize the efficient microwave digestion of CoFeB alloy by only a single mixed acid, thereby improving the convenience of ICP-OES sample preparation of CoFeB alloy and the accuracy of ICP-OES detection of the obtained sample.

[0043] In some embodiments, the volume ratio of nitric acid to hydrochloric acid is 1:(2.5-3.5), for example, it can be 1:2.5, 1:2.8, 1:3, 1:3.2 or 1:3.5, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0044] In some embodiments, the concentration of nitric acid is 65-68wt%, for example, 65wt%, 66wt%, 67wt% or 68wt%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0045] In some embodiments, the concentration of the hydrochloric acid is 36-38wt%, for example, 36wt%, 36.5wt%, 37wt%, 37.5wt% or 38wt%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0046] In some embodiments, the microwave digestion includes a first microwave digestion, a second microwave digestion, and a third microwave digestion with successively increasing temperatures.

[0047] In certain embodiments, the temperature of the first microwave digestion is 145-155°C, for example, 145°C, 148°C, 150°C, 152°C or 155°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0048] In certain embodiments, the first microwave digestion time is 8-12 min, for example, 8 min, 9 min, 10 min, 11 min or 12 min, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0049] In some embodiments, the power of the first microwave digestion is 380-420 W, for example, 380 W, 390 W, 400 W, 410 W or 420 W, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0050] In certain embodiments, the temperature of the second microwave digestion is 175-185°C, for example, 175°C, 178°C, 180°C, 182°C or 185°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0051] In certain embodiments, the second microwave digestion time is 14-16 min, for example, 14 min, 14.5 min, 15 min, 15.5 min or 16 min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0052] In some embodiments, the power of the second microwave digestion is 380-420 W, for example, 380 W, 390 W, 400 W, 410 W or 420 W, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0053] In some embodiments, the temperature of the third microwave digestion is 195-205°C, for example, 195°C, 198°C, 200°C, 202°C or 205°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0054] In certain embodiments, the third microwave digestion time is 38-42 min, for example, 38 min, 39 min, 40 min, 41 min or 42 min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0055] In some embodiments, the power of the third microwave digestion is 380-420 W, for example, 380 W, 390 W, 400 W, 410 W or 420 W, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0056] In some embodiments, the solid-liquid ratio of the CoFeB alloy to the mixed acid is 1:(7.5-8.5), for example, it can be 1:7.5, 1:7.8, 1:8, 1:8.2 or 1:8.5, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable. The unit of the solid-liquid ratio is g / mL.

[0057] As a preferred technical solution of the microwave digestion method provided by the present invention, the microwave digestion method comprises the following steps:

[0058] Mixing the CoFeB alloy and the mixed acid according to a solid-liquid ratio of 1:(7.5-8.5), and then performing microwave digestion to complete the dissolution of the CoFeB alloy, wherein the unit of the solid-liquid ratio is g / mL;

[0059] The mixed acid is a combination of nitric acid and hydrochloric acid in a volume ratio of 1:(2.5-3.5);

[0060] The concentration of the nitric acid is 65-68wt%, and the concentration of the hydrochloric acid is 36-38wt%;

[0061] The microwave digestion includes a first microwave digestion, a second microwave digestion and a third microwave digestion with the temperatures increasing in sequence;

[0062] The first microwave digestion is performed at a temperature of 145-155°C, a time of 8-12 minutes, and a power of 380-420W;

[0063] The second microwave digestion is performed at a temperature of 175-185°C, a time of 14-16 minutes, and a power of 380-420W;

[0064] The temperature of the third microwave digestion is 195-205°C, the time is 38-42 minutes, and the power is 380-420W.

[0065] In order to clearly illustrate the technical solution of the present invention, the Co content of the CoFeB alloy in the following specific implementation manner is 63wt%, the Fe content is 32wt%, and the B content is 5wt%.

[0066] Example 1

[0067] This embodiment provides a microwave digestion method for CoFeB alloy, and the microwave digestion method comprises the following steps:

[0068] Take 0.1 g of CoFeB alloy, mix the CoFeB alloy and mixed acid according to a solid-liquid ratio of 1:8, and then perform microwave digestion to complete the dissolution of the CoFeB alloy, wherein the unit of the solid-liquid ratio is g / mL;

[0069] The mixed acid is a combination of nitric acid and hydrochloric acid in a volume ratio of 1:3;

[0070] The concentration of the nitric acid is 66wt%, and the concentration of the hydrochloric acid is 37wt%;

[0071] The microwave digestion includes a first microwave digestion, a second microwave digestion and a third microwave digestion with the temperatures increasing in sequence;

[0072] The first microwave digestion was performed at a temperature of 150°C, a time of 10 min, and a power of 400 W;

[0073] The second microwave digestion was performed at a temperature of 180°C, a time of 15 min, and a power of 400 W;

[0074] The temperature of the third microwave digestion is 200° C., the time is 40 min, and the power is 400W.

[0075] Example 2

[0076] This embodiment provides a microwave digestion method for CoFeB alloy, and the microwave digestion method comprises the following steps:

[0077] Take 0.1 g of CoFeB alloy, mix the CoFeB alloy and mixed acid according to a solid-liquid ratio of 1:7.5, and then perform microwave digestion to complete the dissolution of the CoFeB alloy, wherein the unit of the solid-liquid ratio is g / mL;

[0078] The mixed acid is a combination of nitric acid and hydrochloric acid in a volume ratio of 1:2.5;

[0079] The concentration of the nitric acid is 65wt%, and the concentration of the hydrochloric acid is 36wt%;

[0080] The microwave digestion includes a first microwave digestion, a second microwave digestion and a third microwave digestion with the temperatures increasing in sequence;

[0081] The first microwave digestion was performed at a temperature of 145°C, a time of 12 min, and a power of 380 W;

[0082] The second microwave digestion was performed at a temperature of 175°C, a time of 16 min, and a power of 380 W;

[0083] The temperature of the third microwave digestion is 195° C., the time is 42 min, and the power is 380W.

[0084] Example 3

[0085] This embodiment provides a microwave digestion method for CoFeB alloy, and the microwave digestion method comprises the following steps:

[0086] Take 0.1 g of CoFeB alloy, mix the CoFeB alloy and mixed acid according to a solid-liquid ratio of 1:8.5, and then perform microwave digestion to complete the dissolution of the CoFeB alloy, wherein the unit of the solid-liquid ratio is g / mL;

[0087] The mixed acid is a combination of nitric acid and hydrochloric acid in a volume ratio of 1:3.5;

[0088] The concentration of the nitric acid is 68wt%, and the concentration of the hydrochloric acid is 38wt%;

[0089] The microwave digestion includes a first microwave digestion, a second microwave digestion and a third microwave digestion with the temperatures increasing in sequence;

[0090] The first microwave digestion was performed at a temperature of 155°C, a time of 8 min, and a power of 420 W;

[0091] The second microwave digestion was performed at a temperature of 185°C, a time of 14 min, and a power of 420 W;

[0092] The temperature of the third microwave digestion is 205° C., the time is 38 min, and the power is 420W.

[0093] Example 4

[0094] This embodiment provides a microwave digestion method for CoFeB alloy, which is the same as that of Embodiment 1 except that the temperature of the first microwave digestion is 140°C.

[0095] Example 5

[0096] This embodiment provides a microwave digestion method for CoFeB alloy, which is the same as that of Embodiment 1 except that the temperature of the first microwave digestion is 170°C.

[0097] Example 6

[0098] This embodiment provides a microwave digestion method for CoFeB alloy, which is the same as that of Embodiment 1 except that the temperature of the first microwave digestion is 190°C.

[0099] Example 7

[0100] This embodiment provides a microwave digestion method for CoFeB alloy, which is the same as that of Embodiment 1 except that the first microwave digestion is not performed.

[0101] Example 8

[0102] This embodiment provides a microwave digestion method for CoFeB alloy, which is the same as that of Embodiment 1 except that the second microwave digestion is not performed.

[0103] Example 9

[0104] This embodiment provides a microwave digestion method for CoFeB alloy, which is the same as that of Embodiment 1 except that the third microwave digestion is not performed.

[0105] Example 10

[0106] This embodiment provides a microwave digestion method for CoFeB alloy, which is the same as that of Embodiment 1 except that the volume ratio of nitric acid to hydrochloric acid in the mixed acid is 1:2.

[0107] Embodiment 11

[0108] This embodiment provides a microwave digestion method for CoFeB alloy, which is the same as that of Embodiment 1 except that the volume ratio of nitric acid to hydrochloric acid in the mixed acid is 1:4.

[0109] Comparative Example 1

[0110] This comparative example provides a microwave digestion method for CoFeB alloy, which is the same as Example 1 except that an equal volume of nitric acid in the mixed acid is replaced by hydrochloric acid.

[0111] Comparative Example 2

[0112] This comparative example provides a microwave digestion method for CoFeB alloy, which is the same as Example 1 except that an equal volume of hydrochloric acid in the mixed acid is replaced by nitric acid.

[0113] Performance Characterization

[0114] The sample solutions of the above embodiments and comparative examples that were digested by microwave were subjected to element content determination on ICP-OES. The reference spectrum line of Co was 238.892 nm, the reference spectrum line of Fe was 238.204 nm, and the reference spectrum line of B was 249.772 nm. The results are shown in Table 1.

[0115] Table 1

[0116]

[0117] In summary, the present invention can achieve rapid dissolution of CoFeB alloy by microwave digestion using only a mixed acid consisting of nitric acid and hydrochloric acid. The microwave digestion method does not require the use of multiple acids, and efficient microwave digestion of CoFeB alloy can be achieved only by a single mixed acid, thereby improving the convenience of ICP-OES sample preparation of CoFeB alloy and the accuracy of ICP-OES detection of the obtained sample.

[0118] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A microwave digestion method for CoFeB alloy, characterized in that: The microwave digestion method comprises the following steps: Mixing the CoFeB alloy and the mixed acid, and then performing microwave digestion to complete the dissolution of the CoFeB alloy; The mixed acid is a combination of nitric acid and hydrochloric acid.

2. The microwave digestion method according to claim 1, characterized in that: The volume ratio of the nitric acid to the hydrochloric acid is 1:(2.5-3.5).

3. The microwave digestion method according to claim 1 or 2, characterized in that: The concentration of the nitric acid is 65-68 wt %.

4. The microwave digestion method according to any one of claims 1 to 3, characterized in that: The concentration of the hydrochloric acid is 36-38 wt %.

5. The microwave digestion method according to any one of claims 1 to 4, characterized in that: The microwave digestion includes a first microwave digestion, a second microwave digestion and a third microwave digestion with the temperatures rising in sequence.

6. The microwave digestion method according to claim 5, characterized in that: The temperature of the first microwave digestion is 145-155°C; Preferably, the first microwave digestion time is 8-12 min; Preferably, the power of the first microwave digestion is 380-420W.

7. The microwave digestion method according to claim 5, characterized in that: The temperature of the second microwave digestion is 175-185°C; Preferably, the second microwave digestion time is 14-16 min; Preferably, the power of the second microwave digestion is 380-420W.

8. The microwave digestion method according to claim 5, characterized in that: The temperature of the third microwave digestion is 195-205°C; Preferably, the third microwave digestion time is 38-42 min; Preferably, the power of the third microwave digestion is 380-420W.

9. The microwave digestion method according to any one of claims 1 to 8, characterized in that: The solid-liquid ratio of the CoFeB alloy to the mixed acid is 1:(7.5-8.5), and the unit of the solid-liquid ratio is g / mL.

10. The microwave digestion method according to any one of claims 1 to 9, characterized in that: The microwave digestion method comprises the following steps: Mixing the CoFeB alloy and the mixed acid according to a solid-liquid ratio of 1:(7.5-8.5), and then performing microwave digestion to complete the dissolution of the CoFeB alloy, wherein the unit of the solid-liquid ratio is g / mL; The mixed acid is a combination of nitric acid and hydrochloric acid in a volume ratio of 1:(2.5-3.5); The concentration of the nitric acid is 65-68wt%, and the concentration of the hydrochloric acid is 36-38wt%; The microwave digestion includes a first microwave digestion, a second microwave digestion and a third microwave digestion with the temperatures increasing in sequence; The first microwave digestion is performed at a temperature of 145-155°C, a time of 8-12 minutes, and a power of 380-420W; The second microwave digestion is performed at a temperature of 175-185°C, a time of 14-16 minutes, and a power of 380-420W; The temperature of the third microwave digestion is 195-205°C, the time is 38-42 minutes, and the power is 380-420W.

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