Ferrite corrosion method

Abstract

The invention discloses a ferrite corrosion method, which adopts a composite corrosive liquid system and a staged corrosion process to effectively corrode and decompose a ferrite material with high stability, realizes controllable full dissolution of garnet type, spinel type and hexagonal system ferrites within 2.5-3.5 hours, effectively supports wet etching of the ferrites and improves the corrosion performance of the ferrites. The high-precision processing of the ferrite material is realized, so that the ferrite material can be manufactured into a more complex and fine structure, the electromagnetic performance of the ferrite material is optimized, and the ferrite material can be widely applied to the field of micro-nano processing.

Description

Technical Field

[0001] The invention relates to the technical field of ferrite materials, and in particular to a ferrite corrosion method. Background Art

[0002] Ferrite is a composite oxide composed of iron and one or more other metal elements. It is a ferrimagnetic material with garnet, spinel and hexagonal crystal structures. The combination of iron, oxygen and other metal elements gives ferrite a unique structural property, in which metal cations occupy specific lattice positions; this orderly arrangement makes ferrite have high chemical and thermal stability, making it not easily corroded by acid.

[0003] In scientific research testing, spectral testing usually requires samples to be prepared into solutions, and the test accuracy is higher after the volume is fixed. For example, inductively coupled plasma spectrometer (ICP) can quantitatively analyze the ppm-level element content in the sample, but the test sample is required to be about 10mL of clear solution. However, for corrosion-resistant materials such as ferrite, existing corrosion methods are difficult to effectively prepare samples, resulting in the inability to accurately determine the sample elements.

[0004] Therefore, a ferrite corrosion method is urgently needed to solve the problem that ferrite is difficult to corrode or corrodes slowly in the prior art. Summary of the invention

[0005] The purpose of the present invention is to provide a ferrite corrosion method in order to solve the above problems. The present invention configures a corrosion liquid to effectively corrode and decompose ferrite materials with high stability, thereby providing assistance for subsequent ferrite surface processing and element testing and analysis.

[0006] The present invention achieves the above-mentioned purpose through the following technical solutions:

[0007] A ferrite corrosion method comprises the following steps:

[0008] Step 1, placing the ferrite material in a corrosive solution and heating it at 70-90°C;

[0009] Step 2, stop heating after white attachment appears on the surface of the ferrite material, and add hydrochloric acid;

[0010] Step 3, continue heating until the white attachment on the surface of the ferrite material disappears, then stop heating, add a mixture of sulfuric acid and hydrogen peroxide, and heat again;

[0011] Step 4: Repeat steps 2 and 3 until the material is completely dissolved.

[0012] A further solution is that in the step 1, the etching solution is composed of a mixed solution with a volume ratio of sulfuric acid, hydrogen peroxide and deionized water of 1-3:1:1-2.

[0013] A further solution is that in the step 1, the sulfuric acid is a sulfuric acid solution with a mass fraction of 10-30%, and the hydrogen peroxide is a hydrogen peroxide solution with a mass fraction of 20-30%;

[0014] A further solution is that in the step 1, the volume ratio of the etching solution to the ferrite material is not less than 15000:1.

[0015] A further solution is that in the step 1, the ferrite material is a garnet-type, spinel-type or hexagonal ferrite material.

[0016] A further solution is that in the step 2, the volume ratio of hydrochloric acid to sulfuric acid in the etching solution in step 1 is 1-2:1, and the mass fraction of the hydrochloric acid is 36%-38%.

[0017] A further solution is that in the step 3, the volume ratio of sulfuric acid to hydrogen peroxide is 1-3:1.

[0018] A further solution is that in the step 3, the volume ratio of the mixed solution to the ferrite material is not less than 5000:1.

[0019] The beneficial effects of the present invention are as follows:

[0020] A method for etching a ferrite of the present invention effectively etches and decomposes a ferrite material with high stability by adopting a composite etching solution system and a staged etching process, realizes the controllable complete dissolution of garnet-type, spinel-type and hexagonal ferrites within 2.5-3.5 hours, effectively supports the wet etching of ferrites, realizes the high-precision processing of ferrite materials, enables the production of more complex and delicate structures, optimizes their electromagnetic properties, and enables ferrites to be more widely used in the field of micro-nano processing. Detailed implementation manners

[0021] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be described in detail below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other implementation manners obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

[0022] Example 1:

[0023] 1. Clean a garnet-type ferrite material with a volume of 5×5×0.5 mm with deionized water;

[0024] 2. Then, prepare 200 ml of a dilute acid etching solution with a volume ratio of sulfuric acid: hydrogen peroxide: water = 1:1:1.

[0025] 3. Place the cleaned garnet-type ferrite material into the dilute acid etching solution, and then put the dilute acid etching solution into a water bath heating device. Set the water bath temperature to 70 °C and start heating.

[0026] 4. Observe that bubbles are generated on the surface of the material, and a white attachment appears, completely covering the surface of the material. Stop the water bath heating, and at the same time, add hydrochloric acid with a volume ratio of hydrochloric acid: sulfuric acid = 1:1, and then continue heating.

[0027] 5. Observe that the white attachment on the surface of the material disappears. Stop the water bath heating, add 70 ml of a solution with a volume ratio of sulfuric acid: hydrogen peroxide = 1:1, and then heat again.

[0028] 6. Repeat steps 4 and 5 three times, and the material will be completely dissolved. The whole process takes 2.5 - 3.5 hours.

[0029] Example 2:

[0030] Replace the material in Example 1 with a spinel material with a volume of 5 × 5 × 0.5 mm, and operate according to the method in Example 1. The spinel material is completely dissolved, and the whole process takes about 2.5 - 3.5 hours.

[0031] Example 3:

[0032] Replace the material in Example 1 with a hexagonal crystal system material with a volume of 5 × 5 × 0.5 mm, and operate according to the method in Example 1. The hexagonal crystal system material is completely dissolved, and the whole process takes about 2.5 - 3.5 hours.

[0033] Example 4:

[0034] Set the water bath temperature in Example 1 to 90 °C, and operate according to the method in Example 1. The garnet-type ferrite material is completely dissolved, and the whole process takes about 1.5 - 2.5 hours.

[0035] Comparative Example 1:

[0036] Replace the sulfuric acid in Example 1 with nitric acid, and keep the others unchanged. After operating, it is found that no bubbles appear on the surface of the material, the corrosion phenomenon is not obvious, and the sample is taken out after 6 hours, and the volume of the sample remains basically unchanged.

[0037] Comparative Example 2:

[0038] The sulfuric acid in Example 1 was replaced with phosphoric acid, and the other conditions remained unchanged. The operation was carried out and bubbles appeared on the surface of the material. The material was corroded, but the solution became viscous and white reactants appeared at the bottom of the reaction vessel, which was difficult to remove. The sample was taken out after 6 hours. The edges and corners of the sample disappeared, but there were still large pieces of sample that were not corroded.

[0039] Comparative Example 3:

[0040] Ferrite was corroded according to the method in Example 1, except that sulfuric acid: hydrogen peroxide was adjusted to 4:1. White attachments quickly appeared on the surface of the material, hindering the reaction. Hydrochloric acid had to be added frequently to keep the reaction going. The overall controllability of the process was poor, and personnel had to be stationed to observe the entire process.

[0041] Comparative Example 4:

[0042] Ferrite was corroded according to the method in Example 1, except that the water bath temperature was set to 60° C., the reaction was slower, the overall dissolution time was longer, and the sample was completely dissolved after 6-6.5 hours.

[0043] Comparative Example 5:

[0044] The ferrite was corroded according to the method in Example 1, except that the water bath temperature was set to 100° C., the acid liquid boiled, and there was acid liquid splashing out, which had poor safety and was not suitable for long-term heating.

[0045] In the above embodiments and comparative examples, sulfuric acid is a sulfuric acid solution with a mass fraction of 30%, hydrogen peroxide is a hydrogen peroxide solution with a mass fraction of 30%; the mass fraction of hydrochloric acid is 36%-38%; the mass fraction of nitric acid is 65%, and the mass fraction of phosphoric acid is 85%.

[0046] Since the timing of replenishing the acid solution is different, the reaction time of the embodiments and comparative examples of the present application is a range value.

[0047] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or replacements within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims. It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further explain various possible combinations. In addition, the various different embodiments of the present invention can also be combined arbitrarily, as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A method for corroding ferrite, characterized in that, It includes the following steps: Step 1: Place the ferrite material in the etching solution and heat it at 70 - 90 °C; Step 2: Stop heating after white attachments appear on the surface of the ferrite material, and add hydrochloric acid; Step 3: Continue heating until the white attachments on the surface of the ferrite material disappear, then stop heating, add a mixed solution of sulfuric acid and hydrogen peroxide, and heat again; Step 4: Repeat Step 2 - Step 3 until the material is completely dissolved.

2. The corrosion method of a ferrite according to claim 1, characterized in that In Step 1, the etching solution is composed of a mixed solution with a volume ratio of sulfuric acid, hydrogen peroxide, and deionized water of 1 - 3:1:1 - 2.

3. The corrosion method of a ferrite according to claim 2, characterized in that, In Step 1, the sulfuric acid is a sulfuric acid solution with a mass fraction of 10 - 30%, and the hydrogen peroxide is a hydrogen peroxide solution with a mass fraction of 30%.

4. The corrosion method of a ferrite according to claim 1, characterized in that In Step 1, the volume ratio of the etching solution to the ferrite material is not less than 15000:

1.

5. The corrosion method of a ferrite according to claim 1, characterized in that In Step 1, the ferrite material is garnet-type, spinel-type, or hexagonal ferrite material.

6. The corrosion method of a ferrite according to claim 1, characterized in that, In Step 2, the volume ratio of hydrochloric acid to sulfuric acid in the etching solution in Step 1 is 1 - 2:1, and the mass fraction of the hydrochloric acid is 36% - 38%.

7. The corrosion method of a ferrite according to claim 1, characterized in that, In Step 3, the volume ratio of sulfuric acid to hydrogen peroxide is 1 - 3:

1.

8. The corrosion method of a ferrite according to claim 1, characterized in that In Step 3, the volume ratio of the mixed solution to the ferrite material is not less than 5000:1.