CN112695325A

CN112695325A - Nickel-containing polishing agent, aluminum piece and polishing treatment method thereof

Info

Publication number: CN112695325A
Application number: CN202011460869.6A
Authority: CN
Inventors: 刘国平
Original assignee: Shenzhen Hongchangfa Technology Co Ltd
Current assignee: Shenzhen Hongchangfa Technology Co Ltd
Priority date: 2020-12-11
Filing date: 2020-12-11
Publication date: 2021-04-23

Abstract

The invention relates to a nickel-containing polishing agent, an aluminum piece and a polishing treatment method thereof. The nickel-containing polishing agent is used for surface pretreatment of aluminum parts and comprises the following components in parts by weight based on 100 parts by weight: 3-10 parts of nitric acid, 0.005-0.02 part of copper nitrate, 5-10 parts of chromic anhydride, 20-50 parts of phosphoric acid, 5-12 parts of aluminum phosphate, 0.5-3 parts of nickel nitrate and the balance of water. After the nickel-containing polishing agent is used for treating, the surface of an aluminum piece is clean and bright, and the whole polishing treatment method is simple in process equipment, convenient to operate and low in use cost, and can treat workpieces with complex shapes.

Description

Nickel-containing polishing agent, aluminum piece and polishing treatment method thereof

Technical Field

The invention relates to the technical field of iron surface treatment, in particular to a nickel-containing polishing agent, an aluminum piece and a polishing treatment method thereof.

Background

In order to improve the surface properties or appearance of the product, the surface of the workpiece is usually treated. For example, surface treatment processes for stainless steel, zinc alloys, aluminum, and the like, and alloys thereof, are in great popularity. Furthermore, most workpieces are also subjected to a pretreatment, such as cleaning, desmutting, or degreasing, prior to surface treatment, and some metal workpieces are also subjected to a polishing treatment.

Generally, in the mechanical processing and electronic and electrical industries, the cleaning and polishing treatment, i.e., polishing treatment, of aluminum parts is common. Conventional nickel-containing polishes are typically polished using mechanical polishing, which is poor for complex workpiece geometries and is prone to cracking and scratching, or three-acid polishing. The triacid in the triacid polishing, namely concentrated nitric acid, concentrated sulfuric acid and concentrated phosphoric acid, reacts violently under the high-temperature condition, gas is volatilized greatly, and a large amount of NO can be generated_XGas is unsafe, has great harm to the environment and large energy consumption.

Disclosure of Invention

In view of the above, a nickel-containing polishing agent with better physical appearance, higher mechanical properties, better corrosion resistance, easy cleaning, special effect, less odor and less energy consumption, a polishing method for aluminum parts and an aluminum part prepared by polishing are provided.

A nickel-containing polishing agent comprises the following components in parts by weight based on 100 parts by weight: 3-10 parts of nitric acid, 0.005-0.02 part of copper nitrate, 5-10 parts of chromic anhydride, 20-50 parts of phosphoric acid, 5-12 parts of aluminum phosphate, 0.5-3 parts of nickel nitrate and the balance of water.

An aluminum piece polishing treatment method comprises the following steps: formulating a nickel containing polish as described above; and (3) immersing the aluminum piece into a polishing agent solution, and washing the aluminum piece with water after the aluminum piece is treated at preset time and temperature.

And an aluminum member, the surface of which is polished by the aluminum member polishing treatment method as described above.

After the nickel-containing polishing agent is used for processing, the surface of an aluminum piece has high light reflectivity and no defects of pitting, spots, white mist and the like, and the whole polishing processing method has the advantages of simple process, small smell, convenience in operation and low use cost.

Detailed Description

The present invention will be described in detail with reference to specific examples.

The embodiment of the invention provides a nickel-containing polishing agent for surface pretreatment of an aluminum piece, which comprises the following components in parts by weight based on 100 parts by weight: 3-10 parts of nitric acid, 0.005-0.02 part of copper nitrate, 5-10 parts of chromic anhydride, 20-50 parts of phosphoric acid, 5-12 parts of aluminum phosphate, 0.5-3 parts of nickel nitrate and the balance of water.

Specifically, the weight part of the nitric acid is preferably 5 to 8 parts. The weight portion of the copper nitrate is preferably 0.01-0.02 part, the weight portion of the chromic anhydride is preferably 6-8 parts, and the weight portion of the phosphoric acid is preferably 30-50 parts. The aluminum phosphate is preferably 6-10 parts by weight, and the nickel nitrate is preferably 1-2 parts by weight.

In the chemical etching process, the microscopic projections on the metal surface are in solution and the dissolution rate is much greater than that of the microscopic depressions, resulting in a gradually leveled and smooth, shiny surface. The proportion of each component is controlled to be balanced, so that a better polishing effect is achieved. The nitric acid, the chromic anhydride and the phosphoric acid remove oxide skins and enable the surface of the aluminum to react quickly, wherein the chromic anhydride and the nitric acid increase oxidability so as to accelerate the reaction, the aluminum phosphate increases the viscosity of the solution, the diffusion speed of the aluminum phosphate at the microcosmic convex part of the workpiece is much faster than that of the microcosmic concave part, and therefore the reaction speed of the microcosmic concave part is reduced, and the effect of leveling the surface is achieved. The nickel nitrate can effectively avoid the difficulty in reaction due to the excessive aluminum phosphate. Copper nitrate can improve the reflectivity of the aluminum alloy.

The embodiment of the invention also provides an aluminum piece polishing treatment method, which comprises the following steps: formulating a nickel containing polish as described above; and immersing the aluminum piece into a polishing agent solution, washing the aluminum piece with water after a preset time, and drying.

Specifically, the predetermined time is 0.5 to 3 minutes. Further, after polishing, passivation or oxidation is performed, and then washing and drying are performed. During polishing treatment, the temperature is controlled at 60-100 ℃. Furthermore, pretreatment such as degreasing, degreasing and descaling is performed before polishing.

The embodiment of the invention also provides the aluminum piece, which is polished by the aluminum piece polishing method, so that the aluminum piece forms a clean and bright surface. After the nickel-containing polishing agent is used for processing, the surface of an aluminum piece is clean, the light reflectivity is high, and the whole polishing processing method is simple in process, convenient to operate and low in use cost. The aluminum piece is made of aluminum or aluminum alloy and is made of various profiles or workpieces.

Specifically, the following examples are given in the following examples of Al-Mg alloys with 99.99 mass% aluminum, since the composition of aluminum alloys greatly affects the surface brightness after chemical polishing, and generally, the higher the purity of aluminum, the better the polishing brightness

Example 1

The following components are mixed according to the following parts by weight (the total weight is 100 parts by weight): 3 parts of nitric acid, 0.005 part of copper nitrate, 5 parts of chromic anhydride, 20 parts of phosphoric acid, 5 parts of aluminum phosphate, 0.5 part of nickel nitrate and the balance of water.

The treatment method comprises the following steps: preparing a nickel-containing polishing agent; deoiling and descaling an aluminum piece in advance, then washing with water, immersing the workpiece with a clean surface into a polishing agent solution at 85 ℃, washing with water after 3 minutes, and drying.

After the polishing agent solution is used for processing, the surface of a workpiece is observed, and the whole surface is clean and bright and has consistent color and no abnormity such as spots, white fog, pitting corrosion and the like. The specular reflectivity is more than 40%.

Example 2

The following components are mixed according to the following parts by weight (the total weight is 100 parts by weight): 5 parts of nitric acid, 0.01 part of copper nitrate, 7 parts of chromic anhydride, 30 parts of phosphoric acid, 7 parts of aluminum phosphate, 1 part of nickel nitrate and the balance of water.

The treatment method comprises the following steps: preparing a nickel-containing polishing agent; the aluminum piece is degreased and descaled in advance, then washed, and then the workpiece with a clean surface is immersed into a polishing agent solution at 85 ℃, and after 2 minutes, washed and dried.

After the polishing agent solution is used for processing, the surface of a workpiece is observed, and the whole surface is clean and bright and has consistent color and no abnormity such as spots, white fog, pitting corrosion and the like. The specular reflectivity is more than 50%.

Example 3

The following components are mixed according to the following parts by weight (the total weight is 100 parts by weight): 8 parts of nitric acid, 0.015 part of copper nitrate, 8 parts of chromic anhydride, 40 parts of phosphoric acid, 10 parts of aluminum phosphate, 2 parts of nickel nitrate and the balance of water.

After the polishing agent solution is used for processing, the surface of a workpiece is observed, and the whole surface is clean and bright and has consistent color and no abnormity such as spots, white fog, pitting corrosion and the like. The specular reflectivity is more than 60%.

Example 4

The following components are mixed according to the following parts by weight (the total weight is 100 parts by weight): 10 parts of nitric acid, 0.02 part of copper nitrate, 10 parts of chromic anhydride, 50 parts of phosphoric acid, 12 parts of aluminum phosphate, 3 parts of nickel nitrate and the balance of water.

The treatment method comprises the following steps: preparing a nickel-containing polishing agent; deoiling and descaling an aluminum piece in advance, then washing with water, immersing the workpiece with a clean surface into a polishing agent solution at 85 ℃, washing with water after 1.5 minutes, and drying.

After the polishing agent solution is used for processing, the surface of a workpiece is observed, and the whole surface is clean and bright and has consistent color and no abnormity such as spots, white fog, pitting corrosion and the like. The specular reflectivity is more than 80%.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and other changes and modifications can be made by those skilled in the art according to the spirit of the present invention, and these changes and modifications made according to the spirit of the present invention should be included in the scope of the present invention as claimed.

Claims

1. A nickel-containing polishing agent is characterized by comprising the following components in parts by weight based on 100 parts by weight: 3-10 parts of nitric acid, 0.005-0.02 part of copper nitrate, 5-10 parts of chromic anhydride, 20-50 parts of phosphoric acid, 5-12 parts of aluminum phosphate, 0.5-3 parts of nickel nitrate and the balance of water.

2. The nickel-containing polish of claim 1 wherein the weight fraction of nitric acid is 5 to 8 parts.

3. The nickel containing polish of claim 1 wherein the weight fraction of said copper nitrate is 0.01 to 0.02 parts.

4. The nickel containing polish of claim 1 wherein the weight fraction of said chromic anhydride is 6 to 8 parts.

5. The nickel containing polish of claim 1 wherein the weight fraction of phosphoric acid is 30 to 50 parts.

6. The nickel-containing polishing composition according to claim 1, wherein the aluminum phosphate is present in an amount of 6 to 10 parts by weight.

7. The nickel-containing polish of claim 1 wherein said nickel nitrate is present in an amount of 1 to 2 parts by weight.

8. An aluminum piece polishing treatment method comprises the following steps: formulating a nickel containing polish according to any one of claims 1 to 7; and (3) immersing the aluminum piece into a polishing agent solution, carrying out treatment at preset time and temperature, washing the aluminum piece with water, and entering the next procedure.

9. An aluminum member polishing treatment method as set forth in claim 1, wherein after polishing for a predetermined time of 0.5 to 3 minutes at a predetermined temperature of 60 to 100 ℃, passivating again and then washing with water and drying.

10. An aluminum member characterized in that the surface of the aluminum member is polished by the aluminum member polishing treatment method as set forth in claim 8.