RU2525705C1 - Method of making arrays for workpieces of elements of light-reflecting systems - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: method includes preliminary chemical and mechanical treatment of a surface, depositing an intermediate zinc layer by chemical deposition from a multi-component zinc-containing solution followed by removal of said layer, re-depositing the zinc layer using a similar technique and depositing, by chemical reduction, a target nickel-phosphorus layer from a solution of a mixture of multi-component nickel and phosphorus compounds. A process additive of amino acetic acid is further added in amount of 10-15 g/l to the solution. The process of obtaining the desired coating is carried out in a single cycle at temperature of 80-90°C. After depositing the nickel-phosphorus layer, heat treatment is carried out at temperature not higher than 400°C.

EFFECT: high adhesion and strength of the coating.

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Description

The present invention relates to the field of manufacturing technology of matrices of complex shape for blanks of elements of retroreflective systems, and can be used to protect parts of a spherical or conical shape from the effects of high dynamic loads during tool processing.

A known method of manufacturing matrices for parts of complex profile (RF patent No. 02445181, IPC B21D 22/16, publ. 03/20/12,), including pre-fabrication of the matrix, with a profile of a given shape to obtain a hollow product, compression of the blank of the hollow part, subsequent processing and freeing the finished part (cue) from the matrix.

The disadvantages of the analogue include the difficulty of manufacturing parts with a high degree of accuracy of the matrix profile reproduced in the replica and the observance of the requirements for the purity of surface treatment and minimizing the mass of finished products.

Closest to the claimed is a method of manufacturing a lighting device (RF patent No. 02225061, IPC H01S 3/09, publ. 02.27.04), including preliminary chemical-mechanical surface treatment of complex parts, applying a metallized sublayer and applying a target nickel-containing coating, removal target layer in the form of a foil (replica), installing it in the device.

The disadvantages of the prototype include the difficulty of manufacturing parts with a high degree of accuracy of the reproduced profile and compliance with the requirements for clean surface treatment and limiting the mass of finished products.

The task of the authors of the present invention is to develop a method of manufacturing matrices for blanks of elements of reflective systems, allowing to form a complex profile of optical mirrors, functional elements of searchlights and other details.

A new technical result provided by using the proposed method is to provide high adhesion and durability of the coating on composite aluminum alloy matrices for the manufacture of parts of optical reflective systems representing bodies of revolution intended for subsequent high-intensity tool processing.

These tasks and a new technical result are ensured by the fact that, in contrast to the known method of manufacturing matrices for blanks of elements of retroreflective systems, including preliminary chemical-mechanical surface treatment of complex parts corresponding to the profile of the finished product, applying a metallized sublayer and applying a target nickel-containing coating, according to the proposed method first, an intermediate zinc film is deposited by chemical deposition from a multi-component zinc code the rusting solution, followed by removal of this layer to activate the surface of the coated parts, re-applying the zinc film by the same method, after which the target nickel-phosphorus layer with a thickness of up to 200 μm is applied by chemical empirical formula Ni _n P _m , where n, m are the indices, corresponding to the stoichiometric ratio of these elements in the starting compounds, from a solution of a mixture of multicomponent compounds of nickel and phosphorus with a volume to surface ratio of 4: 1, to the composition of this solution up to Aminoacetic acid technological additive is added in an amount of 10-15 g / l, and the process of obtaining the target coating is carried out in one go at a temperature of 80-90 ° C, after which they heat-treat complex parts in the temperature range up to 400 ° C, turning and polishing to 6-8 Å.

The proposed method is illustrated as follows.

Initially prepare the surface of the workpiece for complex parts by traditional methods of chemical-mechanical processing, degreasing, etching. The etching process is carried out in a solution of the composition (g / l): nitric acid, hydrofluoric acid; water in a ratio of 1: 1: 10, respectively.

Then, an intermediate layer in the form of a zinc film is applied to the prepared surface of the workpiece for complex parts by chemical deposition from a multicomponent zinc-containing solution, followed by removal of this layer, which is necessary to activate the surface of the coated parts. Next, re-applying the zinc film by a similar method.

After that, by chemical reduction, the target nickel-phosphorus layer up to a thickness of 200 μm is applied with the empirical formula Ni _n P _m from a solution of a mixture of multicomponent compounds of nickel and phosphorus with a volume to surface ratio of 4: 1. In the composition of this solution, a technological additive of aminoacetic acid in an amount of 10-15 g / l was additionally introduced.

The process of obtaining the target coating is carried out in one go at a temperature of 80-90 ° C, after which they heat-treat complex parts in the temperature range up to 400 ° C, turning and polishing up to 6-8 Å.

When carrying out all the operations of the proposed method, a high degree of adhesion and coating strength is achieved for composite aluminum alloy products, which are rotation bodies intended for subsequent high-intensity instrumental surface treatment to impart a high degree of purity to a mirror finish. Achieving a high degree of processing purity is an essential requirement for this type of optical systems (mirrors).

As shown by experimental studies, when using the proposed method provides a higher degree of adhesion and coating strength on complex aluminum alloy products, which are bodies of revolution, than this could be achieved in the prototype.

The possibility of industrial application of the proposed method is confirmed by the following examples of specific implementation.

Example 1. The proposed method was implemented in laboratory conditions on cylindrical hollow billets of aluminum alloy AmG6 and consisted of the following operations:

- degreasing with a detergent;

- washing in hot water;

- washing in cold water;

- etching in a solution of the composition, (g / l):

nitric acid 1 part hydrofluoric acid 1 part water 10 pieces

room temperature 15-35 ° C, etching time 3 minutes;

- washing in cold water;

- application of I zincate film from a solution of the composition, (g / l):

zinc oxide 100-120 sodium hydroxide 400-500 potassium sodium tartrate 10-20 sodium nitrate one ferric chloride 1-2

room temperature 15-35 ° C, application time 1 minute;

- washing in cold water;

- removal of zincate film in a solution of the composition, (g / l):

Nitric acid 350-400 hydrofluoric acid 15-20

room temperature 15-35 ° C, removal time 30 seconds;

- washing in cold water;

- application of II zincate film similarly to I zincate film;

- washing in cold water;

- chemical nickel plating in a solution of the composition, (g / l):

nickel sulfate 25-30 sodium hypophosphite 20-25 sodium acetate 0-15 thiourea 0.003 aminoacetic acid 12-15

temperature 80-90 ° C, pH 4.5;

- washing in cold water;

- drying;

- gravimetric method for controlling the thickness of the nickel coating layer;

- heat treatment of 300 ° C for 1 hour.

Example 2. The proposed method in the conditions of example 1 was tested on billets of alloy AmG6 with similar operations, with subsequent heat treatment at 110 ° C for 6 hours and at 400 ° C for 0.5 hours.

Implemented examples have confirmed the achievement of the claimed technical result, which consists in ensuring a high degree of adhesion and coating strength on complex aluminum alloy products, which are bodies of revolution. The following surface cleanliness indicators were achieved (which is critical for reflective elements of optical systems): the average roughness (Ra) of the mirror is 4 Å; mean square deviation of the profile (rms) 6 Å; the average Ra value over all measured points (such control points - 17) of the mirror is 6 Å; the root mean square deviation of the profile (rms) is 8 Å (see FIG. 1).

Claims (1)

A method of manufacturing matrices for blanks of elements of retroreflective systems, including preliminary chemical-mechanical surface treatment of complex sections corresponding to the profile of the finished product, applying a metallized sublayer and applying the target nickel-containing coating, characterized in that the intermediate zinc film is first deposited on the surface of the workpiece by chemical deposition from a multi-component zinc-containing solution, followed by removal of this layer to activate the surface and coated parts, then re-applying the zinc film by a similar method, after which, by chemical reduction, the target nickel-phosphorus layer up to 200 μm thick is applied with the empirical formula Ni _n P _m , where n and m are indices depending on the stoichiometric ratio of the starting compounds of these elements , from a solution of a mixture of multicomponent compounds of nickel and phosphorus with a volume to surface ratio of 4: 1, a technological additive of aminoacetic acid in an amount of 10-15 g / l, and the process of obtaining the target coating is carried out in one step at a temperature of 80-90 ° C, after which they heat-treat complex parts in the temperature range up to 400 ° C, turning and polishing up to 6-8 Å.