RU2563281C1 - Method of producing enamel composition for temperature-control coatings - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: method of producing an enamel composition for temperature-control coatings of the "solar reflector" class includes preparing an enamel composition on a ball mill in a cup with grinding bodies. Production is carried out on a planetary ball mill in a metal cup with an inner layer of YZrO₂ with grinding bodies made of ZrO₂.

EFFECT: uniform distribution of the pigment in the enamel composition and temperature-control coating, uniform curing and reduced chalking of the temperature-control coating; the enamel compositions have a working life of 6 months.

2 cl, 4 tbl, 4 ex

Description

The invention relates to the field of space materials science and optical technology, and in particular to the field of manufacturing enamel compositions based on silicate binder for thermal control coatings (TRP) of the classes “true absorber” (IP) and “solar reflector” (CO), used as a passive thermal control system .

The decisive characteristics of TRP are the coefficient of absorption of solar radiation α _s , for TRP “IP” α _s → 1, for TRP CO α _s → 0, and the coefficient of thermal radiation (degree of blackness) ε, for TRP IP and CO ε → 1.

Thermoregulation coatings of the classes “solar reflector” (see RU 2421490 C1, C09D 1/02, C09D 5/24, C09D 5/33) and “true absorber” (see RU 2216557 C1 C09D 1/02, С04В are known from the patent literature 28/26), which include a silicate binder in the form of an aqueous solution. These patents describe a method for preparing compositions in porcelain ball mills with porcelain balls. The disadvantage of this method is the duration of the manufacture of enamel compositions, comprising from 4 to 10 hours.

The objective of the claimed invention is to reduce the manufacturing time of enamel compositions by 3-4 times.

EFFECT: uniform distribution of pigment in the enamel composition and thermostatic coating is achieved, uniform curing and reduction of chalking of the TRP are provided.

This object is achieved in that in a method for producing an enamel composition for thermoregulating coatings of the "solar reflector" class, comprising the manufacture of an enamel composition in a ball mill in a glass with grinding balls, the manufacture is carried out on a planetary ball mill in a metal glass with an inner layer of YZrO ₂ with grinding balls of ZrO ₂ in the following sequence of loading components:

1) dry milling in a glass with grinding balls of the calculated amount of BaAl ₂ O ₄ ;

2) adding 1/3 of the total amount of injected aqueous solution of lithium silicate and distilled water, dispersing BaAl ₂ O ₄ ;

3) the addition of 2/3 of the total amount of an aqueous solution of lithium silicic acid, the calculated amount of BaSO ₄ , dispersion to a milling degree of 35-40 microns.

A method of obtaining an enamel composition for thermoregulating coatings of the "true absorber" class, comprising manufacturing on a ball mill in a glass with grinding balls, the production being carried out on a planetary ball mill in a metal glass with an inner layer of YZrO ₂ with grinding balls of ZrO ₂ in the following sequence component downloads:

1) dry milling in a glass with grinding balls of the estimated amount of magnetite Fe ₃ O ₄ ;

2) adding distilled water, dispersing magnetite;

3) adding a calculated amount of BaAl ₂ O ₄ , dispersion;

4) adding the calculated amount of Co ₃ O ₄ , carbon black UM-76 and 1/3 of the total amount of the injected aqueous solution of lithium silicate, dispersion;

5) adding 2/3 of the total amount of an aqueous solution of lithium silicic acid, dispersing to a milling degree of 35-40 microns.

Example 1

The manufacture of an enamel composition for a temperature-controlled coating of the "solar reflector" class is carried out in a porcelain ball mill with porcelain balls according to the following recipe:

Aqueous solution of liquid lithium glass 29.42-33.78 (lithium silicate) Baso ₄ 42.28-43.44 BaAl ₂ O ₄ 3.39-3.61 Distilled water 22.07-23.53

The components are loaded into a porcelain glass:

Aqueous solution of liquid lithium glass 33.78 (lithium silicate) Baso ₄ 42.28 BaAl ₂ O ₄ 3.39 Distilled water 22.07

Dispersion time to a milling degree of 35-40 microns is 7 hours.

Example 2

The manufacture of enamel composition for thermal control coating of the class of "solar reflector" according to the recipe of example 1 in a planetary ball mill

Dispersion of the composition is carried out in a metal cup with an inner layer of YZrO ₂ ; balls with a diameter of 10 mm from ZrO ₂ are used as grinding bodies.

The method consists of the following stages, the modes are shown in table 1:

1. The estimated amount of BaAl ₂ O _{4 is} loaded into a glass with grinding balls.

2. The introduction of 1/3 of the total amount of injected aqueous solution of lithium silicate and distilled water.

3. The introduction of 2/3 of the total amount of an aqueous solution of lithium silicic acid and the estimated amount of BaSO ₄ .

The total production time of the enamel composition to a milling degree of 35-40 microns is 40 minutes

Example 3

The manufacture of an enamel composition for a thermoregulatory coating of the “true absorber” class is carried out in a porcelain ball mill with porcelain balls, according to the following recipe (mass parts):

Inorganic Silicate Binder - 1.00 lithium silicate Fe ₃ O ₄ (magnetite) 2.90-4.00 Co ₃ O ₄ 2.00-3.50 BaAl ₂ O ₄ 0.10-0.80 Soot UM-76 0.01-0.03 Distilled water 3,50-5,00

The components are loaded into the porcelain drum:

Inorganic Silicate Binder - 1.00 lithium silicate Fe ₃ O ₄ (magnetite) 2.90 Co ₃ O ₄ 2.00 BaAl ₂ O ₄ 0.10 Soot UM-76 0.02 Distilled water 3,50

Dispersion time to a milling degree of 35-40 microns is 4-6 hours.

Example 4

The manufacture of the enamel composition for thermal control coating class "true absorber" according to the recipe of example 3 in a planetary ball mill

Dispersion of the composition is carried out in a metal cup with an inner layer of YZrO ₂ ; balls with a diameter of 10 mm from ZrO ₂ are used as grinding bodies.

The method consists of the following stages, the modes are shown in table 2:

1. Preparing a slip. A calculated amount of Fe ₃ O ₄ (magnetite) is loaded into a glass with grinding balls.

2. The introduction of distilled water.

3. Introduction of the estimated amount of BaAl ₂ O ₄ .

4. The introduction of the estimated amount of Co ₃ O ₄ , carbon black UM-76 and 1/3 of the total amount of the injected aqueous solution of lithium silicate.

5. Introduction 2/3 of the total amount of an aqueous solution of lithium silicic acid.

The total production time of the enamel composition to a milling degree of 35-40 microns is 90 minutes

Thus, the proposed method for producing an enamel composition for temperature-controlled coatings:

- reduces manufacturing time by 3-4 times;

- improves the distribution of pigment in the enamel composition and coating;

- provides uniform curing of coatings;

- reduces chalking coatings.

The enamel composition was applied onto substrates of aluminum alloy AMg6 by the method of pneumatic spraying, the obtained characteristics of the temperature-controlled coating are shown in table 4.

Claims (2)

1. A method of producing an enamel composition for temperature-controlled coatings of the "solar reflector" class, comprising making an enamel composition on a ball mill in a glass with grinding balls, characterized in that the manufacture is carried out on a planetary ball mill in a metal glass with an inner layer of YZrO ₂ with grinding balls from ZrO ₂ in the following sequence of loading components:
1) dry milling in a glass with grinding balls of the calculated amount of BaAl ₂ O ₄ ;
2) adding 1/3 of the total amount of injected aqueous solution of lithium silicate and distilled water, dispersing BaAl ₂ O ₄ ;
3) adding 2/3 of the total amount of an aqueous solution of lithium silicic acid, the calculated amount of BaSO ₄ , dispersing to the desired degree of grinding. 2. A method of obtaining an enamel composition for thermal control coatings of the “true absorber” class, comprising manufacturing on a ball mill in a glass with grinding balls, characterized in that the manufacturing is carried out on a planetary ball mill in a metal glass with an inner layer of YZrO ₂ with grinding balls of ZrO ₂ with the following component loading sequence:
1) dry milling in a glass with grinding balls of the estimated amount of magnetite Fe ₃ O ₄ ;
2) adding distilled water, dispersing magnetite;
3) adding a calculated amount of BaAl ₂ O ₄ , dispersion;
4) adding the calculated amount of Co ₃ O ₄ , carbon black UM-76 and 1/3 of the total amount of the injected aqueous solution of lithium silicate, dispersion;
5) adding 2/3 of the total amount of an aqueous solution of lithium silicic acid, dispersing to the desired degree of milling.