Metal surface treatment method

[Method 7]

In the lead-lined tank, the sulfuric acid concentration is 500g/l, anodized for 90s, the voltage is 6V, rinsed with water, washed with distilled water, dried at 70°C, and the glued parts are anodes. After treatment, it is treated in 5-10% chromium oxide solution Passivation for 20min.

[Method 8]

Immerse in the following solution at 85-90°C for 10 minutes:

Oxalic acid  37  Sulfuric acid (d=1.84)  36  Water  300

After washing with distilled water, dry with warm air.

[Method 9]

After degreasing, soak in the following solution at 65°C for 10 minutes:

Hydrochloric acid (d=1.19)  52  Hydrogen peroxide (30%)  2  Formaldehyde (38%)  10  水 45

After washing with water, immerse it in the following solution for 10 minutes at a temperature of 65°C:

Sulfuric acid (d=1.84) 100  Sodium dichromate  10  水  30

After washing with distilled water, dry at 70°C.

[Method 10]

After alkali washing with water-soluble industrial soap, washing with hot water at 40°C for 5 minutes, drying at 120°C, immersion in the following solution at 100°C for 2 minutes:

Hydrochloric acid 200  phosphoric acid 30   hydrofluoric acid  10

Wash with hot water at 40°C for 5 minutes and dry at 40°C for 30 minutes.

5. Surface treatment method of carbon steel and ferroalloy

[method 1]

Common solvents for degreasing: trichloroethylene, acetone, ethyl acetate, gasoline, benzene, absolute ethanol.

[Method 2]

Degreasing after sandblasting or sanding.

[Method 3]

Immerse in 10% water glass aqueous solution at 60°C for 10-15min, then wash with water and dry.

[Method 4]

Immerse in 18% hydrochloric acid aqueous solution at room temperature for 5-10min, rinse with cold water, rinse with distilled water, and dry at 93°C for 10min.

[Method 5]

Treat the mixture in an equal amount of concentrated phosphoric acid and formaldehyde at 60°C for 10 minutes, then wash with water and dry.

[Method 6]

After degreasing, immerse in 3.5% sodium hydroxide solution at 60°C for 20 minutes, rinse with cold water, then actinize in 5% nitric acid solution for 10 minutes, rinse with cold water, and then immerse in the following solution:

Sodium dichromate  7.5  sulfuric acid  24  水 77

After immersing for 20 minutes at 65°C, wash with hot water at 60°C, then wash with cold water, and dry at 70°C.

[Method 7]

Immerse in the following solution at 71-77°C for 10 minutes:

Sodium dichromate  4   sulfuric acid (d=1.84) 10  水  30

After washing with water and distilled water, dry at 93°C.

[Method 8]

Immerse in the following solution at 60-65°C for 5 minutes:

Sodium silicate   30     sodium alkyl aryl sulfonate   3     water  967

Wash with water, hot distilled water, and dry at 100-105°C.

[Method 9]

Immerse in the following solution at 60°C for 10 minutes:

Phosphoric acid (88%) 10  Ethanol 20

The carbon residue is washed away by running water, washed with distilled water, and dried at 120°C for 30 minutes.

Six, titanium and titanium alloy surface treatment methods

[method 1]

Common solvents for degreasing: trichloroethylene, acetone, methyl ethyl ketone, benzene, ethyl acetate, gasoline, absolute ethanol.

[Method 2]

After degreasing, soak in the following solution at 20°C for 5-10 minutes:

Sodium fluoride  2   chromium oxide  1  sulfuric acid (d=1.84) 10  水  50

Rinse with water, rinse with distilled water, and dry at 93°C.

[Method 3]

Treat in the following solution at 20°C for 2min:

Hydrofluoric acid (concentrated) 84  hydrochloric acid (37%) 8.9  phosphoric acid (85%)  4.3

Rinse with water, rinse with distilled water, and dry at 93°C.

[Method 4]

After degreasing, wash with alkaline aqueous solution, and then treat in the following solution at room temperature for 4-6 min:

Nitric acid (70%) 5  ammonium fluoride  3  水 92

After washing with water, treat in the following solution at room temperature for 2 minutes:

Trisodium phosphate   5   Sodium fluoride  1  Hydrofluoric acid  1.5   水 92.5

Dry after washing with water.

[Method 5]

After degreasing, scrub with the following solution for 2-3min:

Trisodium phosphate   5   Sodium fluoride 1.3  Hydrofluoric acid  2.9  Water  90.8

After washing with water, dry at 60°C.

Seven, zinc and zinc alloy surface treatment methods

[method 1]

Common solvents for degreasing: trichloroethylene, acetone, methyl ethyl ketone, ethyl acetate, gasoline.

[Method 2]

After degreasing, immerse in the following solution at room temperature for 2-4 minutes:

Hydrochloric acid (37%) 10-20  Water  90-80

Wash with warm water, distilled water, and dry at 66-71°C for 30 min.

[Method 3]

Immerse in the following solution at 38°C for 3-6min:

Sulfuric acid (d-1.84) 2  Sodium dichromate   1  Water  8

Rinse with cold water, rinse with distilled water, and dry at 40°C.