SU1723195A1 - Method for protection against corrosion - Google Patents

Abstract

The invention relates to the chemical treatment of metals, in particular, to methods of protecting the surface from corrosion before painting by electrodeposition, and can be used in various devices of instrument and mechanical engineering. Stabilizing the corrosion resistance of the phosphate coating during storage, reducing its solubility during electroplating, increasing the corrosion resistance, abrasion resistance and adhesion of the paint coating are achieved by treating in a solution containing, g / l: salt Mazhef 30-40, zinc nitrate 50-70, sodium fluoride 0.005-0.007; sodium carbonate 0.08-0.1; as a surfactant, sodium, potassium, manganese or zinc (0.08-0.1) Su-Syfluoroalkanesulphonate at a temperature of 55-65 ° C for 5-8 minutes by washing in sodium, potassium perfluoroalkanesulfonate solution , manganese or zinc with a concentration of 0.15-0.2 g / l at 40-50 ° C. 1 tab. -5 y

Description

The invention relates to the chemical treatment of metals, in particular, to the protection against corrosion of the surface prior to electroplating, and can be used in various fields of instrumentation and mechanical engineering.

The purpose of the invention is to stabilize the corrosion resistance of the phosphate coating during storage, reduce its solubility during electrodeposition, increase the corrosion resistance, resistance to abrasion and adhesion of the paintwork.

The goal is achieved by those. that the surface treatment of the metals is carried out at 55-65 ° C for 5-8 minutes in solution. Containing salt Mazhef, zinc nitrate, sodium fluoride, sodium carbonate and perfluoroalkanesulfonate sodium, potassium, manganese or zinc at

the following ratio is component-; com, g / l ;.

Salt Mazeff30-40

Zinc nitrate 50-70

Sodium fluoride0,005-0.007

Sodium carbonate 0.08-0.1

St-Syu perfluoroalkane-sodium, potassium, manganese sulfonate

or zinc 0.08-0.1,

After that, St-Xu solution was washed with sodium, potassium, manganese or zinc perfluoroalkanesulfonate (PFAS) with a concentration of 0.15-0.2 g / l at 40-50 ° C at a voltage of 100 V for 2 minutes. The coating was dried at 180 ° C for 1 hour.

Quality assessment of phosphate and paint coatings (LCP) was carried out according to the following indicators (see table):

Vj

Yu OJ

YU

cl

determination of the corrosion resistance of the phosphate coating - by the Akimov method (GOST 9.302-79, p. 33, solution number 46); determining the corrosion resistance of paintwork products according to GOST 9.403-80, method 1 - by immersing the sample in a 3% solution of sodium chloride until the appearance of the first center of corrosion;

determination of abrasion resistance of paintwork materials - according to GOST 20811-75. Method A:

determination of adhesion LKP - by the method of radiation incisions;

determination of the relative solubility of phosphate layers - by calculating the mass loss ratio of the phosphate layer during electrodeposition to the total mass of phosphate coating before electrodeposition. LCP was removed in acetone.

The technical and economic efficiency of the proposed method is to increase the period of interoperable storage of phosphated (parts, corrosion resistance, abrasion resistance and adhesion of paint coatings, which in turn leads to an increase in the shelf life of products with LPCs and improve their performance.

Claims (1)

Claim Method A method for protecting against corrosion, including the preparation of the surface of metals under electrodeposition by treatment in a solution containing a Mazef salt, zinc nitrate and surfactant, washing and drying, characterized in that, in order to stabilize the corrosion resistance of the phosphate coating during storage, reduce its solubility during electrodeposition, increase the corrosion durability, resistance to abrasion and adhesion of the paint-and-lacquer coating, treatment is carried out from a solution, additionally containing sodium fluoride, sodium carbonate, as a surfactant containing o St-Syu-perfluoroalkanesulphonate sodium, potassium, manganese or zinc in the following ratio of components, g / l: Salt Mazeff30-40 Zinc nitrate 50-70 Sodium fluoride0,005-0,007 Sodium carbonate0,008-0,1 St-Syu-perfluoroalkane-sulfonate of sodium, potassium, manganese or zinc 0.08-0.1, at a temperature of 55-65 ° C for 5-8 minutes, and the washing is carried out in a solution of St-Syu-perfluoroalkanesulfonate sodium, potassium, manganese or zinc with a concentration of 0.15-0.2 g / l at 40-50 ° C . to to Salt Iazhef35 2n (HO,) j60407 NaF0,006 №1.00, 0.09 Cf-IWtC sodium + pro-0.09 ia ka rastaore C, -PPAS sodium 0,1740I Sol Ma at 35 gp (KO, b60608 K.F0.006 KP, CO, 0.09 SL-PFAS sodium + pro-0.09. Manica solution0.09 Sv-P "AC Sodium 0,17W 1 Sol N "mf35 Zn (H04), 60608 KaF0.006 K, CO, 0.09  sodium + pro-0.09 sym solution "Anola0,1.40-.1 70 ... II S IS nineteen. 7s one M Extend table