RU2256010C1 - Aqueous electrolyte for depositing iron-manganese alloy - Google Patents

Abstract

FIELD: electroplating, possibly deposition of coatings with enhanced wear resistance and rigidity in machine engineering.

SUBSTANCE: aqueous electrolyte contains, g/l: iron chloride, 350 - 450; manganese chloride, 35 - 45; aluminum chloride, 30 - 50; Trilon , 5 - 15; potassium iodide, 20 - 30; iodine, 10 - 20.

EFFECT: enhanced rigidity, corrosion proofness, wear resistance and cohesion of coating with steel base.

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Description

The invention relates to the field of electroplating, in particular to electrolytic deposition of an alloy of iron-manganese.

Known electrolyte for the deposition of the iron-manganese alloy containing iron, manganese and aluminum chlorides [Povetkin V.V., Zhikharev A.I., Zhikhareva I.G., Zakharov M.S. // Electrochemistry. - 1974. - T. 10. - No. 3. - S.446-448]. From the indicated electrolyte, coatings are formed with low hardness (380-460 MPa) and low wear resistance (0.0038-0.0042 kg / m ² · h) and corrosion resistance (0.22-0.26 kg / m ² · h) . Corrosion resistance was determined in a 0.1 N sulfuric acid solution for 58 hours, and the wear rate under dry friction on a counterbody made of cast iron after 20 hours of testing.

The task to be solved by the claimed invention is directed, is the preparation of an aqueous electrolyte, which allows the deposition of hard, resistant to wear and corrosion coatings with an alloy of iron-manganese, designed to restore worn parts of machines.

The problem is solved by achieving a technical result, which consists in improving the properties and quality of coatings.

The specified technical result is achieved by the fact that in the known aqueous electrolyte for precipitation of the iron-manganese alloy containing iron chloride, manganese chloride and aluminum chloride, the feature is that it additionally contains the complexing agent trilon B (disodium salt of ethylenediaminetetraacetic acid), potassium iodide and iodine in the following ratio of components, g / l: iron chloride - 350-450, manganese chloride - 35-45, aluminum chloride - 30-50, potassium iodide - 20-30, Trilon B - 5-15, iodine - 10-20.

An additional introduction of Trilon B binds the ferric ions formed during electrolysis into very strong trilonate complexes (logβ _Fe ^{+ 2} / _EDTA = 25.1), which reduces the oxidizability of solutions and improves the stability of the electrolyte.

Potassium iodide in the electrolyte increases the conductivity and inhibits the deposition of the alloy, thereby contributing to an increase in the applied current densities.

The introduction of iodine into the electrolyte grinds the structure of the resulting precipitation, increases the hardness, wear resistance of the coatings and their adhesion to the base.

An aqueous electrolyte is prepared by dissolving iron chloride, manganese chloride and Trilon B in separate portions of distilled water. One part of Trilon B solution is added with stirring to the iron chloride solution, and the other to the manganese chloride solution. Mixtures of the solutions are left for 10-15 minutes until complete complexation, and then, with continuous stirring, a solution of manganese complexonate is added to the solution of iron complexonate. Solutions of aluminum chloride, potassium iodide and iodine are successively added to the resulting mixture.

The deposition process is carried out at an electrolyte pH of 0.5-1.5, a cathode current density of 10.0-30.0 A / dm ² and a temperature of 30-40 ° C with continuous stirring using iron anodes.

Specific examples of the use of electrolyte and some properties of the coatings are given in the table.

The hardness and corrosion resistance of the resulting coatings from the proposed electrolyte increases by 15-20% and 20-35%, respectively, compared with the precipitation of the iron-manganese alloy obtained from the known electrolyte. The wear resistance of alloy precipitates obtained from the proposed electrolyte is 1.5-2.0 times higher than the precipitated from the known.

The use of the proposed electrolyte allows the deposition of coatings firmly adhered to the steel substrate, which do not peel off from the substrate after heating at 250 ° C for 1 h and subsequent rapid cooling.

Table No. Electrolyte components, g / l and research results The composition of the examples 1 2 3 1. Iron chloride 350,0 400,0 450,0 2. Manganese Chloride 35.0 40,0 45.0 3. Aluminum chloride 30,0 40,0 50,0 4. Potassium iodide 20,0 25.0 30,0 5. Iodine 10.0 15.0 20,0 6. Trilon B 5,0 10.0 15.0 7. The current density, A / DM ² 10.0 20,0 30,0 8. Temperature ° C 30,0 35.0 40,0 9. pH 0.5 1,0 1.5 10. Precipitation of Manganese 0.6 1.4 2.1 eleven. Current output 84.0 91.0 96.0 12. Microhardness, kg / mm ² 690 700 705 thirteen. The corrosion rate, g / m ² · h 0.19 0.18 0.12 14. Wear rate, kg / m ² · h 0.0021 0.0023 0.0025 fifteen. Appearance of coatings bright light gray dark grey

Claims (1)

An aqueous electrolyte for the deposition of an iron-manganese alloy containing iron chloride, manganese chloride and aluminum chloride, characterized in that it further comprises a complexing agent Trilon B, potassium iodide and iodine in the following ratio of components, g / l: Ferric Chloride 350-450 Manganese Chloride 35-45 Aluminum chloride 30-50 Trilon B 5-15 Potassium iodide 20-30 Iodine 10-20