Preparing method for electric-conduction and anti-corrosion cobalt and manganese spinel coating

Abstract

The invention provides a preparing method for an electric-conduction and anti-corrosion cobalt and manganese spinel coating. The preparing method includes the following steps that firstly, surface pretreatment is conducted on a ferrite stainless steel base body; secondly, a cobalt and manganese alloy-manganese hydroxide compound coating is prepared on the surface of the ferrite stainless steel base body on which surface pretreatment is conducted in the first step through a double-electrode electrochemical deposition method; thirdly, first thermal transition treatment is conducted, and the cobalt and manganese alloy-manganese hydroxide compound coating is obtained; and fourthly, second thermal transition treatment is conducted, and the electric-conduction and anti-corrosion cobalt and manganese spinel coating is obtained. The preparing method is simple in technology and low in equipment requirement and cost, the adhesion force between the prepared coating and the base body is good, density is high, the coating comprises an Mn1.5Co1.5O4 spinel layer highest in electric conductivity in a cobalt and manganese spinel system, and harsh working conditions of the surface of a solid oxide fuel cell metal connector can be better met.

Description

Technical field [0001] The invention belongs to the technical field of surface coating material preparation, and specifically relates to a preparation method of a conductive and corrosion-resistant cobalt-manganese spinel coating. Background technique [0002] The solid oxide fuel cell is an all-solid chemical power generation device that directly converts the chemical energy of the reactants into electrical energy under medium and high temperature conditions. It is the fourth generation of energy after thermal power, hydropower, and nuclear power-the fuel cell family- One of its members, with its high energy conversion rate and environmental friendliness, is known as the green energy of the 21st century and has broad application prospects. The solid oxide fuel cell is a high-temperature fuel cell with high operating temperature, high requirements for materials, and problems such as thermal expansion. Therefore, the cost remains high, which hinders its popularization and applicat...

AI Technical Summary

Problems solved by technology

However, ferritic stainless steel faces the following problems in the service environment of solid oxide fuel cells: (1) insufficient high temperature corrosion resistance, (2) surface corrosion product film leads to increased contact resistance, (3) surface Cr 2 o 3 Film Formation Volatile Cr-Containing Media Causes Cathode Poisoning

However, the preparation of cobalt-manganese spinel coating by electrodeposition of cobalt-manganese alloy has low manganese content, and Mn with high manganese content and higher conductivity cannot be obtained. 1.5 co 1.5 o 4 Coating system, even if the manganese content is increased through process improvement, the coating is thin and cannot improve the oxidation resistance of the ferritic stainless steel substrate for a long time

Up to now, no reports have been found on the preparation of conductive and corrosion-resistant cobalt-manganese spinel coatings with high manganese content by electrodeposition of cobalt-manganese metal + manganese hydroxide coating-manganese hydroxide conversion heat treatment-high temperature thermal conversion method

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