Oxidation-resistant graphite electrode surface coating and preparation process thereof

Abstract

The invention discloses an oxidation-resistant graphite electrode surface coating and a preparation process thereof. The oxidation-resistant coating comprises the following raw materials in parts by mass: 45 to 55 parts of SiC, 32 to 38 parts of AL2O3, 25 to 36 parts of ZrO2, 25 to 30 parts of solvent methanol, 30 to 35 parts of solvent ethanol, 2 to 5 parts of dispersant stearic acid and 12 to 18parts of a binding agent acrylic acid resin. The oxidation-resistant coating is prepared by the following steps: pulverizing the raw materials, sieving, preparing transition layer coating, preparingsealing layer coating, performing graphite electrode surface pretreatment, performing graphite electrode surface coating, performing vacuum sintering and performing scanning electron microscope representation. The oxidation-resistant coating of silicon carbide-aluminum oxide-zirconium oxide (SiC-AL2O3-ZrO2) is a composite coating, wherein the SiC belongs to a transition layer and is used for solving the conflict that the thermal expansion coefficient between a graphite composite material and the coating is not matched; and the AL2O3 and the ZrO2 serve as a barrier layer to provide a barrier for diffusion of oxygen, so that oxidation of the graphite electrode is avoided.

Description

technical field

[0001] The invention relates to graphite electrode surface treatment technology, in particular to an oxidation-resistant graphite electrode surface coating and a preparation process thereof. Background technique

[0002] Graphite electrode refers to petroleum coke, pitch coke as aggregate, coal tar pitch as binder, a kind of resistant electrode made by calcination of raw materials, crushing and grinding, batching, kneading, molding, roasting, impregnation, graphitization and mechanical processing. High-temperature graphite conductive materials are called artificial graphite electrodes (referred to as graphite electrodes) to distinguish them from natural graphite electrodes prepared from natural graphite.

[0003] Graphite material begins to oxidize from about 400°C, and the oxidation increases sharply after exceeding 750°C, and the oxidation also intensifies as the temperature increases. Oxidation corrosion under such high temperature conditions will lead to...