Novel air-fuel gas type supersonic flame spray gun, spraying device and method for preparing metal ceramic coating

Abstract

The invention discloses a novel air-fuel gas type supersonic flame spray gun, a spraying device and a method for preparing a metal ceramic coating. The novel air-fuel gas type supersonic flame spray gun comprises a combustion chamber, a gun barrel and a coaxial tailstock, wherein the gun barrel and the coaxial tailstock are coaxially arranged at the front end and the rear end of the combustion chamber; a combustion chamber shell is arranged outside the combustion chamber and the coaxial tailstock; a gun barrel shell is arranged outside the gun barrel and communicates with the combustion chamber shell; a high-pressure air inlet and an ignition needle are arranged on the combustion chamber shell; high-pressure air distribution holes are distributed in the coaxial tailstock; cooling air outlets are distributed in the gun barrel shell; and a catalytic copper plate is arranged between the coaxial tailstock and the combustion chamber. According to the novel air-fuel gas type supersonic flamespray gun, the flame temperature is greatly reduced, the particle speed is greatly increased, the flame temperature at an outlet of the spray gun is lower than 1600 DEG C, the particle speed reaches1200 m / s, and preparation of a high-performance amorphous coating is achieved. The WC-10Co4Cr metal ceramic coating obtained through the method for preparing the metal ceramic coating has the advantages that the coating can be effectively prevented from being peeled off, and the corrosion resistance is good.

Description

technical field [0001] The invention belongs to the technical field of supersonic flame spraying, and in particular relates to a novel air gas type supersonic flame spraying gun, a spraying device and a method for preparing a cermet coating. Background technique [0002] The traditional gas-oxygen supersonic thermal spraying technology provides powder heating and acceleration energy through gas and oxygen combustion. The flame temperature at the spray gun outlet is above 2800°C, and the powder particle velocity is 700-900m / s. There is a high heating temperature, and the powder particles are in the flame. Shortcomings such as long residence time in the flow will lead to serious oxidation of powder particles and reduce coating performance, and low particle velocity will also cause shortcomings such as coating density and low bonding strength. For powders such as amorphous, this technology cannot retain the amorphous state of the coating because the flame temperature is too hig...

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