Powder spraying process

Abstract

The invention discloses a powder spraying process which comprises the following steps: S1, spraying bottom powder on the surface of a workpiece to obtain a bottom powder coating; s2, spraying surface powder on the surface of the bottom powder coating in the S1; and s3, baking the surface of the workpiece obtained through spraying in the S2, and solidifying the base powder and the surface powder; the base powder mainly comprises epoxy resin, polyurethane resin, a sand texture agent and an auxiliary agent; the surface powder mainly comprises polyurethane resin, a sand streak agent and an auxiliary agent; and the percentage content of the sand streak agent in the bottom powder in the total mass of the bottom powder is smaller than the percentage content of the sand streak agent in the surface powder in the total mass of the surface powder. The base powder and the surface powder both contain the sand streak agent, the sand streak agent in the surface powder accounts for a large percentage content of the total mass of the surface powder, the surface powder coating is firstly heated and cured, convex and concave sand streaks are formed on the interface of the surface powder and the base powder, and the interface area of the base powder and the surface powder is larger than the coating area, so that the adhesive force between the base powder coating and the surface powder coating is increased; and the adhesion between the coatings is tighter, and meanwhile, the orange peel phenomenon is reduced.

Description

technical field

[0001] The invention relates to the technical field of painting, in particular to a powder spraying process. Background technique

[0002] In the manufacture of sheet metal products, spraying technology is one of the main key process technologies of sheet metal manufacturing. At the same time, the quality of product coating is an important indicator for evaluating the quality of sheet metal. It must not only achieve good anti-corrosion performance, but also require superior outdoor durability. performance.

[0003] At present, the conventional coating process adopts the method of two coats and two bakes. The two coats and two bakes process can improve the corrosion resistance of the coating, but the energy consumption is large, and the operation is complicated and affects the production efficiency. It is now replaced by the two-coating and one-baking process to improve the production efficiency of coating, but there are still the following defects: the pass ...