A high-corrosion-resistant single-coated zinc-aluminum-magnesium rare earth protective coating and its preparation process

Abstract

The invention discloses a highly corrosion-resistant single-coated zinc-aluminum-magnesium rare-earth protective coating and a preparation process thereof. The single-coated zinc-aluminum-magnesium rare-earth protective coating process of the present invention can utilize a single hot dipping method to obtain zinc and aluminum on the metal surface Magnesium alloy coating. The coating and the metal substrate each maintain their original performance, but have more than 99.9% of the metallurgical bonding interface. At the same time, the coating has a dense structure, stable composition, no missing plating, excellent corrosion resistance, and salt spray corrosion up to 2060h. The corrosion resistance of the alloy coating is better than that of ordinary hot-dip pure zinc coating, which improves the service life. The single-plating process can be reused and industrialized, and it overcomes the difficulties of metal and zinc-aluminum-magnesium alloy liquid electroplating. It is difficult to form an excellent bonding interface between the two, and it is easy to produce missing plating. It can be widely used in the preparation of metal surfaces. 5%-12% Al, 1%-6% Mg content of zinc-aluminum-magnesium alloy plating solution, the prepared co-permeation layer forms Zn / Al / MgZn2 ternary eutectic and various types of binary eutectic, which is eutectic The main reason for the high corrosion resistance of the seepage layer.

Description

Technical field:

[0001] The invention relates to the technical field of steel material surface coating technology, in particular to a highly corrosion-resistant single-coated zinc-aluminum-magnesium rare earth protective coating and a preparation process. Background technique:

[0002] The galvanized protective layer of the traditional metal substrate is affected by the deterioration of the natural environment and the electromagnetic environment of the transmission line, and the corrosion rate is accelerating, which greatly shortens its service life. In heavy corrosion environments (such as coastal areas, acid rain areas, industrial pollution areas, etc.), It has to be replaced as a whole, which greatly increases the maintenance cost and reduces the safety of the power grid. Especially in the electromagnetic field environment such as strong electric field and lightning strike, the electromagnetic effect will aggravate the corrosion of the coating. The zinc-aluminum-magnesiu...

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