The difference between cold galvanized mesh and hot galvanized mesh

Galvanizing is a surface treatment technology, which refers to a zinc coating on the surface of metals, alloys or other materials for aesthetics and anti-rust effects. After the zinc coating is passivated, dyed or coated with light protection agent, its protective and decorative properties can be significantly improved.

The hot-dip zinc layer is formed by zinc in liquid state in three steps. The surface of the iron base is dissolved by the zinc liquid to form a zinc-iron alloy phase layer; the zinc ions in the alloy layer further diffuse to the substrate to form a zinc-iron mutual-soluble layer; the alloy layer coated with zinc.

Cold-dip galvanizing is also called electro-galvanizing. It uses electrolytic equipment to degrease and pickle the pipe fittings, then put them into a solution composed of zinc salt, and connect the negative electrode of the electrolytic equipment. When the positive pole of the equipment is powered on, a layer of zinc will be deposited on the pipe fittings by using the directional movement of the current from the positive pole to the negative pole. The cold-galvanized pipe fittings are processed first and then galvanized.

Hot-dip galvanizing: It is difficult to dissolve in water, so it plays a certain role in protecting the steel fastener substrate. If zinc oxide and other components in the atmosphere form insoluble zinc salts, the anti-corrosion effect is more ideal; it has a zinc-iron alloy layer, which is densely combined, and exhibits unique corrosion resistance in marine salt spray atmospheres and industrial atmospheres; due to the combination Strong, zinc-iron mutual solubility, strong wear resistance; due to the good ductility of zinc, its alloy layer is firmly attached to the steel substrate, so hot-dip galvanizing can be used for cold punching, rolling, drawing, bending, etc. The forming process does not damage the coating; after the steel structure is hot-dip galvanized, it is equivalent to an annealing treatment, which can effectively improve the mechanical properties of the steel substrate, eliminate the stress of the steel forming and welding, and facilitate the turning of the steel structure.

Cold galvanizing: the zinc coating is thicker, the crystallization is fine, uniform and non-porous, and the corrosion resistance is good; the zinc layer obtained by electroplating is relatively pure, and it corrodes slowly in the mist such as acid and alkali, so it can effectively protect and fasten the sand piece substrate. The zinc layer is passivated by chromic acid to form white, colorful, army green, etc., which are beautiful and elegant, and have a certain degree of decoration. Due to the good ductility of the galvanized layer, it can be used for cold stamping, rolling, bending, etc. Forming without damaging the plating.

Hot-dip galvanizing is suitable for strong corrosive environments such as various strong acids and alkali fog.

Cold galvanizing is widely used in machinery manufacturing, making galvanized chain link fence, electronics, precision instruments, chemical industry, transportation, aerospace, etc.