The counterpoint relationship of zinc alloy brands, such as No.2, No.3, No.4 and No.5, corresponds to that standard brand.

C20D steel corresponding to No.2, No.3, No.4 and No.5 is close to domestic 20# steel, which belongs to high-quality low-carbon steel and has been cold-extruded, carburized and hardened. The steel has low strength and good toughness, plasticity and weldability. The tensile strength is 253-500MPa, and the elongation is ≥24%.

Large and medium-sized machinery manufacturing, such as forging or pressing tie rods, shackles, levers, sleeves, fixtures, etc. Tubes, flanges, headers and various fasteners commonly used in non-corrosive media with pressure ≤6N/ m2 and temperature ≤450℃ in steam turbine and boiler manufacturing industries; Used for manufacturing crossheads, pistons and other castings of railways and rolling stock.

Extended data:

Zinc-based alloy is an alloy composed of zinc and other elements. Commonly added alloying elements are aluminum, copper, magnesium, cadmium, lead, titanium and so on. Zinc-based alloys have good formability, low melting point and good fluidity. When melting and die casting, it does not absorb iron, corrode and form, and does not stick to the mold. Precision parts with complex shape and thin wall can be die-cast, and the casting surface is smooth. Fusion welding and brazing; It has good mechanical properties and wear resistance at room temperature and corrosion resistance in the atmosphere.

Waste materials are easy to recover and re-melt; Surface treatment can be carried out, such as electroplating, spraying and painting. However, its creep strength is low and it is easy to change its size due to natural aging. Compared with babbitt alloy, it not only has obvious cost performance advantages, but also has higher strength and toughness, lower specific gravity and wider application range. Widely used in automobiles, machinery manufacturing, printed circuit boards, battery cathodes, etc.

There are two smelting processes for zinc-based alloys: direct smelting and master alloy smelting. Direct smelting method is a method that zinc, copper and aluminum are poured into a crucible according to their composition ratio for direct smelting. Master alloy smelting method is to melt copper and aluminum into master alloy, and then prepare zinc alloy from master alloy.

This method can reduce the oxidation and burning loss of alloy elements and the overheating of molten metal, facilitate the control of alloy chemical composition, save energy and shorten the smelting period.

Baidu encyclopedia-zinc-based alloy