Zinc alloy die castings are widely used in furniture hardware decoration, bags, bathrooms, communications, digital and other industries. Why do many related enterprises choose zinc alloy die casting products as accessories? Compared with other casting methods, zinc alloy die casting has the following advantages: high dimensional accuracy, good stability; good surface finish, easy to electroplating, spraying and other surface treatment; complex shape of die casting products, thin wall; rapid cooling, shorten casting cycle; recyclable. Consistent with social propaganda. Environmental protection. According to statistics, about half of the world's zinc consumption is used for galvanizing, about 10% for brass and bronze, less than 10% for zinc-based alloys, and about 7.5% for chemicals. Zinc can be prevented from corrosion by hot dipping in molten metal tanks of materials and products that need protection.
First of all, we must understand the classification of die casting machine parts.
Die-casting machine accessories are generally divided into hot chamber die-casting machine and cold chamber die-casting machine. Cold chamber die-casting machine is divided into horizontal die-casting machine and vertical die-casting machine according to the structure and layout of the chamber.
Full vertical die casting machine) two kinds.
1. Die casting machine parts hot-press chamber die casting machine room immersed in liquid metal thermal insulation melting crucible, injection parts are not directly connected with the base, but installed on the crucible. The die casting machine has the advantages of simple production process, high efficiency, less metal consumption and stable process. However, in the cavity, the injection punch is immersed in liquid metal for a long time, which affects its service life. It is easy to increase the iron content in the alloy. Hot chamber die-casting machine is mainly used for zinc alloy and other low melting point alloy castings, but also for small-scale Al-Mg alloy die-casting.
2. The chamber of the cold chamber die-casting machine is separated from the holding furnace. In the process of die casting, liquid metal is removed from the holding furnace and poured into the die casting chamber.
Horizontal die casting process: 1 injection punch, 2 cavity, 3 liquid metal, 4 finalizing, 5 moving, 6 cavity, 7 door cavity, 8 residual cooling chamber die casting machine is mainly used for aluminum alloy die casting.
Polishing: Polishing enables parts to achieve mechanical smoothness and brightness. The whole cloth wheel should be used for polishing. When polishing with butter paste and white paste, attention should be paid to using less and less polishing paste.
Because polishing paste often makes polishing wax stick to concave surface of parts, it brings difficulties to degrease. When there is less polishing paste, it will cause local overheating and form compact spots on the surface of parts. Bubbles are easily produced after plating, especially after baking and plating. The author often mistakenly believes that the problem of matrix material is that the diameter and speed of polishing wheel should not be too high, and the maximum circumferential speed should not exceed 215. 0 m/min: Mining small or complex parts at a low speed of 1100-1600 m/min: The dense layer on the surface of the parts should not be destroyed to prevent and reduce the exposure of subsurface voids, so as to achieve polishing and luminescence.
For metal products, batch galvanizing can be used; for rolled steel strip coil, continuous galvanizing can be used. In recent years, hot-dip galvanizing of flat steel has been greatly improved. In today's market, zinc alloy die casting enterprises are often surprised by the rapid changes in their market conditions. The initial sales of good products are getting lower and lower.
The production technology and methods of zinc alloy die castings in China mainly include casting technology, casting system, feeding system, air outlet, cooling system and special casting technology. China has a long history of casting, which can be traced back to 6000 years ago. As an ancient manufacturing method, the quality of large castings has a direct impact on the quality of products with the development of industrial technology. Therefore, casting plays an important role in the machinery manufacturing industry.