Zinc alloy die casting material and characteristics

Die-casting zinc alloy, that is, the material of die-casting parts, in order to obtain excellent die-casting parts, in addition to having a properly designed part structure and shape, a perfect die-casting mold, an accurate die-casting process plan and a die-casting machine with excellent process performance, it is also necessary to have Die-cast zinc alloy material with excellent performance.

Features of die-cast zinc alloy:

Zinc alloy has the characteristics of small crystallization temperature range, low melting point, easy filling and forming, not easy to loose, not easy to produce mucous membrane, and can prolong the life of die casting mold. Zinc alloy has good mechanical properties, and can be die-casting of various complex and thin-walled castings.

After the zinc alloy is die-casted into a casting, the dimensional shrinkage will occur, and the alloy composition has a great influence on the dimensional change. The size of the zinc alloy die casting without copper is relatively stable, and the size of half of the zinc-aluminum alloy die casting does not change much. . The working range of zinc alloy is narrow. When the temperature is lower than 0 °C, its impact toughness decreases sharply, and when the temperature exceeds 100 °C, the mechanical properties decrease significantly. Zinc alloy is easy to age, and the aging phenomenon is manifested as volume expansion, strength reduction, and plasticity reduction. This is mainly due to the low solubility of impurities such as lead, tin, and cadmium in zinc alloys. Therefore, the impurity content should be strictly controlled during material selection and smelting.

Application of die-casting zinc alloy:

Products made of zinc alloy die-casting have excellent surface quality and have been widely used in the manufacture of toys, tableware, locks, hardware decorative parts, electrical and electronic castings, bathroom accessories, auto parts, zippers, metal buckles, watch cases, fans , daily necessities, household appliances, photographic equipment, audio, mechanical and electrical products and parts.

Control of zinc alloy slag amount:

1. Strictly control the smelting temperature, the higher the temperature, the more zinc slag.

2. Avoid stirring the zinc alloy liquid in the zinc pot as much as possible. Any kind of stirring will lead to more contact between the zinc alloy liquid and the oxygen atoms in the air, thereby forming more zinc slag.

3. Do not scrape the slag too frequently. When molten zinc alloys are exposed to air, oxidation occurs, forming dross. Retaining a thin layer of scum on the surface of the pot will help protect the liquid in the pot from further oxidation.

4. When scraping slag, use one more hole (about 6mm in diameter) disk-shaped slag scraping scraper, gently scrape it under the scum, avoid stirring the alloy liquid as much as possible, pick up the scraped slag, and scrape the slag on the zinc. The side of the pot is gently knocked, and the metal liquid flows back into the zinc pot.

The main parameters in the die casting process involve pressure, speed, temperature and time. These parameters affect and restrict each other. The process of filling the cavity with molten metal during die casting is to dynamically balance the process factors such as pressure, speed, temperature and time. During the process, adjusting a parameter will cause changes in the corresponding process parameters. Therefore, it is very important to select each process parameter correctly. The careful selection of die-casting coatings and reasonable spraying operations are an important factor to ensure the quality of die-casting parts and improve the life of die-casting molds.