Zinc dust is a functional powder material that plays a significant supporting role in the national economy, possessing unique physical and chemical effects. It is widely used in industries such as coatings, chemicals, metallurgy, pharmaceuticals, fuels, pesticides, electronics, and batteries. Zinc dust can be classified into two types based on particle structure: granular and flake.
Classification and Preparation Methods of Zinc Dust
1. Granular Zinc Dust: This type of powder has a structure that approximates a spherical shape and mainly includes national standard zinc dust and ultrafine high-activity zinc dust. Compared to the former, the latter has a higher metallic zinc content, lower impurity content, smooth and clean surfaces of micro-spherical particles, good activity, minimal surface oxidation, narrow particle size distribution, and good dispersion performance. It is considered a key new product. The largest application of ultrafine high-activity zinc dust is in coatings and anti-corrosion, primarily for producing zinc-rich coatings or directly coating anti-corrosion layers. Among these, the ultrafine zinc dust with a particle size of less than 28 μm is most commonly used in coatings. The application of high-performance ultrafine zinc dust can save resources and improve resource utilization, with broad market prospects. There are many preparation methods for granular zinc dust, which can be divided into two main categories: pyrometallurgical and hydrometallurgical methods.
2. Flake Zinc Dust: This type of metallic powder has a flake-like structure with a large aspect ratio (30-100), providing good coverage and shielding properties. It is primarily used to prepare high corrosion-resistant zinc-chromium coatings or zinc-aluminum coatings, serving as corrosion protection for small steel structures. The anti-corrosion coatings made with flake zinc dust have a layered arrangement of zinc flakes, requiring less metal powder, resulting in dense coatings with good corrosion resistance. Notably, zinc-chromium coatings made with flake zinc dust exhibit significantly better salt spray corrosion resistance than electroplated and hot-dip galvanized zinc, and they produce less pollution, meeting environmental requirements. The common preparation methods for flake zinc dust generally include two: ball milling and physical vapor deposition (PVD).
Applications of Zinc Dust
- Chemical Industry: Zinc oxide is widely used as a catalyst and a desulfurizing agent.
- Coatings Industry: Besides providing coloring and covering properties, zinc oxide serves as a corrosion inhibitor and a luminescent agent in coatings, as well as a pigment in paints and a filler in rubber.
- Pharmaceutical and Food Industries**: Zinc oxide has detoxifying, hemostatic, and tissue-repairing functions, used in soft ointments, zinc paste, and adhesive plasters.
- Glass Industry: Zinc oxide is used in specialty glass products.
- Ceramics Industry: Zinc oxide acts as a flux.
- Dyeing Industry: Zinc oxide is used as a dyeing inhibitor; nano zinc oxide, due to its fine particles and high activity, can lower the sintering temperature of glass and ceramics.
- Electronics Industry: Zinc oxide is not only a primary raw material for varistors but also a major additive for magnetic and optical materials.
Post time: Feb-14-2025
