Zinc: properties, grades and applications / Articles

Zinc (Zn) is a transition metal that is brittle at room temperature but ductile when heated, with a bluish-silvery colour, occupying a strategic position among non-ferrous metals. In terms of global production and consumption, zinc consistently ranks among the top four, behind only aluminium, copper and lead. Its unique ability to protect steel from corrosion through hot-dip galvanizing has made this metal indispensable in construction, automotive and infrastructure projects. In addition, zinc is a critically important component for foundry alloys, the chemical industry, pharmaceuticals and new energy storage technologies.

Chemical Nature and Physicochemical Properties

Zinc is a metal with atomic number 30 and atomic mass 65.38 g/mol. The density of zinc is 7.13 g/cm³. Its melting point is 419.5 °C, and its boiling point is 906 °C. One of the key features of zinc is its relatively low melting point, which makes it convenient for die casting and processing.

At room temperature, zinc is brittle, but when heated to 100–150 °C it becomes ductile and easily rolled and drawn. With further heating above 200 °C, the metal becomes brittle again. On the zinc surface, when interacting with moist air, a thin and dense film of zinc carbonate or oxide forms, which reliably protects the metal from further oxidation. This ability ensures the durability of zinc coatings. Zinc actively reacts with acids and alkalis, displacing hydrogen.

Classification, Grades and Standards

In Russia and CIS countries, requirements for primary zinc in ingots and blocks are established by GOST 3640-94. The standard regulates chemical composition, delivery form and marking. Depending on the zinc content and impurities (lead, cadmium, iron, copper, tin, arsenic, antimony), the following main grades are established:

TsV0 (high-purity zinc, 99.995%) — the purest metal, supplied in the form of ingots and blocks. Used for critical chemical processes, pharmaceuticals and special alloys.
Ts0A (99.98%) and Ts0 (99.975%) — high-quality grades used for the production of zinc white, foundry alloys and electroplating coatings.
Ts1 (99.95%) — widely used for hot-dip galvanizing and alloy production.
Ts2 (99.9%) — used for less critical coatings and alloys.
Ts3 (99.85%) — used for steel production and certain alloys.

Products are supplied in the form of ingots weighing 19–25 kg (packed in bundles up to 1000 kg) or large blocks weighing 1000 and 2000 kg. For foundry production, zinc alloys such as ZAM4-1o (zinc-aluminium-copper) are also produced, which are regulated by separate standards.

Production Technology

The main raw material for zinc production is sulphide polymetallic ores containing sphalerite (ZnS). The technological chain includes ore mining and beneficiation by flotation to obtain zinc concentrate.

Two main industrial methods for producing metallic zinc are then used:

Pyrometallurgical (distillation) method — roasting the concentrate to convert sulphide to oxide, followed by reduction with carbon at high temperatures and distillation of zinc vapours with subsequent condensation.
Hydrometallurgical (electrolytic) method — roasting the concentrate, leaching zinc oxide with sulphuric acid, purifying the solution from impurities and electrolysis with deposition of pure zinc on cathodes. This method ensures high metal purity and is currently dominant in world practice.

To obtain ultra-pure zinc (6N and above), vacuum distillation and zone melting are additionally used.

Applications

Hot-dip galvanizing. This is the largest area of zinc consumption — it accounts for about 50–60% of global demand. Zinc coating is applied to steel structures, sheets, pipes and fasteners to protect against atmospheric corrosion. Galvanized steel is indispensable in the construction of bridges, buildings, infrastructure, automotive and household appliances.

Foundry alloys. Zinc alloys (e.g., ZAM) are used for die casting of automotive parts, electronics, household appliances, sanitary ware and toys due to their low melting point, high fluidity and good machinability.

Chemical industry. Zinc is used to produce zinc white (ZnO), which is used in the paint, rubber, ceramic and pharmaceutical industries. Zinc oxide is also an important component of sunscreens and antiseptic ointments.

Batteries and accumulators. Zinc is a key component of zinc-air cells and is also used as an anode in some types of batteries. The development of energy storage technologies stimulates demand growth in this segment.

Agriculture and health. Zinc is an essential trace element for plants, animals and humans. It is used for the production of zinc micronutrient fertilizers and dietary supplements.

Other applications. Zinc is used in the production of brasses, typographic alloys, for sacrificial protection (sacrificial anodes), and in the production of semiconductors (ZnSe, ZnS).

Safety and Storage

Zinc and its inorganic compounds belong to moderately hazardous substances. Dust and fumes of zinc oxide, when inhaled, can cause irritation of the respiratory tract and the so-called "metal fume fever." When working with molten zinc and dust, personal protective equipment (respirators, safety goggles, protective clothing) must be used and effective ventilation must be ensured. Zinc is non-flammable. Storage of zinc in ingots and blocks should be carried out in dry, closed warehouses or on areas with hard surfacing, protected from moisture and contamination.

Market and Trends

The global zinc market demonstrates steady dynamics. In 2025, global refined zinc consumption was estimated at approximately 13.66–13.8 million tonnes, with production almost matching demand, and the market balancing on the edge of a small deficit or surplus. It is projected that by 2032, the market volume in physical terms may reach 46.4 million tonnes (including all forms of concentrate and metal) with a compound annual growth rate of about 7.3% in certain segments.

Key growth drivers are infrastructure construction, especially in developing countries, the recovery of the automotive industry and the shift to lighter and more corrosion-resistant materials. A promising direction is the development of zinc-air batteries and renewable energy technologies. The largest zinc producers remain China, Peru, Australia, India and the USA. An important trend is the development of zinc recycling, as zinc is a 100% recyclable material.

Conclusion

Zinc remains a fundamental industrial metal, ensuring the durability of steel structures, the development of foundry technologies and progress in the chemical and energy industries. Understanding the grade composition according to GOST 3640-94, production technologies and safety requirements is the basis for competent material selection and the organisation of efficient supplies.