March 2023
The main use of zinc is galvanising steel…but what other end uses does zinc have? While zinc is most commonly, around 60%, used as a protective coating for steel to prevent rusting, it has many other critical uses.

 

The main end-use industry for zinc is construction, followed by transport and infrastructure. While most of the use in these industries is from galvanised steel consumption, there are other vital uses for zinc which cover a huge range of industries and applications.

 

 

Zinc Alloys

The second-largest end use for zinc is to create alloys with other metals.

 

Brass

Brass is the most common zinc alloy and is created by combining zinc and copper, generally in a ratio of around 35% zinc to 65% copper. The addition of zinc enhances the strength and pliability of the copper.

Brass has a wide range of industrial and commercial uses, including engine components, architectural features, piping and tubing, mechanical components such as gears or locks where low friction is required, and firearms casings. It is also widely used for commercial consumer products such as door handles, musical instruments and jewellery.

 

Solders

Zinc is also commonly alloyed with cadmium, lead and tin to create solders. Each alloy has a different use, where application methods or end-result qualities differ by necessity. A tin-zinc solder, for example, is used when a lower soldering temperature is required, often on or near electronic parts, and has a high tensile strength.

A zinc-cadmium solder, on the other hand, provides higher-temperature, stronger and more corrosion-resistant joints and can be used for soldering dissimilar metals together, it cannot however be used in food or drinking water processing machinery, as cadmium is a health hazard.  

 

Zinc Batteries

Traditional zinc-carbon batteries, used to power small portable devices, were the first available commercial batteries in the 1880s. While these have been widely phased out in favour of alkaline batteries, zinc chemistry batteries remain.

Zinc when alloyed with other metals has major potential in energy storage applications as an alternative to lithium-ion batteries. It improves upon existing energy storage and battery technologies by allowing for energy storage that is low-cost, safe, and long-duration.

Zinc-ion batteries can be used as an alternative to lithium-ion batteries, with benefits due to their increased safety and their stable supply chain. Zinc batteries are not flammable or subject to thermal runaway or off-gassing.

Aside from alloyed zinc batteries, there are numerous competitors in various stages of testing and development for new rechargeable zinc batteries, one of the main types of which are zinc-air batteries. Zinc-air batteries are lightweight, compact, and made of more sustainable, less flammable materials than other batteries.

However, they’re usually not rechargeable. Researchers have been working to modify the existing non-rechargeable chemistry with a different input method by using an electrolyte that contains water-resistant ions Zinc8 Energy Solutions has developed an innovative battery technology that uses zinc and air as fuel.

Power is used to generate zinc particles in a Zinc Regenerator. Oxygen is released into the atmosphere as a by-product. The zinc particles are then stored and maintained in a potassium hydroxide electrolyte until required. Whenever power is needed, the zinc particles are recombined with oxygen to generate electricity. The zinc oxide by-product is returned to a storage tank for later regeneration.

 

Zinc Oxide

Zinc oxide is the industrially most important zinc compound. Its applications are wide-reaching. Zinc oxide has a high refractive index, high thermal conductivity, binding, antibacterial and UV-protection properties. 

 

Rubber

The rubber industry accounted for around 41% of zinc oxide used in 2021. This was predominately attributed to the growing production of tires. The tire industry uses zinc to produce safe and durable tires. Zinc plays a critical and irreplaceable role in manufacturing tires. Zinc oxide is used as a vulcanising activator which turns soft, sticky rubber into stable, solid components that allow a tire to carry the weight of a vehicle and to stop safely.

 

Ceramics

The ceramics industry is the second-largest consumer of zinc oxide. The low expansion coefficient of zinc oxide makes it ideal for ceramic manufacturing since it improves ceramic elasticity. Other desirable properties include its relatively high heat capacity, high-temperature stability and thermal conductivity. In lesser amounts, zinc oxide gives a glossy appearance to ceramics, while in greater amounts will show as a matte finish.

 

Pharmaceutical

The human body contains around two to three grams of zinc. It is the second most common trace metal naturally found in the body after iron. Zinc is an essential trace element in the diet of all living organisms from bacteria to humans. Either too little zinc or too much zinc can be harmful and cause health problems.

Zinc oxide is a proven sunscreen as it’s a broad-spectrum UV absorber that reduces UV radiation in both the UVA and UVB range effectively. The amount of sun protective factor (SPF) in sunscreen is based primarily on the percentage of zinc oxide.

Zinc oxide also promotes wound healing, reduces inflammation, and keeps wounds moist and clean.

 

Dentistry

Zinc oxide eugenol (ZOE) is one of the most popular materials used in dentistry. It is commonly used as a dental cement, for dental liners and bases and it is used in dental impressions.  

 

Cosmetics

A wide range of cosmetic products, such as foundation, lip products, mineral make-up bases, face powder, hand creams, moisturizers, lotions, and ointments all use zinc oxide as it helps cosmetics to adhere to the skin. It also has proven to be both antibacterial and antifungal by destroying the cellular membranes of single-celled organisms.

 

Agriculture

Zinc is an essential micronutrient for both human and plant development. It has been labelled as a ‘lifesaving commodity’ by the UN due to zinc fertilisers' contribution to the realisation of the UN Sustainable Development Goal 2: Zero Hunger (SDG 2) by ensuring crops are productive and have the appropriate nutrition to nourish the world’s population.

Crop productivity will be critical to addressing the higher demand for food in the future. The use of zinc oxide-based fertilisers can help crops to be resilient to drought, salinity, and heat. A stable supply of zinc can also help crops reach higher productivity and yield levels.