Three technologies used to control corrosion — hot-dip galvanizing, anodic protection and nanotechnology — are successfully combating harsh environmental conditions and leading to longer usable service lives and increased safety.

These technologies are being used across the world for automobiles, storage tanks, bridges, large transport vehicles and work machinery. Here is a look at some recent research in each area.

Nanotechnology

Nanotechnology continues to offer the most promising solution for corrosion protection. The newest additive, in development by the Johns Hopkins University Applied Physics Laboratory and the Office of Naval Research since 2008, is a powder that can be stirred into ordinary paint.

This additive, called polyfibroblast, is composed of microscopic nanopolymers that are filled with oily liquid; when damaged, the materials inside these spheres coat the exposed metals with a water-repellent coating. This self-healing paint was created specifically for the harsh use and environments of tactical and military vehicles.

In laboratory experiments performed to mimic the effects of the elements, polyfibroblast prevented rust when exposed to salt fog continuously for six weeks. Field tests also show that nanotechnology has a promising future in applications to prevent corrosion.

Anodic/cathodic protection

World-class research at the Leeds Civic Centre has led to breakthroughs of corrosion repair and prevention in construction materials such as concrete and mortar. The potential for this type of product is immense as bridges around the world face harsh environmental conditions and could benefit from regular maintenance and structural strengthening.

The research showed that bonding carbon-fiber (CF) fabric or rods using impressed current cathodic protection (ICCP) anodes successfully increased flexural strength. CF rods or fabrics can be used to continuously increase the strength of corroded concrete.

This system has been put to trial use at Leeds, with great results proving that it can be used to repair corroded reinforced concrete structures. It is expected to lower costs and lead to easier maintenance where it is applied.

American Galvanizers Association
A screenshot of the new mobile app developed by the American Galvanizers Association (AGA).

Hot-dip galvanizing

Hot-dip galvanizing (HDG) remains one of the most utilized methods of corrosion protection because it is relatively maintenance-free and economical. Certainly, it has to be properly used for maximum performance, and a new mobile app developed by the American Galvanizers Association (AGA) aims to ensure that coating thickness, appearance and finish, and adherence meet the requirements for optimal use.

The information is contained in a photo-based application for architects, engineers and inspectors in the field. They can compare what they are examining with optimal outcomes of the galvanizing process to determine if the product meets stated requirements for the project. The app is available for both Apple and Android-based devices.

Nanotechnology is being utilized in the hot-dip galvanizing process as well; recently, NEI Corporation introduced a self-healing clear coating, Nanomyte TC-5001. It is a single-component coating that improves corrosion protection for zinc-plated and HDG steel. It can be applied by dipping, spray coating or brushing.

Testing shows that it can protect against harsh operating and environmental conditions. This coating shows potential for hardware, automotive use, farm equipment and outdoor applications such as street lights and electric towers.

Nanotechnology is proving indispensable in advancements in many industries, from the medical industry to electronics, oil and gas. When it comes to corrosion prevention, we can only expect further developments that make the use of steel less expensive and free of continual maintenance needs.