UAE seeks competitive edge in aerospace anti-corrosion project

Aeroplanes are marvelous – and even better when they don’t rust to pieces in the air.

Ensuring that they don’t is quite a challenge. The air they fly through is moist – especially in coastal areas like the UAE – and the air is often extremely hot or perishingly cold, and of variable pressure depending on the altitude.

There are also some extremely nasty chemicals in the upper atmosphere that are prone to corroding components made of metal or plastic.

That is not what you want when the lives of hundreds of passengers depend on the structural integrity of each and every component.

To withstand these adverse exposures, many aircraft parts are plated with electrolytic hard chromium (EHC) – a thin layer of the metallic element of chromium that helps surfaces resist corrosion, while hardening and making them easier to clean.

But while chrome plating is the current benchmark for aircraft surface protection, it is far from friendly to the environment, releasing many toxic and dangerous materials into the atmosphere.

Researchers at the Masdar Institute are hoping to come up with something better. Mubadala Aerospace has funded a project that seeks to use cutting-edge thermal spray techniques to coat aircraft landing gears to protect against corrosion and wear resistance. The project is a collaborative venture with Abu Dhabi Aircraft Technologies (ADAT), a Mubadala subsidiary.

The process uses heat to turn a material, metallic or non-metallic, into molten droplets. The droplets are then propelled on to a surface, creating a protective layer.

It is a less environmentally hazardous way of applying a coating, doing away with the carcinogenic hexavalent chromium needed in EHC plating baths.

It is also more flexible. Thermal spray coating systems can be scaled down and made portable, allowing worn or damaged parts to be repaired on the spot, rather than having them dismantled, replaced or sent to a distant machine shop.

The only question, then, is how best to apply thermal spray coating to get maximum advantage while keeping costs to a minimum. To this end, the Masdar Institute team is conducting a comprehensive study of the various parameters that affect the coating quality. They have identified ideal operating parameters to ensure the strongest and best quality protective coating for a plane. With this information, ADAT will be able to take the utmost advantage of the benefits of thermal spray coating.

In addition to being environment-friendly, thermal spray coatings perform better and are more reliable than other methods of surface protection.

The methodology and data this project generates could provide Abu Dhabi’s fledgling aerospace sector with an economic edge over competitors, while meeting the highest health, safety and environmental impact standards.

The technology is also of interest to other industries, including car production, oil and gas, and even military defence. Developing Abu Dhabi’s know-how in this area should provide the Emirates with a valuable product and service to tap into a global market that is expected to be worth almost US$14 billion next year.

Dr Tariq Shamim is a professor of mechanical engineering at the Masdar Institute of Science and Technology.