An inexpensive, environmentally friendly alternative to a toxic coating currently used in Australian naval helicopters has been developed at Monash University in collaboration with CAST Cooperative Research Centre in Melbourne.

The magnesium alloy used to house the gearbox of Royal Australian Navy SeaHawk helicopters is prone to severe corrosion in marine environments, costing millions of dollars in maintenance every year. To protect the alloy from corrosion, it is covered with a chrome-based coating that is toxic to humans and the environment.

Under joint supervision of the Defence Science and Technology Organisation (DSTO) and researchers at Monash and Swinburne Universities, PhD student Ms Parama Banerjee has developed a much-needed alternative which provides superior corrosion protection. It is made from a silicon-based material called silane.

“The silane coating is completely biodegradable and non-toxic so people can handle it safely. It also delivers the maximum corrosion resistance ever achieved for magnesium alloys.”

Ms Banerjee says while the new technology is still at a preliminary stage, it could be used to repair the corroded gearbox housings of SeaHawk helicopters in the near future.

DSTO worked with the CAST CRC—which specialises in industry-driven research into metals technology—to address the corrosion issues for magnesium alloys.

Photo: A non-toxic coating will reduce environmental and maintenance costs in Seahawk helicopters.

Credit: US Navy

CAST Cooperative Research Centre, Cathie Wilson, c.wilson@cast.org.au, www.cast.org.au