An inexpensive, eco-friendly coating being developed Down Under may provide a successful corrosion-control alternative to a toxic coating now used in naval helicopters, researchers say.
The non-toxic coating holds promise for protecting the magnesium alloy that houses the gearbox of Royal Australian Navy SeaHawk helicopters. The multi-mission maritime helicopter is prone to severe corrosion in marine environments, requiring millions of dollars in maintenance every year.
Airman Justin R. Blake / U.S. Navy
|Its marine service environment makes the Seahawk helicopter prone to severe corrosion.|
The coating was developed by doctoral student Parama Banerjee at Australia’s CAST Cooperative Research Centre, which conducts industry-driven research in metals technology.
“The results are encouraging, but the coating can only be used after rigorous field testing, which might take some time,” Banerjee said in an email.
‘Maximum Corrosion Resistance’
The project is the result of collaboration between CAST CRC and Australia’s Defence Science and Technology Organisation (DSTO). Researchers at Monash and Swinburne Universities helped supervise the research.
Banerjee’s coating is made from silicon-based silane, an environmentally friendly material that researchers say provides superior corrosion protection.
The silane deposition on the metal surface is performed through a sol-gel process, Banerjee said.
“Although we call the coating ‘silane coating’ (just a nomenclature), during sol-gel processing, silane is transformed into silanols and siloxanes, which are chemically different than silane,” she said.
“Furthermore, the thin solid film formed on metal surface cannot be considered chemically similar to the silane precursor. “
The result, Banerjee said: “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.”