Naval architects are experimenting with new materials to make their ships lighter, stronger and more profitable.
By Dennis O’Neill
For most of human history, ships were built out of wood. With the industrial revolution, iron arrived. And for the last century or so, steel has dominated.
Now, however, ship designers are searching for alternatives to steel that will improve performance and, at the same time, reduce fuel costs, maintenance needs and environmental impact.
Aluminium and carbon fibre currently lead the field: HSC Francisco, reportedly the world’s fastest ferry, which travels across the River Plate between Uruguay and Argentina at over 50 knots, is built from aluminium, while the new M80 Stiletto, a US Navy SEALs stealth craft that can hit 60 knots in rough seas, is made entirely from an advanced carbon composite. Details of the latter are obviously classified.
Other exciting possibilities are coming down the track, including aerographite (one of the world’s lightest materials, made of microscopic carbon tubes), and transparent aluminium (a ceramic alloy that’s resistant to corrosion).
But the most promising prospect appears to be graphene – atom-thick sheets of carbon that are exceedingly strong. Researchers have found that adding even very small amounts of graphene to metals and plastic composites render the materials a great deal stronger and lighter.
Last year, Australian materials specialist Talga started an 18-month ocean-going trial on a container ship featuring its new graphene-enhanced primer coating, Talphene.
“Talphene is highly suitable for all types of ships,” says Talga’s managing director Mark Thompson. “It offers amazing environmental and economic outcomes – including improved corrosion resistance and decreased metallic paint loss into oceanic ecosystems, as well as increased profitability through reduced maintenance.”
Image credit: Pete Wright, Unsplash
The US Navy, meanwhile, is busy developing a range of what it calls “omniphobic” coatings for its next generation of surface ships, submarines and unmanned underwater vessels. These coatings aggressively repel water, significantly reducing hydrodynamic drag, and potentially saving the US government hundreds of millions of dollars in fuel costs.
“Up to 80 per cent of a ship’s fuel consumption is used to maintain its speed and overcome hydrodynamic drag,” explains Dr Ki-Han Kim of the US Navy’s sea warfare and weapons department. “The development of these exciting new materials allows our vessels to take on a far greater range of military operations.”
Image credit: Asael Pena, Unsplash
Owners of the world’s largest superyachts have also played a significant part in the development, and funding, of advanced new materials. Interestingly, though, some leading superyacht builders are now reverting to steel-built vessels, because steel, unlike complex composites, can be recycled easily and safely.
In fact, others are suggesting that ship designers and material scientists should start taking more interest in a material that’s not only light and extremely strong, but also highly versatile and perfectly in tune with our need for more environmental responsibility. It’s called wood.