Scientists from St. Petersburg Polytechnic University have patented a unique aluminum alloy with a foam core, the use of which in shipbuilding can significantly increase the buoyancy of aluminum boats.
«If the material is highly porous, its density can be reduced to the density of water or even lower. This means that the material will not sink. The use of such materials in the shipbuilding industry will ensure unsinkability even in case of hull ruptures», - said Oleg Panchenko, Deputy Head of the Laboratory of Lightweight Materials and Structures, SPbPU.
It means that the vessel made of porous aluminum will have high reserve buoyancy in case of sinking.
The sandwich construction of the new material means it has greater strength and stiffness than traditional aluminum for the same weight. However, this advantage comes with a caveat: according to experienced surveyors, contact with salt water can thin the already thin walls of aluminum foam bubbles, then lead to a loss of structural strength over time.
Thanks to this technology, the porous core is reliably protected by an outer layer of metal. Nevertheless, any penetration of water inside may still pose an additional corrosion risk compared to the solid material. According to Chinese scientists, this risk can be reduced by creating the aluminum foam with an alloy containing one to two percent manganese.
