Fibre-reinforced composites self-heal at sub-zero temperatures

The team, led by the University of Birmingham and Harbin Institute of Technology in China, said the method could be applied to fibre-reinforced materials used in situations where repair or replacement is challenging such as offshore wind turbines, or even in aircraft during flight. A paper describing the work has been published in Royal Society Open Science.

Under the right conditions self-healing composites have been shown to exhibit favourable properties. Previous research has yielded efficiencies above 100 per cent, indicating that the function of the healed material can be better than that prior to damage.

Until this paper, however, healing was deemed insufficient in conditions including very low temperature.

Key to self-healing at low temperatures is the way in which the new structural composite maintains its core temperature. To do this, three-dimensional hollow vessels (that deliver and release healing agents), and a porous conductive element (to provide internal heating and to defrost when necessary) are embedded in the composite.