Smart materials self-repair

Manufacturers have several ways to protect metals from corrosion. Painting with a waterproof polymer, electrolytically coating with zinc in galvanisation, or chrome plating are all effective methods. However, if the protective coating itself is damaged, air and moisture can attack the exposed metal. Dmitry Shchukin and Helmuth Möhwald of the Max Planck Institute of Colloids and Interfaces in Potsdam, Germany, and colleagues in the department of ceramics and glass engineering at the University of Aveiro, Portugal, have devised a new gel-like coating for metals and alloys. The smart coating not only protects the surface but repairs any cracks or holes that appear in the coating itself where rusting can start.¹