Vitreous enamel coatings are prone to impact damage as a consequence of their low toughness. Previous attempts to improve this situation by adding fine aluminium powder particles have not been entirely successful because of the very high levels of contiguous porosity that result from the reaction of molten aluminium with hydroxyl ions. A new processing route is described that overcomes this problem and leads to high quality coatings having greatly improved impact resistance, excellent adhesion to steel substrates, and enhanced high temperature oxidation behaviour.MST/1015