Abstract: An abradable seal coating for application to one of a pair of members having relative rotational movement and its method of manufacture are described.The abradable seal coating comprises a two phase composition consisting of a first phase of a metallic alloy matrix of approximately 88% aluminium - 12% silicon, and a second phase of an organic dispersoid material. The first and second phases are codeposited onto a substrate in the ratio 80:20 respectively.The two phases are modified after codisposition onto the substrate by heat treating at a temperature of 450.degree. C. for about sixteen hours. The heat treated coating can be used at elevated temperatures and has improved abradability whilst maintaining its integrity.

Abstract: A powder suitable for flame spraying which is a composition of an admixture of particles, 20-40% by volume of the particles being an alloy such as a nickel base alloy or cobalt base alloy, each containing aluminium and chromium and the balance of the composition are hollow glass particles, each hollow glass particle being coated with a nickel base alloy or cobalt base alloy, each containing aluminium and chromium. The powder, when flame sprayed, is effective as a thermal barrier which is resistant to thermal shock and oxidation.

Abstract: A powder suitable for flame spraying comprising particles of an alumino silicate glass, each of the particles being hollow and coated with an alloy containing, by weight, 80% nickel, 2.5% aluminium, 15.7% chromium and 1.8% silicon. The resultant coating is particularly suitable for use as a thermal barrier.