The invention relates to a thermal barrier coating removal method. A metal component (32) having a thermal barrier coating is located in a vessel (12) for containing an inert liquid reservoir. The vessel (12) has a releasably sealable closure (14) so as to allow the vessel interior to be maintained at an elevated pressure in use. The vessel is heated and the liquid therein is maintained at a temperature greater than 100° C. for an extended period of time such that thermal barrier coating breaks up as a result of internal stress caused by a crystal structure change in the thermal barrier coating.