Design and heat treatment of plasma sprayed ZrO_2 thermal barrier coating

摘要

Design adn heat treatment of plasma sprayed ZrO_2 thermal barrier coatings (TBCs) were described.It was found that the optimization of the compositions of ZrO_2 and MCrAlX alloys was important for improving the properties of TBCs.Graded coating is a new type of TBC,which cna remarkaly relax thermal stress,improve thermal shock resistance,and offer an effective way of increasing the coating' sthickness necessary for improving its heat insulating propety.the thermal shock resistance was improved markedly by vacuum heat treatmen tdue to the enhanced adhesion between the coating and substrate,and the oxidatin resistance of the coatings improved by laser remelting due to the increased relative density of ZrO_2 surface layer.It was however found that the thermal shock resistance was deteriorated by cracks formed within the oating during laser remelting.