Abstract: The braze repair process of cracks in turbine guide vanes made from superalloy K3 is investigated in this paper.The removal of oxides from the surface of cracks is carried out using cleaning with fluoride in vacuum and in argon.AES with sputter etching are used to analyse and investigate the removal of oxidies from the surface of cracks,the stripping of coating of the aluminide.type of vanes.Finally,the cleaned cracks are repaired by brazing.The results show that the braze repair technique of turbine guide vanes is successful and can be applied to the repair of vanes and other aeroengine components made from other superalloys.