COMPOSITE MATERIAL COATED WITH GRADIENT STRUCTURE USING CERAMIC POWDER AND METAL POWDER AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To obtain a composite material coated with a gradient structure obtained by using a ceramic powder and a metal powder and to provide a method for producing the same. ;SOLUTION: The method for producing the composite material comprises a step of forming a coating film having a gradient structure consisting of a ceramic or a metal on a ceramic or metal base materiel in order to relax the residual stress which may be generated by the difference of the coefficients of the thermal expansion of the ceramic base material or the metal base material and the coating film, thereby enhancing the stability of the coating film. As the ceramic or the metal for forming the coating film, a mixed powder which is obtained by combining a ceramic or a metal having a coefficient of the thermal expansion nearly equal to that of the base material and a ceramic or a metal having a coefficient of the thermal expansion different from that of the base material is used. By utilizing this method, the composite coated with the gradient structure can be obtained without pre-treatment processes such as a process for making the surface of the substrate coarse.;COPYRIGHT: (C)2001,JPO