Re ALLOY COATING FOR DIFFUSION BARRIER

摘要

A Re alloy coating for a diffusion barrier applied to a substrate,characterized in that it contains Re in an atomic percentage not less than 30 % and less than 90 %,at least one element selected from Cr,Mo and W in a total atomic percentage of not less than 5 % and less than 60 %,and at least one element selected from Ni,Fe and Co,and inevitable impurities in the balanced percentage.A layer having a desired alloy composition can be formed on the barrier coating by the surface coating method or through the diffusion of a component of the substrate,and when the barrier coating is subjected to a homogenization heat treatment and thereafter a cementation layer containing at least one element of Al,Si and Cr is laminated on the barrier coating,none of these elements substantially diffuses.Further,a stress relaxing layer comprising an alloy containing Re can be inserted between the substrate and the barrier coating.The Re alloy barrier coating allows the suppression of the deterioration of a substrate and a corrosion−resistant coating layer due to the reaction of the substrate and the coating layer,which has conventionally been a severe problem in the field of corrosion−resistant coatings such as a ceramic coating for heat shielding on a substrate made of e.g.a nickel base alloy,Al(or Cr or Si)pack cementation,thermal spraying and the like,and thus allows the increase of the life of a device.