Adhesion properties of aluminide coatings deposited via CVD in fluidised bed reactors (CVD-FBR) on AISI 304 stainless steel

Aluminide coatings are widely used to protect a vast variety of metals and alloys for high temperature applications. Under certain environments, these are not only designed to improve high temperature corrosion, but also erosion. Therefore, the mechanical properties (such as toughness) of these protective coatings obtained by CVD-FBR are of prime importance taking into account the advantages of this coating technique. In this paper, preliminary studies of mechanical characterisation of aluminide coatings obtained on AISI 304 stainless steel by CVD-FBR deposited at 525°C and different processing times are presented. The effect of a subsequent thermal treatment of the aluminide coatings has also been investigated. From the results, the relationship between coating process, heat treatment, and toughness is established.