Protection of carbon steels and refractory metals against oxidation by silicon –containing ceramic- type coatings

The nickel and cobalt-based super-alloys which are favored in applications related to space/aviation systems as well as the energy conversion systems are very close to their high-temperature limits. From the thermodynamic point of view, increases in temperature results in higher efficiencies for combustion systems. Thus, materials which are resistant to high temperatures with respect to strength as well as to oxidation are required. In this study, application of silicon and aluminum-containing coatings to refractory metals such as niobium and molibdenum, which have low oxidation resistance, are investigated. Similar type of coatings are also applied to a carbon steel (AISI 1040) samples. Internal structures as well as the oxidation behaviours of the coatings, produced by the pack-cementation technique, are discussed in this Thesis work.