Abstract: A method of providing a protective, corrosion-resistant thin coating of a MCrX alloy on a carbon or low-alloy steel pipe or tube where M is one of nickel, cobalt or iron or combination thereof and X is one of molybdenum, silicon, tungsten or combination thereof, and heat treating the coating to metallurgically bond the coating onto a steel substrate of the pipe or tube. The coating may be deposited in one or two layers by plasma transferred arc deposition or may be deposited as a slurry coating or thermal spray coating with sintering of the coating. The steel substrate is prepared for coating by at least one of boring, honing, bright finishing, grit blasting, grinding, chemical pickling or electro-polishing of the substrate.

Abstract: A method of providing a protective, corrosion-resistant thin coating of a MCrX alloy on a carbon or low-alloy steel pipe or tube where M is one of nickel, cobalt or iron or combination thereof and X is one of molybdenum, silicon, tungsten or combination thereof, and heat treating the coating to metallurgically bond the coating onto a steel substrate of the pipe or tube. The coating may be deposited in one or two layers by plasma transferred arc deposition or may be deposited as a slurry coating or thermal spray coating with sintering of the coating. The steel substrate is prepared for coating by at least one of boring, honing, bright finishing, grit blasting, grinding, chemical pickling or electro-polishing of the substrate.

Abstract: A method for protecting high temperature stainless steel from coking and corrosion at elevated temperatures in corrosive environments, such as during ethylene production by pyrolysis of hydrocarbons or the reduction of oxide ores, by coating the stainless steel with a coating of MCrAlX in which M is nickel, cobalt, iron or a mixture thereof and X is yttrium, hafnium, zirconium, lanthanum or combination thereof deposited onto and metallurgically bonded to the stainless steel by plasma transferred arc deposition of atomized powder of MCrAlX. The coating has a thick, dense, continuous and smooth transition region providing an effective metallurgically bond of the coating with the stainless steel. The coating retains a relatively high aluminum content which permits generation of an adherent alumina layer on the surface, providing good resistance to high temperature oxidation together with good anti-coking and hot erosion resistance properties.