MCrAlY (where M is Ni, Co or NiCo) coatings are used as single overlay coating or as bond coat for thermal barrier coating (TBC) systems. They can be obtained by plating using CrAlY as precursor powders in an electrolytic bath containing nickel and cobalt salt in solution. The size of the precursor CrAlY powders used was generally below 10 um.
As-plated coatings consisted of a random distribution of CrAlY particles in the Ni-Co matrix. The heat-treatment of the as-plated coatings at elevated temperature resulted in the development of a gamma and beta structure. Both as-deposited and oxidized coatings were characterized by optical, scanning electron microscope and electron beam microprobe. During oxidation the coatings formed alumina scale with a negligible amount of transient nickel and chromium oxides.
MCrAlY powder is used as a coating to protect parts from oxidation. Moreover it is applied as a bond coat for the thermal barrier coating required by various aircraft and industrial gas turbine components. Cobalt and nickel are typically used as a base for the undercoating to make the metallic intermediate layer ductile. Aluminum and chromium form a stable oxide layer that protects coatings from oxidation. Yttrium enhances the bonding of this oxide layer.In addition, the good wear resistance achieved by combining MCrAlY and aluminum oxide make it well suited for furnace rollers in steel factories.
MCrAlY coatings are the key to the performance and reliability of highly stressed turbine parts. The M in MCrAlY stands for the base metal, which is alloyed with yttrium, chromium and aluminum.
As a thermal spray powder manufacturer, Stanford Advanced Materials’ backwards integration of rhenium and tantalum containing MCrAlY powders and chemical overspray recycling put us in a unique position to offer exceptional supply security and quality.