Parameters Evaluation of Bond-Coat Deposited by CO₂ Laser Beam for Aeronautical Turbine Blades

Abstract:

The high temperature environments where aeronautical turbine blades are exposed makes mandatory the use of ceramic coatings. A bond coat comprised by a MCrAlY alloy (M=Co, Ni) is necessary to match the blade metallic substrate with the ceramic, also acting as a corrosion barrier. The laser treatment of metals and alloys is based in the surface local heating, followed by high cooling rates. The laser parameters such as scanning speed and laser power, plays an important role on the morphological, mechanical and chemical characteristics of the deposited material. In the present investigation, the NiCrAlY deposition was performed in stainless steel substrates with a CO₂ laser beam. Different laser parameters of scanning speed and number of scanning cycles were implemented. The samples were characterized by optical microscopy and measurements of Vickers hardness. The results show that it is possible to achieve coatings with high hardness, free of pores or any pronounced defects, metallurgically bonded to the substrate.

• Periodical: Materials Science Forum (Volume 869)
• Pages: 685-688
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.869.685
• Online since: August 2016
• Authors: Viviane Teleginski, Júlio César Gomes Santos, Daniele Cristina Chagas, Jéssica Fernanda Azevedo, Ana Claudia Costa Oliveira, Getúlio de Vasconcelos
• Keywords: Laser Treatment, NiCrAlY, Turbine Blades

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