Quantitative Evaluation of Alitize Coating on ŽS6K Ni-Base Superalloy

Abstract:

The aerospace industry is one of the biggest consumers of advanced materials because of its unique combination of mechanical and physical properties and chemical stability. Highly alloyed stainless steel, titanium alloys and nickel based superalloys are mostly used for aerospace applications. The aim of the work is to evaluate protective Al Si coating applied by diffusion annealing on substrate, Ni base superalloy ZS6K. This superalloy is used for turbine blade production in aero jet engine DV 2. Using of protective alitize coating provides an increasing of heat resistance of superalloy surface and increases working temperature up to 800°C. However, overcrossing of working temperature range (for ZS6K turbine blades it is from 705°C to 750°C) sometimes happen and that is the reason for detailed study of protective coating degradation. The alitize coating were evaluated in starting stage and after various time of regular loading in real aero jet engines DV 2. Coating and its degradation was evaluated with help of quantitative metallography methods (metallography software NIS Elements) and colour contrast as well.

• Periodical: Materials Science Forum (Volume 782)
• Pages: 578-583
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.782.578
• Online since: April 2014
• Authors: Juraj Belan*
• Keywords: Alitize Layer, Colour Contrast, Ni Based Superalloy, Quantitative Evaluation, Working Conditions

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