Slurry aluminizing of turbine blades

This paper presents the results of a study on the application of a slurry method to produce aluminide coatings on aircraft engine turbine blades. The coating was produced on ZS6K alloy blades by 1, 2 and 3 times spray painting with intermediate drying followed by diffusion annealing in Ar atmosphere for 2, 4 and 6 hours at 900, 950 and 1000°C. The coatings were evaluated with consideration of thickness structure and aluminum content. The results indicated that the use of single-painting did not allow - regardless of temperature and annealing time - to obtain a uniform aluminide coating. The use of two-time painting and diffusion annealing at time 4 hours makes it possible to obtain coatings with a thickness of 60–80 μm containing 26–30 wt. % of aluminum. Three-coat painting makes it possible to obtain coatings close to 100 μm thick containing 28–32 wt. % of aluminum.