کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
8030001 1517654 2013 22 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Microstructure and oxidation behavior of Al and Hf co-deposition coatings on nickel-based superalloys
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد فناوری نانو (نانو تکنولوژی)
پیش نمایش صفحه اول مقاله
Microstructure and oxidation behavior of Al and Hf co-deposition coatings on nickel-based superalloys
چکیده انگلیسی
This study focuses on investigating the microstructure and oxidation behavior of Al and Hf co-deposition diffusion coatings deposited by Pt electroplating followed by combined aluminizing and hafnizing using the pack cementation technique. The composition (in wt.%) of the packs was 2NiAl-2NH4Cl-xHf-(96 − x)Al2O3 with different Hf levels (x = 2, 6, 12 and 16), and the corresponding microstructure of the coatings was γ-Ni + γ′-Ni3Al, NiAl + Al16Hf6Ni7, Al16Hf6Ni7 and Al1.65HfNi0.35, respectively. In the post heat-treatment process, with Hf and Al diffusing towards the superalloy substrate and Ni diffusing in the opposite direction, Al16Hf6Ni7 and Al1.65HfNi0.35 were transformed into Ni3Al + Al3HfNi12 and NiAl + Al3HfNi12, respectively. The isothermal oxidation tests at 1000 °C in air indicated that the coating formed in the packs containing 2 wt.% Hf had the lowest weight gain, while the weight gain of the coating formed in the packs having 6 wt.% Hf was the largest. The mechanisms of Hf-rich phase formation and their effects on oxidation resistance of the coatings were discussed.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Surface and Coatings Technology - Volume 224, 15 June 2013, Pages 57-61
نویسندگان
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