کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1448083 988664 2009 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Structure of NiCrAlY coatings deposited on single-crystal alloy turbine blade material by laser cladding
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد سرامیک و کامپوزیت
پیش نمایش صفحه اول مقاله
Structure of NiCrAlY coatings deposited on single-crystal alloy turbine blade material by laser cladding
چکیده انگلیسی

In the present work single and multiple layer NiCrAlY coatings were produced by laser cladding on (100) single-crystalline substrates of SRR99 Ni-based superalloy. Detailed structural characterisation and texture analysis by optical microscopy, scanning electron microscopy, X-ray diffraction and Rutherford backscattering showed that the NiCrAlY coatings consisted essentially of γ phase with yttrium oxide (Y2O3) and a small proportion of yttrium–aluminum garnet (Al5Y3O12) precipitated in the interdendritic regions. The coatings presented a columnar dendritic structure grown by epitaxial solidification on the substrate and inherited the single-crystalline nature and the orientation of the substrate. The coating material also showed a mosaicity and a defect density similar to those of the substrate. It can be expected that the protective effect of these coatings against oxidation is greatly enhanced compared with polycrystalline coatings because high diffusivity paths, such as grain boundaries, are eliminated in single-crystalline coatings, thus reducing mass transport through the coating.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Acta Materialia - Volume 57, Issue 18, October 2009, Pages 5292–5302
نویسندگان
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