کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
8044054 1518915 2018 17 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Influence of phase transformation on the damage tolerance of Ti-Al-N coatings
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد سطوح، پوشش‌ها و فیلم‌ها
پیش نمایش صفحه اول مقاله
Influence of phase transformation on the damage tolerance of Ti-Al-N coatings
چکیده انگلیسی
In contrast to earlier work, where we focused on the evolution of fracture toughness upon annealing of free-standing Ti-Al-N films using cantilever bending experiments, here we study the practically more relevant case of thin Ti-Al-N films firmly attached to a stiff substrate. We found - experimentally and by continuum mechanics modelling using the Transformation Field Analysis - that the formation of even tiny fractions of hcp (ZnS-wurtzite type) AlN during decomposition of supersaturated fcc (NaCl-type) Ti-Al-N gives rise to high in-plane compressive stresses in both the matrix and the precipitates. These eigenstresses impede the formation and propagation of cracks as evidenced by cube corner nanoindentation experiments - the measured fracture toughness (KIC) increases from the as-deposited value of ∼4.4 MPa√m to ∼8.0 MPa√m when annealed at 900 °C. The (apparent) toughening effects combine with less pronounced inherent toughening and concomitant age hardening effects to enhanced damage tolerance of annealed Ti-Al-N.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Vacuum - Volume 155, September 2018, Pages 153-157
نویسندگان
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