کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1449894 988717 2007 12 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Compositional pathways and capillary effects during isothermal precipitation in a nondilute Ni–Al–Cr alloy
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد سرامیک و کامپوزیت
پیش نمایش صفحه اول مقاله
Compositional pathways and capillary effects during isothermal precipitation in a nondilute Ni–Al–Cr alloy
چکیده انگلیسی

For a Ni–5.2Al–14.2Cr at.% alloy with moderate solute supersaturations, the compositional pathways, as measured with atom-probe tomography, during early to later stage γ′(L12)-precipitation (R = 0.45–10 nm), aged at 873 K, are discussed in light of a multi-component coarsening model. Employing nondilute thermodynamics, detailed model analyses during quasi-stationary coarsening of the experimental data establish that the γ/γ′ interfacial free-energy is 22–23 ± 7 mJ m−2. Additionally, solute diffusivities are significantly slower than model estimates. Strong quantitative evidence indicates that an observed γ′-supersaturation of Al results from the Gibbs–Thomson effect, providing the first experimental verification of this phenomenon. The Gibbs–Thomson relationship for a ternary system, as well as differences in measured phase equilibria with CALPHAD assessments, are considered in great detail.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Acta Materialia - Volume 55, Issue 1, January 2007, Pages 119–130
نویسندگان
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