کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1604977 1516204 2017 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Influence of γ′ precipitates on the critical strain and localized deformation of serrated flow in Ni-based superalloys
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد فلزات و آلیاژها
پیش نمایش صفحه اول مقاله
Influence of γ′ precipitates on the critical strain and localized deformation of serrated flow in Ni-based superalloys
چکیده انگلیسی
Although γ′ precipitates enhance the strength of Ni-based superalloys, they can also promote an undesirable phenomenon called the Portevin-Le Chatelier (PLC) effect. Alloys designed and fabricated with various γ′ contents were subjected to uniaxial tensile tests at different temperatures (523-923 K) and strain rates (1 × 10−4-3 × 10−3 s−1). It was found that the γ′ precipitates facilitated a transition of the PLC effect from normal to inverse behavior. From the viewpoint of the critical strain, the temperature transition region shifted to low temperatures with increasing γ′ content. Digital image correlation was applied to the observations of the localization band in relation to the γ′ content at 773 K and 1 × 10−4 s−1. Surface strain mapping indicated that severe localized deformation was accompanied by high-amplitude serrations. Microscopic observations from transmission electron microscopy indicated that the deformation mode switched from dislocation motion to stacking fault (SF) formation with increasing γ′ content. With the aid of Suzuki segregation and SF intersections of different slip planes, a large number of SFs might induce high-amplitude serrations, especially those associated with the inverse PLC effect.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Alloys and Compounds - Volume 690, 5 January 2017, Pages 707-715
نویسندگان
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