کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5460042 1516190 2017 24 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Effects of homogenization treatments on the microstructure evolution, microhardness and electrical conductivity of dilute Al-Sc-Zr-Er alloys
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد فلزات و آلیاژها
پیش نمایش صفحه اول مقاله
Effects of homogenization treatments on the microstructure evolution, microhardness and electrical conductivity of dilute Al-Sc-Zr-Er alloys
چکیده انگلیسی
The effects of homogenization treatments on the microstructure evolution, microhardness and electrical conductivity of two dilute Al-Sc-Zr-Er alloys with different Zr contents were investigated. In both as-cast alloy, Zr and Sc are respectively concentrated at the dendrite interiors and the interdendritic regions, and Er is segregated at the primary Al3Er phases within grain and discontinuous intergranular phases with traces of Sc and Fe. The severe microsegregation of Zr induces the formation of the coarse Zr-rich precipitates in the high Zr alloy during homogenization. The composition of the coarse phase is analyzed by EPMA and STEM-HAADF and a corresponding model of its formation mechanism is proposed. The optimal homogenization duration of the both studied alloys depends on the segregation degree of Zr in the dendritic cells. For the high Zr alloy, the homogenization for 2 h at 640 °C eliminates the primary Al3Er phases and the intergranular Er/Sc-rich phases without the coarse Al3(Er,Sc,Zr) phases. For the low high Zr alloy, 24 h of homogenization at 640 °C eliminates successfully the microsegregation of Zr, Sc and Er, and induces the maximum aging strengthening increment.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Alloys and Compounds - Volume 704, 15 May 2017, Pages 683-692
نویسندگان
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