کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
7979157 1514719 2015 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Excellent superplasticity and deformation mechanism of Al-Mg-Sc-Zr alloy processed via simple free forging
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد دانش مواد (عمومی)
پیش نمایش صفحه اول مقاله
Excellent superplasticity and deformation mechanism of Al-Mg-Sc-Zr alloy processed via simple free forging
چکیده انگلیسی
A refined microstructure of Al-Mg-Sc-Zr alloy with an average grain size of ~3.7 μm and a portion of high angle boundaries of 69.2% was produced by free forging. Excellent superplastic ductility of ≥500% was achieved at a wide temperature range of 450~500 °C and relatively high strain rate range of 1×10−3~5×10−2 s−1 in the Al-Mg-Sc-Zr alloy. A maximum elongation of 1593% was obtained at 475 °C and 1×10−3 s−1. Moreover, the electron back scattered diffraction (EBSD) and the transmission electron microscopy (TEM) analyses showed that the excellent superplasticity can be attributed to the high fraction of high angle grain boundaries and the presence of Al3(Sc,Zr) dispersoids in the Al-Mg-Sc-Zr alloy microstructure. The analyses on the superplastic data revealed the presence of threshold stress, the coefficient of strain rate sensitivity of 0.5, and an activation energy of 83.9 kJ/mol-1. It indicated that the dominant deformation mechanism was grain boundary sliding. Based on this notion, a constitutive equation for Al-Mg-Sc-Zr alloy has been developed.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Materials Science and Engineering: A - Volume 624, 29 January 2015, Pages 124-131
نویسندگان
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