کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5455602 1514639 2017 21 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
New insights into the mechanism of cooling rate on the impact toughness of coarse grained heat affected zone from the aspect of variant selection
ترجمه فارسی عنوان
بینش های جدید در مورد مکانیزم نرخ خنک کننده بر شدت ضربه ناشی از ناحیه آسیب دیده درشت دانه درشت از جنبه انتخاب نوع
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد دانش مواد (عمومی)
چکیده انگلیسی
In this article, the authors tried to establish a direct correlation between crystallographic variants and impact toughness, and provided some novel insights into the mechanism of cooling rate on the impact toughness of coarse grained heat affected zone (CGHAZ) of offshore engineering steel by means of electron back-scattering diffraction (EBSD) analysis. The results showed that variant selection becomes stronger with an decrease in the cooling rate, resulting in the decline of high angle grain boundaries (HAGBs) and thus lower the impact toughness. Moreover, the variation in impact toughness is mainly correlated to the crystallographic block size. The larger the block size, the lower the impact toughness. By visualizing the crystallographic features, it has been clarified that the transition from Bain zone grouping to close-packed plane grouping with the increase of cooling rate, while the corresponding microstructure changes from granular bainite to lath bainite. Furthermore, it has been found that ~ 25% (number fraction) reconstructed prior austenite grains in simulated CGHAZ present a twin-related structure (austenitic twin), which can enhance the variant selection and displays a negative effect on the formation of HAGBs.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Materials Science and Engineering: A - Volume 704, 17 September 2017, Pages 448-458
نویسندگان
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