کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
9952570 | 1454933 | 2018 | 28 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Stratified surface layers on rails
ترجمه فارسی عنوان
لایه سطحی طبقه بندی شده روی ریل
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
مهندسی شیمی
شیمی کلوئیدی و سطحی
چکیده انگلیسی
This study examines the properties of stratified surface layers on rails in service and presents a hypothesis explaining their origin. The stratified layer consists of a white etching top layer and a brown sublayer. The metallurgical composition and properties of this sublayer are found to match with that of globular bainite. The occurrence of stratification in the surface layer is explained by the thermomechanical cycle for a material point on the rail surface under wheel-rail contact. Difference in the surface and subsurface cooling rates after reaching the austenitisation temperature may lead, depending on the chemical steel composition, to the generation of two different phases (martensite and bainite) and stratification. The exclusive occurrence of sandwich layers on rails that have been in service is attributed to the hardening of the top layer, leading to a reduced thermal conductivity, which gains relevance at an increasing depth. The granular morphology of the bainitic sublayer, exhibiting weak globular inclusions, facilitates the initiation and the propagation of transverse cracks, thus contributing to the development of RCF.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Wear - Volumes 414â415, 15 November 2018, Pages 151-162
Journal: Wear - Volumes 414â415, 15 November 2018, Pages 151-162
نویسندگان
Maha Messaadi, Michaël Steenbergen,