Microstructural evolution of 316L stainless steels with yttrium addition after mechanical milling and heat treatment
Küçük Resim Yok
Tarih
2015
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Elsevier Science Sa
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
Nanocrystalline 316L stainless steels with yttrium addition were prepared by mechanical milling at cryogenic temperature and subjected to annealing treatments at various temperatures up to 1200 degrees C. The dependence of hardness on the microstructure was utilized to study the mechanical changes in the steels occurring during annealing. The microstructural evolution of the as-milled and annealed steels was characterized by means of X-ray diffraction (XRD), focused ion beam microscopy (FIB) and transmission electron microscopy (TEM) techniques. The results have revealed that austenite in as-received powder partially transformed to martensite phase during mechanical milling whereas the annealing induced reverse transformation of martensite-to-austenite. Furthermore, while the austenite-to-martensite phase ratio increased with increasing annealing temperature, the equilibrium structure was not achieved after three hours heat treatments up to 1200 degrees C resulting in a dual-phased steels with around 10% martensite. The grain size of 316L steel was 19 nm after mechanical milling and remained around 116 nm at 1100 degrees C with yttrium addition as opposed to micron size grains of plain 316L steel at the same annealing temperature. Such microstructural features facilitate the use of these materials at elevated temperatures, as well as the development of scalable processing routes into a dense nanocrystalline compact. (C) 2015 Elsevier B.V. All rights reserved.
Açıklama
Anahtar Kelimeler
Mechanical Milling, Grain Refinement, Nanocrystalline Steels, Grain Growth, Thermal Stability, Martensitic Transformation
Kaynak
Materials Science And Engineering A-Structural Materials Properties Microstructure And Processing
WoS Q Değeri
Q1
Scopus Q Değeri
Q1
Cilt
647
