Phase transformation and grain growth behavior of a nanocrystalline 18/8 stainless steel
Küçük Resim Yok
Tarih
2017
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Elsevier Science Sa
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
Fe-18Cr-8Ni and Fe-18Cr-8Ni-1Y (at%) stainless steel powders were nanostructured by mechanical alloying from elemental powders and subjected to 90 min annealing treatments at various temperatures. The microstructural evolutions as a function of alloy compositions and temperatures were investigated by in-situ and ex-situ x-ray diffraction experiments, transmission electron microscopy and focused ion beam microscopy. The dependence of hardness on the microstructure was utilized to study the mechanical changes. It was found that the resulting microstructures by mechanical alloying were bcc solid solution, the so-called alpha'-martensite structure. The high temperature in-situ x-ray diffraction experiments showed that the martensite-to-austenite reverse phase transformation was completed above 800 and 900 degrees C for Fe-18Cr-8Ni and Fe-18Cr-8Ni-1Y steels, respectively. A partial or complete retransformation to martensite was observed upon cooling to room temperature. Annealing of nanocrystalline Fe-18Cr-8Ni steel yielded grain growth reaching to micron sizes at 1100 degrees C while addition of 1 at% yttrium stabilized the microstructure around 160 nm grain size and 6 GPa hardness after 90 min annealing at 1200 degrees C.
Açıklama
Anahtar Kelimeler
Stainless Steels, Martensitic Transformation, Grain Growth, Phase Transformation, High Temperature X-Ray Diffraction, Metastable Austenite
Kaynak
Materials Science And Engineering A-Structural Materials Properties Microstructure And Processing
WoS Q Değeri
Q1
Scopus Q Değeri
Q1
Cilt
686
