Journal ArticleDOI
Phase transformations and phase stability in nanocrystalline materials
TLDR
In this paper, a review of the current state of the researches on diffusionless phase transformations, including allotropic, polymorphous and martensitic transformations, and phase stability are reviewed.Abstract:
The current state of the researches on diffusionless phase transformations, including allotropic, polymorphous and martensitic transformations, and phase stability are reviewed. The behaviors of phase transformation and phase stability in nanocrystalline materials are markedly affected by the non-equilibrium conditions involved in their preparation, as a result, in this review an ideal demonstrating method of critical size for the stability of a high-temperature phase at low-temperatures is suggested, and the intrinsic conditions of the phase stability are clarified. Our recent experiments exhibit that the reversal transformation temperatures of low-temperature phases in nanocrystalline Co bulk metal and Fe–30Ni wt% alloy are significantly raised up over 800 °C when their grain sizes are smaller than about 15 nm, while in the reported experiments of nanocrystalline particles or films the reversal transformation temperature lowers with decreasing grain size or is independent of grain size. Therefore, the author suggests that more experiments and theories for phase stability in reversal transformation should be performed. The study of grain growth kinetics of nanocrystalline materials, as a basic of investigating phase stability, is another attention aspect.read more
Citations
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Journal ArticleDOI
Microstructures and properties of high-entropy alloy films and coatings: a review
Wei Li,Ping Liu,Peter K. Liaw +2 more
TL;DR: In the past 14 years, as a branch of high-entropy alloy (HEA) materials, HEA films and coatings have exhibited the attractive and unique properties, relative to the conventional film and coating ma...
Journal ArticleDOI
Dependence of martensite start temperature on fine austenite grain size
TL;DR: In this article, the authors examined the validity of existing neural network models, but focusing on fine AGS (below 5μm) and showed that such models predict a moderate dependence of M s with AGS.
Book
Handbook of Gas Sensor Materials: Properties, Advantages and Shortcomings for Applications Volume 2: New Trends and Technologies
TL;DR: The Handbook of Gas Sensor Materials : Properties, Advantages and Shortcomings for Applications Volume 2: New Trends and Technologies as mentioned in this paper is available on our book collections and it comes PDF and EPUB document format.
Journal ArticleDOI
The role of grain size on the thermal instability of nanostructured metal oxides used in gas sensor applications and approaches for grain-size stabilization
Ghenadii Korotcenkov,Beongki Cho +1 more
TL;DR: In this paper, the influence of grain size on the thermal stability of nanostructured metal oxides by studying their structural parameters was examined and the effectiveness of different approaches used for stability improvement of metal-oxide structures were considered.
Journal ArticleDOI
Measurement of microstructural parameters of nanocrystalline Fe–30 wt.%Ni alloy produced by surface mechanical attrition treatment
TL;DR: In this article, X-ray diffraction line profile analysis (XLPA) and transmission electron microscopy (TEM) were used to measure the average crystallite size, root mean square microstrain, dislocation density and stored elastic energy.
References
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Journal ArticleDOI
Nanostructured materials: basic concepts and microstructure☆
TL;DR: In this article, the authors summarize the basic physical concepts and the microstructural features of equilibrium and non-equilibrium nanostructured materials (NsM) and make an attempt to summarize their properties.
Journal ArticleDOI
Nanostructured surface layer on metallic materials induced by surface mechanical attrition treatment
TL;DR: In this article, a surface mechanical attrition treatment (SMAT) was developed for synthesizing a nanostructured surface layer on metallic materials in order to upgrade the overall properties and performance.
Journal ArticleDOI
Alloy effects in nanostructures
TL;DR: In this paper, the grain boundary specific energy is reduced by grain boundary segregation, and a narrowing of the glass-forming region is predicted when the metastable polycrystal can form.
Journal Article
Surface Nanocrystallization (SNC) of Metallic Materials-Presentation of the Concept behind a New Approach
Journal ArticleDOI
Size effect on the crystal phase of cobalt fine particles
TL;DR: In this paper, the size dependence of the crystal phase of the Co fine particles was investigated, and it was shown that the stabilization of crystal phase is the intrinsic effect caused by the small dimensionality of fine particles.