Journal ArticleDOI
A quantitative demonstration of the grain boundary diffusion mechanism for the oxidation of metals
TLDR
In this article, the authors report measurements of the oxide scale thickness and oxide grain size as a function of time during the oxidation of high-purity nickel in the temperature range 500-800°C.Abstract:
Below 1000°C the oxidation of nickel cannot be controlled by the diffusion of ions through the bulk crystal lattice of the pure oxide, because the measured oxidation rates are several orders of magnitude faster than would be predicted on this basis. Short-circuit diffusion through oxide grain boundaries or dislocations has usually been held responsible, but there has hitherto been no proper quantitative confirmation of this mechanism. We report measurements of the oxide scale thickness and oxide grain size as a function of time during the oxidation of high-purity nickel in the temperature range 500–800°C. All the oxidation experiments were carried out in pure oxygen at a pressure of one atmosphere. The measured parabolic oxidation rate constants have been compared with those calculated from grain boundary diffusion data obtained in our previous work, using a grain boundary diffusion model for the oxidation process. The quantitative agreement between measured and calculated oxidation rates shows c...read more
Citations
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Journal ArticleDOI
Oxidation Mechanism of Steels in Liquid–Lead Alloys
Jinsuo Zhang,N. Li +1 more
TL;DR: In this paper, a model of the oxidation mechanism of steels in liquid-lead alloys (lead or lead-bismuth) was developed based on the assumptions that the chemical reactions are at equilibrium locally, and scale removal is due to mass-transfer corrosion.
Journal ArticleDOI
Wagner theory and short circuit diffusion
TL;DR: In this article, the expected relationship between growth rate and diffusion constants is not generally confirmed experimentally and usually the oxidation rate is many orders of magnitude greater than expected, and when this is taken into account the oxidation rates and diffusion data can be reconciled.
Journal ArticleDOI
Effects of Al on the microstructure and ductility of NiAl-strengthened ferritic steels at room temperature
TL;DR: In this paper, the effect of Al content on the ductility of prototype Fe-Ni-Cr-Al alloys was investigated, and it was shown that NiAl-type precipitates exhibit poor ductility and their fracture mode is predominantly cleavage type.
Journal ArticleDOI
Structural, electronic, mechanical and thermodynamic properties of Cr–Si binary silicides from first-principles investigations
TL;DR: In this paper, the structural, mechanical, electronic and thermodynamic properties of Cr-Si binary silicides are investigated and one novel Cr2Si orthorhombic structure (Pnma) is predicted.
Journal ArticleDOI
Structural, mechanical, and electronic properties of P3m1-BCN
Qingyang Fan,Qun Wei,Changchun Chai,Haiyan Yan,Meiguang Zhang,Zheng-Zhe Lin,Zixia Zhang,Junqin Zhang,Dongyun Zhang +8 more
TL;DR: In this article, the mechanical and electronic properties of P3m1-BCN have been studied by using first principles calculations, and the anisotropy studies of Young's modulus, shear modulus and Poisson's ratio have been performed.
References
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Journal ArticleDOI
Beitrag zur Theorie des Anlaufvorgangs
TL;DR: The Mechanismus des Diffusionsvorgangs is still weitgehend unbekannt as discussed by the authors, i.e., the Diffusion of mindestens einem der beiden Bestandteile durch die Anlaufschicht is notwendig.
Journal ArticleDOI
The diffusion of 63Ni along grain boundaries in nickel oxide
A. Atkinson,R. I. Taylor +1 more
TL;DR: The product of the grain boundary diffusion coefficient and width, D′δ, has been measured directly for the diffusion of 63Ni along grain boundaries in high-purity NiO as discussed by the authors.
Journal ArticleDOI
The role of oxide microstructure and growth stresses in the high-temperature scaling of nickel
F. N. Rhines,J. S. Wolf +1 more
TL;DR: In this article, the formation of new nickel oxide upon boundaries of columnar grains where nickel diffusing through the oxide crystals, meets oxygen, diffusing along grain boundaries is identified as the primary cause of this stress.
Journal ArticleDOI
The diffusion of Ni in the bulk and along dislocations in NiO single crystals
A. Atkinson,R. I. Taylor +1 more
TL;DR: In this paper, diffusion profiles of 63Ni tracer in single crystals of NiO following anneals at 522°-1000°C have been determined by a radio-frequency sputter-sectioning technique.
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