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Grain boundary migration initiated by diffusion
Russian Physics Journal, 1992A review is presented of work related to two new processes which arise in crystalline materials when impurities diffuse along grain boundaries from the surface of the material: diffusion-initiated grain boundary migration and recrystallization. We analyze the conditions under which DIGM occurs, the kinetics of the process, its driving forces, and also ...
A. D. Korotaev, Yu. I. Pochivalov
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Kinetics of Initial Sintering with Grain Growth
Journal of the American Ceramic Society, 1970Kinetic equations for initial sintering were obtained by combining the conventional kinetic equation with an empirical expression for grain growth in the initial stage. The equations describe the isothermal shrinkage of ZnO in O 2 at 80 torr and 800° to 950°C.
YUSUKE MORIYOSHI, WAZO KOMATSU
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Thermal Relaxation of Initially Fractal Grain Boundaries
Fractals, 1997The concept of fractal geometry is used to describe serrated and rugged grain boundaries in the pure materials Zinc and Titanium after deformation and heat treatment. The fractal dimension of the grain boundaries are determined by application of optical and scanning electron microscopy over a wide range of magnifications.
P. Streitenberger, D. Förster, P. Veit
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On the stability of grain structure with initial Weibull grain size distribution
Materials Letters, 2003A microstructure with a Weilbull grain size distribution (GSD) was generated and subjected to normal grain growth (NGG) by the Monte Carlo Potts method. The results show that the GSD keeps almost invariant during NGG. The Weibull function fits well the steady-state GSDs evolving from the Weibull and the Hillert distributions.
Chao Wang, Guoquan Liu
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Effect of initial grain size on the secondary grain growth in molybdenum sheet
Materials Science and Engineering, 1984Abstract In order to understand in more detail the secondary recrystallization behaviour of rolled molybdenum sheet doped with CaO and MgO, the effect of initial grain size on the secondary grain growth behaviour was investigated using optical microscopy and X-ray diffraction.
Tadayuki Fujii +3 more
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Initiation of motion of quartz sand grains
1991Direct observation at a limited range of wind speeds of grain behaviour near the upwind edge of a sand deposit (by means of high-speed film) shows that disturbed grains usually, but not always, roll before taking off into reptation or saltation. Time-averaged description of the population of initial motions is deficient because of the importance of ...
B. B. Willetts, I. K. McEwan, M. A. Rice
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Effect of initial grain size on sintering trajectories
Acta Materialia, 2000Sintering trajectories were simulated for different initial grain sizes assuming grain-boundary diffusion as densification mechanism and either pore drag or intrinsic grain-boundary mobility as grain growth mechanisms. Computation of comparable sintering trajectories for initial grain sizes between 10 nm and 250 nm necessitated an adjustment of the ...
J. Kanters, U. Eisele, J. Rödel
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Temperature induced smoothing of initially fractal grain boundaries
Scripta Materialia, 1996Recently the effect of serrated or rugged grain boundaries on the mechanical properties of alloys and the numerical characterization of such a geometrically irregular microstructure by means of the concept of fractal geometry has attracted great attention. It has been reported that the generation of serrated or rugged grain boundaries, e.g.
P. Streitenberger +3 more
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Grain size ratio may be crucial for the fluid initiation of martian sand grains
Icarus, 2021Abstract The active Aeolian sand movement on the Martian surface has been puzzling scientists for several decades because the existing theories do not support the initiation of sand grains under the current Martian environment. In this study, I theoretically calculated the fluid threshold (u⁎ft) for the initiation of sand grain movement by ...
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