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1.
Under carefully chosen conditions, solidification theory may be applied to solid-state transformations, and this has been
done here for composition-invariant diffusion transformations. The predictions of the modeling are compared with isovelocity
experiments in two iron systems, Fe-7.29 wt pct Cr and Fe-3.1 wt pct Ni. The ferrite to austenite phase transformation is
used to demonstrate that stabilization of a planar transformation front at absolute stability is the natural lower velocity
limit for a composition-invariant (massive) transformation. The results of the model, which includes nonequilibrium effects,
clearly show that steady-state plane-front growth leading to composition invariance can be obtained at various temperatures
depending on the growth velocity. In the lower velocity range, at the limit of absolute stability (of the order of 10 μm/s in the systems studied), the transformation interface moves under conditions of local equilibrium, and the temperature
corresponds to the lower solvus temperature. At higher velocity (of the order of the interface diffusion rate, which in these
systems is of the order of cm/s), the transformation is predicted to proceed at temperatures close to T
0. At even higher rates, atom attachment kinetic undercooling will decrease the transformation temperature with respect to
T
0. In some cases, this temperature might even drop below the lower solvus.
This article is based on a presentation made at the symposium entitled “The Mechanisms of the Massive Transformation,” a part
of the Fall 2000 TMS Meeting held October 16–19, 2000, in St. Louis, Missouri, under the auspices of the ASM Phase Transformations
Committee. 相似文献
2.
Ohne Zusammenfassung 相似文献
3.
Additional remarks are given for the data of auroras during the earlier centuries. 相似文献
4.
Wilfried Reiners 《Datenschutz und Datensicherheit - DuD》2006,30(11):720-720
5.
6.
A numerical model based on the finite-element method for solving the nonlinear diffusion equation of ion-exchange in glasses is presented. The model is applied to the calculation of the concentration profile for a Ag+-Na+ ion-exchanged channel waveguide. The calculated concentration profile is in good agreement with a measured refractive-index profile of a waveguide fabricated with the same parameters as used in the calculations 相似文献
7.
Translated the MMPI into American Sign Language (ASL) via the back-translation procedure and recorded it on videotape to determine the linguistic equivalency of a sign language translation of a psychological test for use with deaf individuals. The bilingual retest technique was conducted whereby both forms of the instrument were administered to 28 ASL-English bilingual deaf Ss. Due to the advent of the MMPI-2 during the conduct of this study, a new set of T scores was calculated from the present MMPI data to compare the effect of shifting to the MMPI-2 norms. The results demonstrate adequate linguistic equivalencies of the ASL MMPI items and underscore the potential utility and practicality of future ASL translations of psychological tests for use with deaf individuals. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
B. S. Seplyarskii S. V. Kostin G. B. Brauer 《International Journal of Self-Propagating High-Temperature Synthesis》2008,17(2):121-124
Explored is the filtration combustion in Ti-(Ti + 0.5C) layered powder systems in a coflow of nitrogen gas. The presence/absence
of nitrogen coflow through the layered system was found to drastically affect the character of wave propagation and structure/properties
of product. The obtained data can be regarded as a basis for fabrication of new layered and composite materials in the mode
of dynamic filtration combustion.
相似文献
9.
Besides equidistribution properties and statistical independence the lattice profile, a generalized version of Marsaglia's
lattice test, provides another quality measure for pseudorandom sequences over a (finite) field. It turned out that the lattice
profile is closely related with the linear complexity profile. In this article we give a survey of several features of the
linear complexity profile and the lattice profile, and we utilize relationships to completely describe the lattice profile
of a sequence over a finite field in terms of the continued fraction expansion of its generating function. Finally we describe
and construct sequences with a certain lattice profile, and introduce a further complexity measure. 相似文献
10.