scholarly journals Time-dependent interface stability during directional solidification of a single phase alloy(Ⅰ) Theoritical

2004 ◽  
Vol 53 (11) ◽  
pp. 3971
Author(s):  
Lin Xin ◽  
Li Tao ◽  
Wang Lin-Lin ◽  
Su Yun-Peng ◽  
Huang Wei-Dong
Keyword(s):  
Directional Solidification ◽  
Single Phase ◽  
Time Dependent ◽  
Interface Stability ◽  
Single Phase Alloy

A multi-scale analysis of the residual stresses developed in a single-phase alloy cylinder after quenching

2018 ◽  
Vol 137 ◽  
pp. 117-127 ◽  
Author(s):  
R. Fernández ◽  
S. Ferreira-Barragáns ◽  
J. Ibáñez ◽  
G. González-Doncel
Keyword(s):  
Residual Stresses ◽  
Single Phase ◽  
Scale Analysis ◽  
Single Phase Alloy ◽  
Multi Scale ◽  
Multi Scale Analysis

A MATHEMATICAL ANALYSIS OF SOLUTE REDISTRIBUTION DURING SOLIDIFICATION

1955 ◽  
Vol 33 (12) ◽  
pp. 723-745 ◽  
Author(s):  
V. G. Smith ◽  
W. A. Tiller ◽  
J. W. Rutter
Keyword(s):  
Steady State ◽  
Mathematical Analysis ◽  
Single Phase ◽  
Solute Concentration ◽  
Solute Redistribution ◽  
Single Phase Alloy

A mathematical analysis is made of the redistribution of solute which occurs during the solidification, without convection, of a single-phase alloy. Calculations of solute distributions are carried out for steady state conditions, and for the transient changes in solute concentration, both in the solid and in the liquid, which occur at the beginning and end of solidification and as a result of a change in the speed of solidification. The solute distributions in the transient regions are considered for the case of two solutes present in the melt. It is shown that, under certain conditions, p–n junctions may be produced in the transient regions of solidification in germanium or silicon melts containing two suitable solutes.

Filter-Based Unsteady RANS Computations for Single-Phase and Cavitating Flows

Volume 3 ◽  
2004 ◽  
Author(s):  
Jiongyang Wu ◽  
Wei Shyy ◽  
Stein T. Johansen
Keyword(s):  
Eddy Viscosity ◽  
Single Phase ◽  
Experimental Information ◽  
Time Dependent ◽  
Navier Stokes ◽  
Cavitating Flows ◽  
Two Phase ◽  
Navier Stokes Equation ◽  
Filter Size ◽  
The Impact

The widely used Reynolds-Averaged Navier-Stokes (RANS) approach, such as the k-ε two-equation model, has been found to over-predict the eddy viscosity and can dampen out the time dependent fluid dynamics in both single- and two-phase flows. To improve the predictive capability of this type of engineering turbulence closures, a consistent method is offered to bridge the gap between DNS, LES and RANS models. Based on the filter size, conditional averaging is adopted for the Navier-Stokes equation to introduce one more parameter into the definition of the eddy viscosity. Both time-dependent single-phase and cavitating flows are simulated by a pressure-based method and finite volume approach in the framework of the Favre-averaged equations coupled with the new turbulence model. The impact of the filter-based concept, including the filter size and grid dependencies, is investigated using the standard k-ε model and with the available experimental information.

Effect of Nb on Magnetic Properties, Microstructures, and Site Preference in Nd-Fe-B Nanograin Single-Phase Alloy

2016 ◽  
Vol 29 (10) ◽  
pp. 2591-2597 ◽  
Author(s):  
Fang Yang ◽  
Lei-chen Guo ◽  
Guang-le Dong ◽  
Yan-li Sui ◽  
Ping Qian ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Single Phase ◽  
Site Preference ◽  
Single Phase Alloy

X-Ray Dynamical Diffraction in Powder Samples with Time-Dependent Particle Size Distributions

MRS Advances ◽  
2019 ◽  
Vol 5 (29-30) ◽  
pp. 1585-1591 ◽  
Author(s):  
Adriana Valério ◽  
Sérgio L. Morelhão ◽  
Alex J. Freitas Cabral ◽  
Márcio M. Soares ◽  
Cláudio M. R. Remédios
Keyword(s):  
Particle Size ◽  
Single Phase ◽  
Diffraction Peak ◽  
Time Dependent ◽  
Peak Width ◽  
Dynamical Diffraction ◽  
X Ray ◽  
Integrated Intensity ◽  
Diffraction Effects

ABSTRACTIn situ X-ray diffraction is one of the most useful tools for studying a variety of processes, among which crystallization of nanoparticles where phase purity and size control are desired. Growth kinetics of a single phase can be completely resolved by proper analysis of the diffraction peaks as a function of time. The peak width provides a parameter for monitoring the time evolution of the particle size distribution (PSD), while the peak area (integrated intensity) is directly related to the whole diffracting volume of crystallized material in the sample. However, to precisely describe the growth kinetics in terms of nucleation and coarsening, the correlation between PSD parameters and diffraction peak widths has to be established in each particular study. Corrections in integrated intensity values for physical phenomena such as variation in atomic thermal vibrations and dynamical diffraction effects have also to be considered in certain cases. In this work, a general correlation between PSD median value and diffraction peak width is deduced, and a systematic procedure to resolve time-dependent lognormal PSDs from in situ XRD experiments is described in details. A procedure to correct the integrated intensities for dynamical diffraction effects is proposed. As a practical demonstration, this analytical procedure has been applied to the single-phase crystallization process of bismuth ferrite nanoparticles.

Sign in / Sign up

Export Citation Format

Share Document