Influence of Nucleation Mechanisms on the Multiplicity Patterns of Agglomeration-Controlled Crystallization

2001 ◽  
Vol 40 (26) ◽  
pp. 6221-6227 ◽  
Author(s):  
Qiuxiang Yin ◽  
Jingkang Wang ◽  
Meijing Zhang ◽  
Yongli Wang
Keyword(s):  
Nucleation Mechanisms ◽  
Controlled Crystallization ◽  
Multiplicity Patterns

Exsolution and inversion in pigeonite from the Whin Sill, Northern England

1978 ◽  
Vol 36 (1) ◽  
pp. 474-475
Author(s):  
P.P.K. Smith
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Homogeneous Nucleation ◽  
Silicate Mineral ◽  
Antiphase Boundaries ◽  
Two Phase ◽  
Primitive Form ◽  
The Core ◽  
Nucleation Mechanisms ◽  
And Inversion

Grains of pigeonite, a calcium-poor silicate mineral of the pyroxene group, from the Whin Sill dolerite have been ion-thinned and examined by TEM. The pigeonite is strongly zoned chemically from the composition Wo8En64FS28 in the core to Wo13En34FS53 at the rim. Two phase transformations have occurred during the cooling of this pigeonite:- exsolution of augite, a more calcic pyroxene, and inversion of the pigeonite from the high- temperature C face-centred form to the low-temperature primitive form, with the formation of antiphase boundaries (APB's). Different sequences of these exsolution and inversion reactions, together with different nucleation mechanisms of the augite, have created three distinct microstructures depending on the position in the grain.In the core of the grains small platelets of augite about 0.02μm thick have farmed parallel to the (001) plane (Fig. 1). These are thought to have exsolved by homogeneous nucleation. Subsequently the inversion of the pigeonite has led to the creation of APB's.

Computerized simulation of shortened ingots with a controlled crystallization for manufacturing of high-quality forgings

2019 ◽  
Vol 103 (5-8) ◽  
pp. 3057-3065 ◽  
Author(s):  
Oleg E. Markov ◽  
Oleksiy V. Gerasimenko ◽  
Alexander A. Shapoval ◽  
Oleksandr R. Abdulov ◽  
Roman U. Zhytnikov
Keyword(s):  
High Quality ◽  
Controlled Crystallization ◽  
Computerized Simulation

scholarly journals How volatile components catalyze vapor nucleation

2021 ◽  
Vol 7 (3) ◽  
pp. eabd9954 ◽  
Author(s):  
Chenxi Li ◽  
Jan Krohn ◽  
Martina Lippe ◽  
Ruth Signorell
Keyword(s):  
Gas Phase ◽  
Molecular Level ◽  
Volatile Components ◽  
Transient Species ◽  
Gaseous Species ◽  
Alternative Pathways ◽  
Nucleation Mechanisms ◽  
Designed Experiment ◽  
Phase Nucleation ◽  
Vapor Nucleation

Gas phase nucleation is a ubiquitous phenomenon in planetary atmospheres and technical processes, yet our understanding of it is far from complete. In particular, the enhancement of nucleation by the addition of a more volatile, weakly interacting gaseous species to a nucleating vapor has escaped molecular-level experimental investigation. Here, we use a specially designed experiment to directly measure the chemical composition and the concentration of nucleating clusters in various binary CO2-containing vapors. Our analysis suggests that CO2 essentially catalyzes nucleation of the low vapor pressure component through the formation of transient, hetero-molecular clusters and thus provides alternative pathways for nucleation to proceed more efficiently. This work opens up new avenues for the quantitative assessment of nucleation mechanisms involving transient species in multicomponent vapors.

Well-defined micropatterns of polymers prepared by controlled crystallization process

2009 ◽  
Vol 4 (4) ◽  
pp. 383-389 ◽  
Author(s):  
Jijun Wang ◽  
Yinjie Sun ◽  
Yun Huang ◽  
Erqiang Chen ◽  
Huihui Li ◽  
...  
Keyword(s):  
Crystallization Process ◽  
Controlled Crystallization

Polyethylene-CaCO3 hybrid via CaCO3 -controlled crystallization in emulsion

2011 ◽  
Vol 49 (5) ◽  
pp. 1289-1292
Author(s):  
Stanislaw Penczek ◽  
Krzysztof Kaluzynski ◽  
Julia Pretula
Keyword(s):  
Controlled Crystallization

Physical Based Microstructure Modelling Coupled with Nucleation Theory during and after Hot Forming of AA5083

2010 ◽  
Vol 89-91 ◽  
pp. 509-514
Author(s):  
Pavel Sherstnev ◽  
Christof Sommitsch ◽  
Stefan Mitsche ◽  
Carsten Melzer
Keyword(s):  
Aluminium Alloy ◽  
Hot Rolling ◽  
Volume Fraction ◽  
Electron Backscatter Diffraction ◽  
Grain Structure ◽  
Nucleation Theory ◽  
Structure Evolution ◽  
Nucleation Sites ◽  
Nucleation Mechanisms ◽  
Backscatter Diffraction

A physical model based on three types of dislocations and three nucleation sites for recrystallized grain is applied to hot rolling simulation. This model was implemented into a commercial Finite Element (FE) analysis package FORGE 2008 to calculate both the structure evolution during and the recrystallized volume fraction after hot working of aluminium alloy 5083. It is shown that the main nucleation mechanisms in the aluminium alloy are the particle stimulated nucleation (PSN) and nucleation at grain boundaries. Hence the precipitation kinetics during homogenisation was investigated by use of the thermodynamic calculation software MatCalc. To validate the simulation results hot rolling experiments were performed by means of a laboratory mill. The grain structure evolution was analysed by electron backscatter diffraction (EBSD).

Sign in / Sign up

Export Citation Format

Share Document