elib
DLR-Header
DLR-Logo -> http://www.dlr.de
DLR Portal Home | Imprint | Contact | Deutsch
Fontsize: [-] Text [+]

Convective coarsening of secondary dendrite arms

Ratke, Lorenz and Steinbach, Sonja (2007) Convective coarsening of secondary dendrite arms. In: Solidification Processing, pp. 14-17. Department of Engineering Materials, University of Sheffield, Great Britain. 5th Decennial International Conference on Solidification Processing, 2007-07-23 - 2007-07-25, Sheffield, UK. ISBN 0-9522507-4-8.

Full text not available from this repository.

Abstract

Coarsening of secondary dendrite arms in binary and multi-component alloys has been investigated theoretically and experimentally since decades and it generally is accepted that the secondary arms coarsen as the cube root of solidification time. Recent experimental investigation with AlSi, AlSiMg and AlSiCu alloys using gentle magnetic stirring in directional solidification experiments show that the coarsening kinetics are changed. Instead of a cube root relation it is observed that the secondary arms coarsen as the square root of solidification time. This paper describes a theoretical model for the secondary arm spacing based on an Ostwald ripening model with convective mass transport. The model predicts a coarsening in accordance with the experiments and correctly predicts increasing stirring magnitude accelerates coarsening. It also makes predictions on the effect of the permeability of the mush on the coarsening rate factor.

Document Type:Conference or Workshop Item (Speech, Paper)
Title:Convective coarsening of secondary dendrite arms
Authors:
AuthorsInstitution or Email of Authors
Ratke, LorenzUNSPECIFIED
Steinbach, SonjaUNSPECIFIED
Date:July 2007
Journal or Publication Title:Solidification Processing
Refereed publication:Yes
In ISI Web of Science:No
Page Range:pp. 14-17
Editors:
EditorsEmail
Jones, HowardUNSPECIFIED
Publisher:Department of Engineering Materials, University of Sheffield, Great Britain
Series Name:Proceedings of the 5th Decennial International Conference on Solidification Processing
ISBN:0-9522507-4-8
Status:Published
Keywords:secondary dendrite arms, dendrite arm coarsening, convection effects
Event Title:5th Decennial International Conference on Solidification Processing
Event Location:Sheffield, UK
Event Type:international Conference
Event Dates:2007-07-23 - 2007-07-25
Organizer:Howard Jones
HGF - Research field:Aeronautics, Space and Transport (old)
HGF - Program:Space (old)
HGF - Program Themes:W FR - Forschung unter Weltraumbedingungen (old)
DLR - Research area:Space
DLR - Program:W FR - Forschung unter Weltraumbedingungen
DLR - Research theme (Project):W - Vorhaben Materialforschung unter Mikro-g (old)
Location: Köln-Porz
Institutes and Institutions:Institute of Materials Physics in Space > Institute of Space Simulation > Center for Solidification of Undercooled Melts (ZEUS)
Deposited By: Dr.rer.nat. Sonja Steinbach
Deposited On:31 Jul 2007
Last Modified:27 Apr 2009 14:09

Repository Staff Only: item control page

Browse
Search
Help & Contact
Informationen
electronic library is running on EPrints 3.3.12
Copyright © 2008-2012 German Aerospace Center (DLR). All rights reserved.