For Libraries For Publication Open Access Downloads About Us Contact Us
Paper Titles
Principles of Microstructural Formation in Semi-Solid Metal Processing
p.1
Integrated Development of Controled Semi-Solid Casting Technology for Super-Cooled Ductile Iron
p.9
Experimental Determination of the Parameters for Modelling Semi-Solid Processing
p.16
Interaction of Key Variables During Rheocasting: Importance of Microstructure, Fraction Solid and Flow Velocity
p.24
Semi Solid Casting and Forging of Steel
p.34
Development of an Advanced Rheocasting Process and Its Applications
p.44
Determination of Solidification Parameters Used for the Prediction of the Thixoformability of Several Steel Alloys
p.54
Design and Production of New Aluminum Thixotropic Alloys for the Manufacture of Structural Components by Semisolid Die Casting
p.58
Application of the Continuous Rheoconversion Process (CRPTM) to Low Temperature HPDC-Part II: Alloy Development & Validation
p.64

Principles of Microstructural Formation in Semi-Solid Metal Processing

Article Preview

Abstract:

The essential first step in semi-solid forming is to obtain a high grain density during the initial stages of solidification of an alloy melt. This is usually done by a combination of cooling and convection. If the grain density is too low, the resulting structure is one of conventional coarse dendrites, unsuitable for semi-solid forming. At higher grain densities, fine dendrites grow that can be coarsened to a spheroidal structure in a short enough time to be of practical interest for semi-solid forming. If the initial grain density is still higher, the grains grow in a fully spheroidal manner. Thus there are two distinctly different paths to formation of the desired structure: 1) coarsening of fine dendrites, and 2) direct spheroidal growth. We are beginning to understand quantitatively the conditions necessary to form spheroids in these two different ways.

You might also be interested in these eBooks
Semi-Solid Processing of Alloys and Composites View Preview

Info:

Periodical:

Solid State Phenomena (Volumes 116-117)

Pages:

1-8

DOI:

https://doi.org/10.4028/www.scientific.net/SSP.116-117.1

Citation:

Cite this paper

Online since:

October 2006

Authors:

Merton C. Flemings, R. Andy Martinez

Keywords:

Coarsening, Semi-Solid Metal, Solidification, Spheroidal Microstructure

Export:

RIS, BibTeX

Price:

Permissions CCC:

Request Permissions

Permissions PLS:

Request Permissions

Сopyright:

© 2006 Trans Tech Publications Ltd. All Rights Reserved

Share:

Citation:

References

[1] R. A. Martinez and M. C. Flemings, Metall Trans, 36A (2005), 2205.

Google Scholar

[2] J.A. Yurko, M.C. Flemings, R.A. Martinez, Die Casting Engineer, 48 (2004), 5052.

Google Scholar

[3] T.F. Bower, H.D. Brody, M.C. Flemings, Metall Trans, 236 (1966), 624.

Google Scholar

[4] B.P. Bardes, M.C. Flemings, Trans AFS, 66 (1974), 406.

Google Scholar

[5] S. Annavarapu, and R.D. Doherty, Acta Metall Mater, 43 (1995), 3207.

Google Scholar

[6] R.E. Spear and G.R. Gardner, Trans AFS, 71 (1963), 209.

Google Scholar

[7] T.Z. Kattamis, J. C. Coughlin, M.C. Flemings, Metall Trans, 239 (1967) 1504.

Google Scholar

[8] D.R. Poirier, S. Ganesan, M. Andrews, P. Ocansey, Mat Sci and Eng A, 148 (1991), 289.

Google Scholar

[9] D.H. Kirkwood, Mat Sci and Eng, 65 (1984), 101.

Google Scholar

[10] M. Chen and T.Z. Kattamis, Mat Sci and Eng, A247 (1988), 239.

Google Scholar

[11] R. A. Martinez, PhD Thesis, Department of Materials Science and Engineering, MIT, (2004).

Google Scholar

[12] R.A. Martinez, A. Karma, M.C. Flemings, submitted to Metall Trans A, accepted Feb. (2006).

Google Scholar

© 2025 Trans Tech Publications Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies. For open access content, terms of the Creative Commons licensing CC-BY are applied.
Scientific.Net is a registered trademark of Trans Tech Publications Ltd.