Paper Title:
Influence of Primary Austenite on the Nucleation of Eutectic Cells
  Abstract

The solidification of gray cast iron starts with the precipitation of primary austenite. This phase nucleates either as columnar or equiaxed dendrites depending on whether nucleation occurs on the mould wall or on particles and impurities in the melt. In this work, the nucleation of primary austenite and its influence on the eutectic solidification has been investigated using different amounts of iron powder as inoculants. Besides, the influence of different cooling rates was also examined. Within each austenite grain there is a microstructure, and this microstructure was investigated using a color etching technique to reveal the eutectic cells and the dendritic network. It is shown how the cooling rate affects the dendritic network and the secondary dendrite arm spacing, and how the microstructure can be related to the macrostructure through dendrite arm spacing. The secondary dendrite arm spacing is a quantification of the primary austenite belonging to the primary solidification, and it will be shown how the eutectic cell size is related to the secondary dendrite arm spacing. The total amount of oxygen influences the microstructural dimensions. This effect, on the other hand, is influenced by the cooling rate. The number of eutectic cells versus eutectic cell size show two distinct behaviors depending on whether being inoculated with iron powder or a mixture of iron powder and commercial inoculant. The addition of a commercial inoculant decreases eutectic cell size and increases the number of cells, while iron powder almost only changes cell size.

  Info
Periodical
Edited by
Adel Nofal and Mohamed Waly
Pages
61-66
DOI
10.4028/www.scientific.net/KEM.457.61
Citation
L. Elmquist, A. Diószegi, P. Svidró, "Influence of Primary Austenite on the Nucleation of Eutectic Cells", Key Engineering Materials, Vol. 457, pp. 61-66, 2011
Online since
December 2010
Export
Price
$32.00
Share

In order to see related information, you need to Login.

In order to see related information, you need to Login.

Authors: Karl Martin Pedersen, Niels Tiedje
Abstract:Hypereutectic ductile iron was cast in green sand moulds with four plates with thickness of 1.5, 2, 3 and 4 mm in each mould. Temperatures...
63
Authors: You Ping Ma, Xiu Lan Li, Lei Yang
Abstract:The effect of carbon content on primary austenite stability of high chromium white cast iron(15.0wt.%) was investigated by means of optical...
1684
Authors: Mohamed Ahmed Taha Hanafi, Nahed A. El Mahallawy, Ahmed M. El-Sabbagh, Talat El-Benawy, Hasan F. Hadla
Abstract:Phases’ evolution during the solidification of a hypoeutectic 3.92% C-equivalence cast iron was modelled by considering the cooling history...
293
Authors: Fu Min Chu, Xin Hui Zu, Zhong Kui Zhao, Xiao Yun Jiang
Chapter 1: Materials Properties
Abstract:Microstructure and properties of the high carbon equivalent gray cast iron modified by the rare earth metal are investigated by optical...
962
Authors: Di Chu, Xu Dong Yue, Shu Xu, Jin Liu
Chapter 1: Material Science and Technology
Abstract:The influence of Nickel and Chromium alloy element on the primary austenite dendrite in D-type graphite was studied in this paper. The...
168