Please use this identifier to cite or link to this item:
Title: Viscosity–Shear Rate Relationship during the Thixoforming of HP9/4/30 Steel
Authors: Omar, M.Z.
Atkinson, Helen V.
Palmiere, E.J.
Howe, A.A.
Kapranos, Plato
First Published: Oct-2006
Publisher: Trans Tech Publications
Citation: Solid State Phenomena, 2006, 116-117, pp. 677-680
Abstract: Thixoforming involves shaping metal components in the semi-solid state. Work on the thixoforming of high temperature materials, such as steel, is still at its initial stage; this is mainly due to the high processing temperatures involved and the potential for oxidation. For thixoforming to be possible, it is preferable for an alloy to have an appreciable melting range and before forming the microstructure must ideally consist of solid metal spheroids in a liquid matrix. This paper discusses the thixoforming load versus displacement curves of HP9/4/30 steel semi-solid slugs under compression. The data from the corresponding load-displacement curves is converted into viscosity against shear rate adopting Stefan’s equation for flow between two parallel planes. The viscosity at processing conditions, i.e. at processing temperatures in the range of 1470 to 1480°C and zero to two minutes soak times, showed a rapid decrease initially, which corresponds to a rapid breakdown in the structure, followed by a steady decrease to a near constant value with increasing rate. The work shows pseudoplasticity (or shear-thinning) behaviour of the HP9/4/30 semi-solid slurries. This data would be required for modeling the die fill with these slurries.
ISSN: 1662-9779
Type: Conference paper
Description: Full text of this item is not currently available on the LRA. The final published version is available at, Doi: 10.4028/
Appears in Collections:Conference Papers & Presentations, Dept. of Engineering
Published Articles, Dept. of Engineering

Files in This Item:
There are no files associated with this item.

Items in LRA are protected by copyright, with all rights reserved, unless otherwise indicated.