Analysis of Metal Flow of Aluminum through Long Choked Die Channels
The mechanics of metal flow through long choked die channels have been investigated in unlubricated hot aluminum extrusion. Experiments were performed in a laboratory press at an earlier occasion by letting a grid pattern introduced into the billet flow down into the choked die channel to appear adjacent to the channel wall. The grid pattern was then revealed to characterize the metal flow in the channel. A 2D-model of the extrusion process was made. The model was applied to study the conditions in the extrusion experiments and in this model good similarity was obtained with the experiment. New knowledge regarding the metal flow through a choked die channel have been obtained this way, such as; contact conditions, presence of sticking and sliding zones, friction conditions in the sliding contact zone and the velocity profile over the cross-section of the channel.
A. Erman Tekkaya and Nooman Ben Khalifa
H. S. Valberg "Analysis of Metal Flow of Aluminum through Long Choked Die Channels", Key Engineering Materials, Vol. 424, pp. 145-152, 2010