Effect of Stretching on Extrusions for Residual Stress and Distortion
M. E. Karabin and R. W. Schultz, ALCOA Technical Center
Track: VALUE-ADDED PROCESSES - Extrusion
ABSTRACT --- Processing steps in the extrusion process can induce residual
stresses in the product. This is particularly true during rapid quenching.
Quenching induced stresses can be reduced by the stretching process. It is
shown that the level of stress in the product after stretching is related to the
strength gradient over the cross-section. This stress distribution can be
manifested in the form of a bow after the extrusion is released from the stretcher.
A prediction of bow is compared to measurements of bow in a long part. It is
shown that the bow, after stretching in a long part, is not only affected by the
strength gradient, but by its weight, cross-section geometry, and support
© Extrusion Technology for Aluminum Profiles Foundation (ET Foundation). All rights reserved. No part of The Proceedings may be reproduced in any form without the express written permission of the ET Foundation.