Influence of heat treatment on interface of Cu/Al bimetal composite fabricated by cold rolling

A copper/aluminum/copper sandwich clad sheet was fabricated by means of cold rolling process and heat treated with different temperature and time. The Al/Cu interface and its bond strength were investigated by SEM. TEM and peeling test. The results reveal that low temperature heat treatment can improve the morphology of Al/Cu interface and increase its bond strength. However high temperature and long time result in the formation of Al(2)Cu intermetallic compound layer, which is detrimental to the bond strength, and moreover, small Al(2)O(3) particles precipitate along the Al(2)Cu and Al interface. When the interlayer along Al/Cu interface grows to a certain thickness, the effect of heat treatment temperature and time become weak. For the present study, the reasonable heat treatment may be 423 K and 20 h. (C) 2011 Elsevier Ltd. All rights reserved.