Optimization of foaming heat treatment parameters in fabricating aluminum foams by accumulative roll-bonding

Aluminum foam sheets produced by accumulative roll-bonding process via decomposition of a blowing agent، have a great capability for fabricating sandwich structures including aluminum foam cores. A comprehensive design of these structures demands the optimization of foaming parameters، particularly foaming heat treatment. Using preheated furnaces as alternative to infrared image furnaces، which are commonly used for foaming heat treatment، could lead to easier and less expensive foam production. Optimizing the parameters for such heat treatment is the main subject of this study. In order to achieve a preform for foaming heat treatment tests، TiH2 powders were distributed in the aluminum matrix by 7 passes of repeated roll-bonding and cutting. The fabricated preforms were heat treated to convert to the foams in a preheated resistance furnace. Optimized heat treatment parameters for achieving the best combination of porosity and cell morphology were extracted. The best result was aluminum foam with 37. 2 % porosity.