CIP extruded aluminium-lithium alloy composite: interfacial compatibility and mechanical properties

A series of Al-Li alloy composites have been developed using a cold isostatic press compaction and subsequent hot extrusion technique. The paper investigates the effect of using different reinforcement systems on the final mechanical properties of the composite measured with a Dynamic Mechanical Analyzer. For this study, the reinforcements were varied in terms of chemical type, geometric size and weight percent of the matrix. Whilst Li depletion was found to be negligible, results show that for the reinforcement to achieve strength improvements for the composite, proper particle dispersion and good interface bonding is necessary. Otherwise, addition of reinforcement may actually lower the composite strength due to agglomeration in the case of smaller particles, and a lack of interface bonding.