Effect of Microstructure on Roll-Ability and Shape Memory Effect in Cu-Based Shape Memory Alloys

Abstract

Ternary Cu-12Al-4Mn and Cu-12Al-4Ni have been chosen for the present study and different alloying elements have been added in an attempt to further improve upon the shape memory properties in terms of the desired microstructure in the quenched condition. It has been observed that all compositions do not exhibit the martensitic structure on quenching and different types of martensitic phases are exhibited depending on the alloying constituents. Attempts have been made to roll the samples into thin sheets through multiple passes. It has been found that although the ternary base alloys can easily be rolled the quaternary alloys with both Mn and Ni make the sample brittle rendering it unsuitable for rolling. Also adding of Zn and Mg has not exhibited the desired microstructure for exhibiting the shape memory properties and also could not be rolled though these samples were not brittle. The ease of roll-ability has been compared between the alloys and correlated with the microstructure which helps in understanding which type of martensitic phase is useful in rolling the samples.