Quantum parameters for guiding the design of Ti alloys with shape memory and/or low elastic modulus

Abstract

Electronic structure calculations based on density functional theory have been applied to clusters of titanium with different alloying elements in order to obtain quantum parameters that give some information on the interaction between the mother and alloying atoms. Average values of these parameters weighted with the molar fractions have been calculated for 146 titanium alloys that exhibit shape memory and/or low elastic modulus. These values have been mapped in order to identify zones that group the alloys with either property. This information was used as a guide for designing seven new alloys with desired properties. These have been microstructurally and mechanically characterized; the results confirm the usefulness of the method.

Keywords:

• titanium alloys
• shape memory alloys
• low elastic modulus
• density functional theory

Acknowledgements

The authors wish to thank the Spanish Ministry of Science and Technology for financial support through grants MAT2005-07244-C03-01, CTQ2005-08459-CO2-01 and BIO2004-05436. They also want to acknowledge the referees for useful comments.