Effect of substitutional solid solution on dislocation nucleation in Fe₃Al intermetallic alloys

Abstract

Dislocation nucleation in solid solutions of body-centered-cubic intermetallic Fe₃Al alloys was investigated by means of nanoindentation and measurement of the pop-in load of samples with different Cr content. It is clearly shown that the Cr solute element in the Fe₃Al intermetallic alloy increases the pop-in load, i.e. shear stress, required for dislocation nucleation in a previously dislocation-free region. Changes in pop-in load track closely with changes in elastic properties, which can be interpreted within the framework of the universal features of metallic bonding as a change in the interatomic potential, as proposed by Rose et al.

Keywords:

• nanoindentation
• dislocations
• mechanical properties
• Fe₃Al

Acknowledgments

The authors thank Dr. Martin Palm from MPIE Düsseldorf for providing the samples and many valuable discussions, and the Hysitron and Physical Electronics GmbH for giving us the chance to use the Performech™ controller.