Magneto-Mechanics of Magnetic Shape-Memory Crystals with Micropeened Surfaces

Presenter/Author/Student Information

Zane Harbison, Columbia UniversityFollow
Gianella Condor, Boise State UniversityFollow
Ammon Butler, Boise State UniversityFollow
John Martin, Boise State UniversityFollow
Shane Palmer, Boise State UniversityFollow
Paul Lindquist, Boise State UniversityFollow
Peter Müllner (Mentor), Boise State UniversityFollow

Additional Funding Sources

We acknowledge financial support through the National Science Foundation project Grant No. NSF-DMR 1710640. The project described was also supported by the National Science Foundation via the Research Experience for Undergraduates Site: Materials for Society (Award No. 1950305) and by the Micron School of Materials Science & Engineering at Boise State University.

Abstract

Magnetic shape-memory (MSM) materials use magnetic energy to generate large deformation. Nickel-Manganese-Gallium is a prominent MSM crystal that can be strained to 6% of its length. The alloy degrades and breaks after repeated loading, a behavior called fatigue. Bombarding the surface of the material with minuscule glass beads (micropeening) increases the number of loading cycles thousandfold; however, this decreases the maximum strain. In this project, stress and strain were measured before and after micropeening at different pressures to identify a quantitative relationship between process parameters and the dynamic material properties. Preliminary results show that micropeening at 25 psi preserves a large part of the strain while micropeening at 30 psi suppresses most of the strain.