The alloy Fe3Pd (30 at% Pd) undergoes a reversible structural phase transformation between FCC and FCT crystal structures at approximately 20°C. The FCT structure has lattice parameters (a/a0, a/a0, c/a0) relative to the parent phase with lattice parameter a0, where a/a0 > 1 and c/a0 < 1. In addition the three martensite variants of the FCT structure are also ferromagnetic. Magnetic measurements have shown that the easy magnetic axes correspond to the FCT axes with the lattice parameter a. A new instrument called a Magneto-Mechanical Testing Machine (MMTM) is used to study the magneto-mechanical response of this alloy. This instrument allows a specimen to be loaded mechanically uniaxially, while the magnetic field can be rotated in a plane containing the loading axis. In addition, the temperature of the specimen can be controlled while the microstructure on its surface is observed using an optical microscope equipped to view surface tilt using differential interference contrast (DIC). The results of experiments that control the rearrangement of the martensite variants through applied compressive loading and magnetic field, will be discussed.
|Original language||English (US)|
|Number of pages||12|
|Journal||Proceedings of SPIE - The International Society for Optical Engineering|
|State||Published - Jan 1 2002|
|Event||Smart Structures and Materials: Active Materials: Behavior and Mechanics - San Diego, CA, United States|
Duration: Mar 18 2002 → Mar 21 2002