Effect of carbon addition on the single crystalline magnetostriction of Fe-X (X=Al and Ga) alloys

The effect of carbon addition on the magnetostriction of Fe-Ga and Fe-Al alloys was investigated and is summarized in this study. It was found that the addition of carbon generally increased the magnetostriction over binary alloys of Fe-Ga and Fe-Al systems. The formation of carbide in the Fe-Ga-C alloys with a composition near D0(3) phase region decreased the magnetostriction drastically. Fe-Al-C and Fe-Ga-C alloys responded differently to thermal treatments; the magnetostriction in the quenched Fe-Al-C alloys is equal to or slightly lower than that of the slow cooled as is observed in binary Fe-Al alloy; in contrast, the magnetostriction is generally higher in quenched Fe-Ga-C alloys than slow cooled condition, consistent with the behavior of binary alloys of Fe-Ga. A significant increase in magnetostriction between 25% and 165% depending on the phase region in Fe-Ga-C alloys by quenching was observed in the A2+D0(3) two-phase region and D0(3) single phase region. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3311884]