The influence of stresses on martensitic transformation in Ni_(50)Mn_(19)Fe_6Ga_(25) melt-spun ribbons was studied. X-ray diffraction examination shows that the ribbon has a pure cubic L2_1 phase at room temperature and that the ribbon surface exhibits 100 preferentially oriented texture, while the 110 axis is about 45 deg tilted from the normal of the ribbon. By calculating the d spacing at different angles with the length direction of the ribbon, the tension was observed. It was found that the direction of the stress was along 010 direction of the oriented textured grains. During cooling, there is no obvious structural transition observed in as-spun ribbons. However, when the ribbons were annealed at 900 K for 24 h, the tension along 010 direction disappeared and the structural transition from cubic to tetragonal occurred obviously during cooling. It indicates that it is the tension along 010 direction to suppress the martensitic transformation in the as-spun ribbons.
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