| The variation of SME by the cyclic deformation process that, Fe-30Mn-5Si-1Co is annealed at 600℃ after 4.5% deformation has been studied. The cyclic deformation effect was investigated by measuring SME using the method of tensile cyclic deformation and bending cyclic deformation. In the result of measurement of SME by the tensile cyclic deformation, SME reached at constant value with small deviation after gradually increased until 7 cycle. And the bending cyclic deformation showed similar result. Investigation of the variation of the microstructure by cyclic deformation using X-ray and optical microscope showed that by the cyclic deformation the amount of ε martensite increased and the variants were gradually oriented. We could know that the increase of ε martensite and the re-orientation of the variants is concerned with the increase of SME. And after the saturation, the SME was no more increased. In the result of the measurement of Neel temperature, Neel temperature gradually increased and reached at constant value. This means that the gradual stabilization of matrix hinders the increase of ε martensite. A_s showed the same inclination, too. The addition of Co to improve the shape memory effect of FeMnSi alloys did not affect the enhancement of corrosion property nearly. |
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