Role of Si on the shape memory property of Fe-Mn-Si-C based alloys

Abstract

Abstract. Si content dependence of the shape memory effect (SME) associated with the -martensitic transformation has been investigated in Fe-17Mn-xSi-0.3C (x=0,2,4,6) alloys (mass%). By conducting tensile deformations and subsequent heating to above the A f , it has been found that reduction of mere 2% Si content from 6% to 4% obviously deteriorates the SME. The Neel and M s temperatures in both Fe-17Mn4%Si-0.3C and Fe-17Mn6%Si-0.3C alloys are content with the conditions concerning the good SME. By obtaining stress-strain curves at various temperatures, it has been found that the Fe17Mn-4Si-0.3C alloy has similar critical stresses for -martensitic transformation and slip deformation to the critical stresses in the Fe-17Mn-6Si-0.3C alloy. As a consequence, the SME in Fe-Mn-Si-C system sometimes does not appear, even ifmartensitic transformation preferentially occurs.