The effect of strengthening of austentie matrix by solution hardening, asuforming and the so-called "training" treatment on the shape memory behavior in Fe-Mn-Si based alloys has been studied. The addition of C to Fe-Mn-Si alloys is very effective for the improvement of shape memory effect due to the solution hardening of austenite. Thermomechanical treatments such as ausforming (deformation of austenite at temeperatures above Md) and repeated cycling (training, the repetition of slight deforamtion at room temperature and annealing at temperatures above Af) also improve the shape memory effect through the increase in the yield stress of austentie against a silp and the decrease in the critical stress for the formation of stress-induced epsilon martensite. These results suggest that the strenglth of austenite matrix is very improtant factor controlling the shpae memory effect in Fe-high Mn based alloys which undergo gamma (fcc) to dpsilon (hcp) martensitic transformation.
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