Improvement of shape memory effect in an Fe–Mn–Si–Cr–Ni–Nb–C alloy by NbC precipitated through ageing after pre-deformation

Further improvement of shape memory effect in a pre-deformed Fe–Mn–Si–Cr–Ni–Nb–C alloy by smaller NbC precipitated through electropulsing treatment

“…One was subjected to electropulsing treatment for different parameters. The other was subjected to ageing at 1073 K for different time which is the optimal ageing temperature reported by Wen and co-workers [11] (served as comparison). The electropulsing procedure was performed under ambient conditions, by capacitor discharge (5000 s, 300/200 V) with automatic triggering.…”

“…strain is afforded by stress-induced martensite transformation, not by plastic slip. More recent work by Kajiwara and co-workers [10] and Wen et al [11][12][13][14] showed that the shape recovery ratio can be further improved by aged after pre-deformation at room temperature. According to the Orowan theory, for a certain volume fraction, the smaller the size of the precipitates is, the greater the strengthening effect is [15].…”

Thermodynamic modeling and computational predictions of NbC precipitation in Fe–Mn–Si-based shape memory alloys by the classical nucleation and growth theories

“…However, the shape recovery rate of the solutionized alloys was only about 50%. Other research works also showed that NbC precipitates could improve the shape memory effect of Fe-Mn-Si-based alloys [22,23]. The improvement of shape memory effect by NbC precipitation can be ascribed to several factors [17,[23][24][25].…”

Shape memory in ferrous alloys

“…4.7 for a particle-free FeMnSiCrni alloy has been used in Fig. 4.8 as a benchmark to examine other work on alloys that contain precipitates (Baruj et al, 2002(Baruj et al, , 2004Dong et al, 2005;Wang et al, 2007). It can be seen from Fig.…”