Influence of annealing temperature on the shape memory effect of Fe–14Mn–5Si–9Cr–5Ni alloy after training treatment

Microstructural evaluation on shape recovery in stainless Fe-Mn-Si-Cr-Ni-Co SMA processed by wire drawing

“…These steels have the capacity to recover its original shape by the reverse transformation of stress induced ε martensite [1][2][3][4] . Some factors that influence in the capacity of shape memory recovery have been studied, such as the amount of pre-strain, thermomechanical training, alloying elements, deformation temperature and annealing temperature [5][6][7][8][9][10][11][12] . According to Akhondzadeh et al 5 , the annealing temperature is the more effective parameter to control the shape memory effect due to microstructural changes developed in the parent phase, influencing directly the reverse martensitic transformation.…”

“…Some factors that influence in the capacity of shape memory recovery have been studied, such as the amount of pre-strain, thermomechanical training, alloying elements, deformation temperature and annealing temperature [5][6][7][8][9][10][11][12] . According to Akhondzadeh et al 5 , the annealing temperature is the more effective parameter to control the shape memory effect due to microstructural changes developed in the parent phase, influencing directly the reverse martensitic transformation. Usually, for iron based shape memory alloy, the shape recovery (SR) presented in the literature is related to the total shape recovery (TSR) and no mention to the elastic shape recovery (ESR) or superelastic shape recovery (SESR) is done [5][6][7][8][9][10] .…”

“…According to Akhondzadeh et al 5 , the annealing temperature is the more effective parameter to control the shape memory effect due to microstructural changes developed in the parent phase, influencing directly the reverse martensitic transformation. Usually, for iron based shape memory alloy, the shape recovery (SR) presented in the literature is related to the total shape recovery (TSR) and no mention to the elastic shape recovery (ESR) or superelastic shape recovery (SESR) is done [5][6][7][8][9][10] . As shown by Otubo et al 11 , for a similar alloy with no cobalt addition, in a solution treated condition, the major contribution to TSR comes from shape recovery (SR) due to shape memory effect on heating.…”

Phase transformation during mechano-synthesis of nanocrystalline/amorphous Fe–32Mn–6Si alloys

“…This non-thermoelastic or semi-thermoelastic conversion occurred by the creation of stacking faults (SFs) due to the movement of the Shockley partial dislocations (a γ /6 <112>) in the parent phase. SFs are suitable sites for nucleation of the martensite phase; eventually, the ε-phase can be formed by their overlap [12,[17][18][19][20][21][22][23].…”

“…This non-thermoelastic or semi-thermoelastic conversion occurred by the creation of stacking faults (SFs) due to the movement of the Shockley partial dislocations (a γ /6 <112>) in the parent phase. SFs are suitable sites for nucleation of the martensite phase; eventually, the ε-phase can be formed by their overlap [12,[17][18][19][20][21][22][23].Although induction melting under an argon gas atmosphere is widely utilized to produce Fe-based SMAs, solid-state routes such as mechanical alloying (MA) can be used to produce the alloys in the powder form [24]. During MA, by applying the high energy collision between ball and particles and consequently the repeated cold welding and fracture of the powders, not only is the alloying process attained but also the synthesis of the non-equilibrium structures such as supersaturated solid solutions, nanocrystalline and amorphous structures, and intermetallic compounds is possible [24][25][26][27][28].…”