Orientation-dependent plastic deformation mechanisms and competition with stress-induced phase transformation in microscale NiTi

Ab initio prediction of temperature-dependent stability of heterogeneous B19′ phase in TiNi alloy using atomistically informed Eshelby’s ellipsoidal inclusion

“…Thus, to reveal the origin of the shape memory effect of this alloy, the mechanism of the phase transformation from B2 to B19' must be clarified. Many theoretical studies on this mechanism, especially using atomistic simulations, have been performed [7][8][9][10][11][12][13][14][15][16][17][18]. Although few molecular dynamics (MD) studies using empirical interatomic potential investigated the dynamics of phase transformation [12,16,18], majority of the studies based on density functional theory (DFT) calculations discuss the stability of the B19' structure by comparing its free energy or potential energy with that of B2 and other metastable atomic structures [7, 9-11, 13-15, 17].…”

“…Many theoretical studies on this mechanism, especially using atomistic simulations, have been performed [7][8][9][10][11][12][13][14][15][16][17][18]. Although few molecular dynamics (MD) studies using empirical interatomic potential investigated the dynamics of phase transformation [12,16,18], majority of the studies based on density functional theory (DFT) calculations discuss the stability of the B19' structure by comparing its free energy or potential energy with that of B2 and other metastable atomic structures [7, 9-11, 13-15, 17]. Despite these efforts, the stability of the B19' phase with respect to temperature remains unclear because of the discrepancy between theoretical and experimental observations.…”

Atomistic simulations of the deformation behavior of an Nb nanowire embedded in a NiTi shape memory alloy

“…MD simulations are very versatile and can provide a detailed understanding of the underlying mechanisms at the microscopic scale, if a reliable interatomic potential is available. For example, the martensitic transformation of NiTi SMAs has been successfully analyzed by performing MD simulations [29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44] using a reliable interatomic potential for the binary Ni-Ti system [45]. However, since no interatomic potential for the Nb-Ni-Ti ternary system is available yet, we have developed a new potential based on the second nearest-neighbor modified embedded-atom method (2NN MEAM) [46][47][48].…”

Molecular Dynamics Simulations of PtTi High-Temperature Shape Memory Alloys Based on a Modified Embedded-Atom Method Interatomic Potential

“…In such scenarios, atomistic simulation techniques, such as density functional theory (DFT) calculations and molecular dynamics (MD), could well support the experimental observations and even discover new attributes and their origins. For instance, numerous investigations employing large-scale MD simulations have effectively revealed origins to several phenomena [ 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 ]. For an MD simulation, an interatomic potential for the system of interest is essential, but the performance of the potential is another crucial aspect that is dependent on the model it is based on and the parameter fitting.…”