Phase Field Simulation of Ni4Ti3 Precipitation in Porous NiTi Shape Memory Alloys under Applied Stresses
This study presents the simulation of evolution of Ni4Ti3 variants during stress-assisted aging of NiTi alloys containing nano-scale pores with different sizes, by using phase field approach. The simulation shows that the higher level of applied stress can cause more Ni4Ti3 particles precipitated around pores than that of lower level stress, regardless of pore size; the large pores can “capture” more precipitates while less particles precipitated around the small pores. Moreover, the precipitation of Ni4Ti3 particles exhibits different regional preferences near pores, which means the unixial compressive stress can result in inhomogeneous Ni4Ti3 particle distribution.
Jian-Feng Nie and Allan Morton
C. B. Ke et al., "Phase Field Simulation of Ni4Ti3 Precipitation in Porous NiTi Shape Memory Alloys under Applied Stresses", Materials Science Forum, Vols. 654-656, pp. 1504-1507, 2010