Martensitic reorientation and shape-memory effect in initially textured polycrystalline Ti–Ni sheet

Effect of martensite reorientation and reorientation-induced plasticity on multiaxial transformation ratchetting of super-elastic NiTi shape memory alloy: New consideration in constitutive model

“…The details for the m a and n a are listed in Table 1. Martensite reorientation is caused by the movement of the interfaces between every two martensite variants (Liu et al, 1998;Xie et al, 1997;Thamburaja, 2005;Thamburaja et al, 2005). At the temperature lower than the martensite finish temperature M f , martensite reorientation occurs when applied stress reaches a critical value (under the uniaxial or multiaxial loading conditions); while, at the temperature higher than A f , this inelastic mechanism only occurs under the nonproportional loading condition.…”

“…S ij is the orientation tensor. The relation between the volume fraction of a-th martensite variant caused by the reorientation n a reo and the amount of deformation k ij can be constructed by the interaction matrix k aij (Thamburaja, 2005;Thamburaja et al, 2005), i.e., n a reo ¼ X 24 j>i X 23 i¼1 k aij k ij a ¼ 1; 2; . .…”

“…Also, the martensite reorientation mechanism is adopted by Yu et al (2014) to describe the thermo-mechanical deformation of super-elastic NiTi SMA under the non-proportional multiaxial loading condition. However, the crystal plasticity based constitutive models (Huang and Brinson, 1998;Gao et al, 2000;Huang et al, 2000;Anand and Gurtin, 2003;Thamburaja, 2005;Thamburaja et al, 2005;Patoor et al, 2006;Wang et al, 2008;Manchiraju and Anderson, 2010;Yu et al, 2014) only focus on the thermo-mechanical behavior of NiTi SMA within one loading-unloading cycle, and then the transformation ratchetting of super-elastic NiTi SMA and its evolution during the cyclic loading cannot been reasonably predicted by them. More recently, Yu et al (2013) constructed a cyclic crystal plasticity based model to describe the transformation ratchetting of super-elastic NiTi SMA.…”

“…However, only a martensite transformation mechanism is considered in the crystal plasticity based models mentioned above. Recently, Thamburaja (2005) and Thamburaja et al (2005) proposed a new crystal plasticity model to describe the shape memory effect of NiTi SMA by considering the martensite reorientation and detwinning. Also, the martensite reorientation mechanism is adopted by Yu et al (2014) to describe the thermo-mechanical deformation of super-elastic NiTi SMA under the non-proportional multiaxial loading condition.…”

Martensitic stabilization and defects induced by deformation in TiNi shape memory alloys

“…The shape memory effect arises from martensitic transformation and reorientation. So far, twinning [1][2][3][4] and martensitic transformation and reorientation [5][6] have already been systematically studied. However, there are few investigations on dislocation slip and defects introduced by deformation.…”