2011/09/30 by A. Banerjee, P. Chaddah, S. Dash +6 · 39 citations
Chemistry · Materials Science · Physics and Astronomy · #Alloy #Austenite #Chemistry #Condensed matter physics #Crystallography #Diffusionless transformation #Magnetic and transport properties of perovskites and related materials #Magnetic field #Magnetization #Martensite #Materials science #Metallurgy #Metastability #Microstructure #Nucleation #Phase (matter) #Physics #Quantum mechanics #Relaxation (psychology) #Shape Memory Alloy Transformations #Supercooling #Thermodynamics #cond-mat.mtrl-sci #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.84.214420
published in Physical Review B 84(21) (American Physical Society) · Title, abstract, introduction, conclusions are modified
openalex publication_date 2011/12/12 · arxiv created 2011/12/14 · arxiv updated 2015/05/29 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We study through the time evolution of magnetization the low-temperature (T) dynamics of the metastable coexisting phases created by traversing different paths in magnetic field H and T space in a shape memory alloy system, Ni45Co5Mn38Sn12. It is shown that these coexisting phases consisting of a fraction of kinetically arrested austenite phase and a remaining fraction of low-T equilibrium martensitic phase undergo a slow relaxation to low magnetization (martensitic) state but with very different thermomagnetic history-dependent rates at the same T and H. We discovered that, when the nucleation of the martensitic phase is initiated at much lower T through the de-arrest of the glasslike arrested state contrasted with the respective first-order transformation (through supercooling at much higher T), the long-time relaxation rate scales with the nonequilibrium phase fraction but has a very weak dependence on T. This is explained on the basis of the H-T path dependent size of the critical radii of the nuclei and the subsequent growth of the equilibrium phase through the motion of the interface.