1996/03/07 by Madan Rao, Rao, Madan, Surajit Sengupta +1
Earth and Planetary Sciences · Engineering · Materials Science · Physics and Astronomy · #Condensed Matter (cond-mat) #FOS: Physical sciences #Metallic Glasses and Amorphous Alloys #Solidification and crystal growth phenomena #cond-mat #nanoparticles nucleation surface interactions
paper · pdf · doi:10.48550/arxiv.cond-mat/9603049
5 pages, REVTEX, includes 2 .eps figures To appear in "Defects in Condensed Media", eds. K. Krishan, C. S. Sundar and V. Kumar (SciTech Publ. Ltd., Switzerland, 1996)
arxiv created 1996/03/07 · openalex publication_date 1996/03/07 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Martensites are metastable phases, possessing a characteristic morphology, usually formed during a fast quench accross a structural transition. We attempt to understand these morphological features using a coarsegrained free energy functional \cal F[ε; Φ] which contains, in addition to the usual strain fields εij (the `` order parameter'' for the transition), the ``vacancy'' field ϕ which arises due to the geometric mismatch at a parent-product interface. The relaxation of this mismatch is slow compared to typical front propagation times and hence ϕ is essentially frozen in the reference frame of the growing martensite front. Minimisation of \cal F then automatically yeilds typical martensite morphologies. We demonstrate this in two dimensions for the square to rhombus transformation and obtain internally twinned martensites, which grow as thin strips, for ``hard'' martensites (e.g., Fe-based alloys) or with a `single-interface', for ``soft'' martensites (e.g., In-Tl alloys).