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Title: Martensitic transformation of pure iron at a grain boundary: Atomistic evidence for a two-step Kurdjumov-Sachs–Pitsch pathway

Abstract

Using classical molecular dynamics simulations and the Meyer-Entel interaction potential, we study the martensitic transformation pathway in a pure iron bi-crystal containing a symmetric tilt grain boundary. Upon cooling the system from the austenitic phase, the transformation starts with the nucleation of the martensitic phase near the grain boundary in a plate-like arrangement. The Kurdjumov-Sachs orientation relations are fulfilled at the plates. During further cooling, the plates expand and merge. In contrast to the orientation relation in the plate structure, the complete transformation proceeds via the Pitsch pathway.

Authors:
;  [1]
  1. Physics Department and Research Center OPTIMAS, University Kaiserslautern, Erwin-Schrödinger-Straße, D-67663 Kaiserslautern (Germany)
Publication Date:
OSTI Identifier:
22611383
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Advances; Journal Volume: 6; Journal Issue: 8; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; AUSTENITIC STEELS; COOLING; CRYSTALS; GRAIN BOUNDARIES; INTERACTIONS; IRON; MARTENSITIC STEELS; MOLECULAR DYNAMICS METHOD; NUCLEATION; ORIENTATION; PHASE TRANSFORMATIONS; PLATES; SIMULATION; SYMMETRY; TRANSFORMATIONS

Citation Formats

Meiser, Jerome, and Urbassek, Herbert M., E-mail: urbassek@rhrk.uni-kl.de. Martensitic transformation of pure iron at a grain boundary: Atomistic evidence for a two-step Kurdjumov-Sachs–Pitsch pathway. United States: N. p., 2016. Web. doi:10.1063/1.4961739.
Meiser, Jerome, & Urbassek, Herbert M., E-mail: urbassek@rhrk.uni-kl.de. Martensitic transformation of pure iron at a grain boundary: Atomistic evidence for a two-step Kurdjumov-Sachs–Pitsch pathway. United States. doi:10.1063/1.4961739.
Meiser, Jerome, and Urbassek, Herbert M., E-mail: urbassek@rhrk.uni-kl.de. 2016. "Martensitic transformation of pure iron at a grain boundary: Atomistic evidence for a two-step Kurdjumov-Sachs–Pitsch pathway". United States. doi:10.1063/1.4961739.
@article{osti_22611383,
title = {Martensitic transformation of pure iron at a grain boundary: Atomistic evidence for a two-step Kurdjumov-Sachs–Pitsch pathway},
author = {Meiser, Jerome and Urbassek, Herbert M., E-mail: urbassek@rhrk.uni-kl.de},
abstractNote = {Using classical molecular dynamics simulations and the Meyer-Entel interaction potential, we study the martensitic transformation pathway in a pure iron bi-crystal containing a symmetric tilt grain boundary. Upon cooling the system from the austenitic phase, the transformation starts with the nucleation of the martensitic phase near the grain boundary in a plate-like arrangement. The Kurdjumov-Sachs orientation relations are fulfilled at the plates. During further cooling, the plates expand and merge. In contrast to the orientation relation in the plate structure, the complete transformation proceeds via the Pitsch pathway.},
doi = {10.1063/1.4961739},
journal = {AIP Advances},
number = 8,
volume = 6,
place = {United States},
year = 2016,
month = 8
}
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