Fe-Ni-Mn maraging alloys show discontinuous coarsening of f.c.t. θ-NiMn precipitates along prior austenite grain boundaries (PAGBs) during isothermal aging. Heavy cold rolling of a solution annealed Fe-10Ni-7Mn (wt. %) maraging alloy and subsequent aging treatment at 773 K were found to result in the formation of a nanostructured material. Hardness measurement and transmission electron microscopy were used to study the aging behavior and microstructural evolution of the nanostructured alloy. At early stages of aging, an ultrafine grained structure was observed showing fine matrix precipitates. However, at later stages of aging, severe coarsening of precipitates was found. Consequently, a lamellar duplex microstructure composed of conventional precipitation hardened laths and ultrafine grained ferrite was identified in an intermediate aging time. Coarse f.c.t. θ-NiMn precipitates were identified among ultrafine grained ferrite. At longer stages of aging, evolution of the coarsening reaction were found to result in the development of the ultrafine grained ferrite regions.

Keywords: Nanostructure: Cold Rolling: Maraging: Precipitation: Coarsening

• Legal notice:
  

  Copyright (c) Pielaszek Research, all rights reserved.
  The above materials, including auxiliary resources, are subject to Publisher's copyright and the Author(s) intellectual rights. Without limiting Author(s) rights under respective Copyright Transfer Agreement, no part of the above documents may be reproduced without the express written permission of Pielaszek Research, the Publisher. Express permission from the Author(s) is required to use the above materials for academic purposes, such as lectures or scientific presentations.
  In every case, proper references including Author(s) name(s) and URL of this webpage: https://science24.com/paper/3873 must be provided.

1. Statistics of misorientation across grain boundaries in nanostructured Fe-Ni-Mn steel prepared by cold rolling and annealing of lath martensite
2. Determination of dislocation density and crystallite size distribution in deformed lath martensite by X-ray peak profile analysis
3. High resolution transmission electron microscopy study on the nano-scale twining of θ-NiMn precipitates in Fe-Ni-Mn maraging alloy