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Title: Observation of thermally etched grain boundaries with the FIB/TEM technique

Thermal etching is a method which is able to reveal and characterize grain boundaries, twins or dislocation structures and determine parameters such as grain boundary energies, surface diffusivities or study phase transformations in steels, intermetallics or ceramic materials. This method relies on the preferential transfer of matter away from grain boundaries on a polished sample during heating at high temperatures in an inert/vacuum atmosphere. The evaporation/diffusion of atoms at high temperatures results in the formation of grooves at the intersections of the planes of grain/twin boundaries with the polished surface. This work describes how the combined use of Focussed Ion Beam and Transmission Electron Microscopy can be used to characterize not only the grooves and their profile with the surface, but also the grain boundary line below the groove, this method being complementary to the commonly used scanning probe techniques. - Highlights: • Thermally etched low-carbon steel samples have been characterized by FIB/TEM • Grain boundary (GB) lines below the groove have been characterized in this way • Absence of ghost traces and large θ angle suggests that GB are not stationary but mobile • Observations correlate well with previous works and Mullins' investigations [22].
Authors:
 [1] ;  [2] ; ; ; ;  [3]
  1. Nanotechnology and advanced materials department, Materials and energy research centre (MERC), Karaj (Iran, Islamic Republic of)
  2. MATERALIA group, Department of Physical Metallurgy, (CENIM-CSIC), Centro Nacional de Investigaciones Metalúrgicas Av. Gregorio del Amo 8, 28040 Madrid (Spain)
  3. Institute for Materials Research, SPEME, University of Leeds, Leeds LS2 9JT (United Kingdom)
Publication Date:
OSTI Identifier:
22288663
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Characterization; Journal Volume: 84; Other Information: Copyright (c) 2013 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CARBON STEELS; CERAMICS; DISLOCATIONS; ETCHING; EVAPORATION; GRAIN BOUNDARIES; INTERMETALLIC COMPOUNDS; ION BEAMS; SURFACES; TRANSMISSION ELECTRON MICROSCOPY