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Title: Investigation of carbon segregation during low temperature tempering in a medium carbon steel

Abstract

Low temperature tempering is important in improving the mechanical properties of steels. In this study, the thermoelectric power method was employed to investigate carbon segregation during low temperature tempering ranging from 110 °C to 170 °C of a medium carbon alloyed steel, combined with micro-hardness, transmission electron microscopy and atom probe tomography. Evolution of carbon dissolution from martensite and segregation to grain boundaries/interfaces and dislocations were investigated for different tempering conditions. Carbon concentration variation was quantified from 0.33 wt.% in quenching sample to 0.15 wt.% after long time tempering. The kinetic of carbon diffusion during tempering process was discussed through Johnson-Mehl-Avrami equation. - Highlights: • The thermoelectric power (TEP) was employed to investigate the low temperature tempering of a medium carbon alloyed steel. • Evolution of carbon dissolution was investigated for different tempering conditions. • Carbon concentration variation was quantified from 0.33 wt.% in quenching sample to 0.15 wt.% after long time tempering.

Authors:
 [1];  [2];  [3]; ;  [1];  [1];  [2]
  1. State Key Lab of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China)
  2. (China)
  3. Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration, Shanghai 200240 (China)
Publication Date:
OSTI Identifier:
22587167
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Characterization; Journal Volume: 117; Other Information: Copyright (c) 2016 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; 77 NANOSCIENCE AND NANOTECHNOLOGY; CARBON; CARBON STEELS; DISLOCATIONS; GRAIN BOUNDARIES; HARDNESS; MARTENSITE; QUENCHING; SEGREGATION; TEMPERATURE RANGE 0273-0400 K; TEMPERATURE RANGE 0400-1000 K; TEMPERING; TOMOGRAPHY; TRANSMISSION ELECTRON MICROSCOPY

Citation Formats

Xiao, Y., Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration, Shanghai 200240, Li, W., E-mail: weilee@sjtu.edu.cn, Zhao, H.S., Lu, X.W., Jin, X.J., E-mail: jin@sjtu.edu.cn, and Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration, Shanghai 200240. Investigation of carbon segregation during low temperature tempering in a medium carbon steel. United States: N. p., 2016. Web. doi:10.1016/J.MATCHAR.2016.04.021.
Xiao, Y., Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration, Shanghai 200240, Li, W., E-mail: weilee@sjtu.edu.cn, Zhao, H.S., Lu, X.W., Jin, X.J., E-mail: jin@sjtu.edu.cn, & Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration, Shanghai 200240. Investigation of carbon segregation during low temperature tempering in a medium carbon steel. United States. doi:10.1016/J.MATCHAR.2016.04.021.
Xiao, Y., Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration, Shanghai 200240, Li, W., E-mail: weilee@sjtu.edu.cn, Zhao, H.S., Lu, X.W., Jin, X.J., E-mail: jin@sjtu.edu.cn, and Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration, Shanghai 200240. 2016. "Investigation of carbon segregation during low temperature tempering in a medium carbon steel". United States. doi:10.1016/J.MATCHAR.2016.04.021.
@article{osti_22587167,
title = {Investigation of carbon segregation during low temperature tempering in a medium carbon steel},
author = {Xiao, Y. and Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration, Shanghai 200240 and Li, W., E-mail: weilee@sjtu.edu.cn and Zhao, H.S. and Lu, X.W. and Jin, X.J., E-mail: jin@sjtu.edu.cn and Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration, Shanghai 200240},
abstractNote = {Low temperature tempering is important in improving the mechanical properties of steels. In this study, the thermoelectric power method was employed to investigate carbon segregation during low temperature tempering ranging from 110 °C to 170 °C of a medium carbon alloyed steel, combined with micro-hardness, transmission electron microscopy and atom probe tomography. Evolution of carbon dissolution from martensite and segregation to grain boundaries/interfaces and dislocations were investigated for different tempering conditions. Carbon concentration variation was quantified from 0.33 wt.% in quenching sample to 0.15 wt.% after long time tempering. The kinetic of carbon diffusion during tempering process was discussed through Johnson-Mehl-Avrami equation. - Highlights: • The thermoelectric power (TEP) was employed to investigate the low temperature tempering of a medium carbon alloyed steel. • Evolution of carbon dissolution was investigated for different tempering conditions. • Carbon concentration variation was quantified from 0.33 wt.% in quenching sample to 0.15 wt.% after long time tempering.},
doi = {10.1016/J.MATCHAR.2016.04.021},
journal = {Materials Characterization},
number = ,
volume = 117,
place = {United States},
year = 2016,
month = 7
}
  • A local electrode atom probe has been used to analyze the solute partitioning during bainite transformation in a novel, nanocrystalline bainitic steel. Atom probe results show the absence of any partitioning of substitutional elements between the phases involved. The results are fully consistent with the diffusionless transformation of austenite to bainite. However, substitutional elements are expected to redistribute approaching an equilibrium phase boundary as the mixture of bainitic ferrite and retained austenite is tempered. The compositional analysis of the austenite/ferrite interface by atom probe tomography indicates that retained austenite decomposes during tempering before equilibrium is reached at the interface.
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