Prediction of Nitrogen Diffusivity in ��-ferrite Based on Thermodynamics
Jae-gil JUNG1,Seok-jae LEE2
1. Light Metal Division,Korea Institute of Materials Science,Changwon 642-831,Korea 2. Division of Advanced Materials Engineering,Research Center for Advanced Materials Development,Chonbuk National University,Jeonju 561-756,Korea
Prediction of Nitrogen Diffusivity in ��-ferrite Based on Thermodynamics
Jae-gil JUNG1,Seok-jae LEE2
1. Light Metal Division,Korea Institute of Materials Science,Changwon 642-831,Korea 2. Division of Advanced Materials Engineering,Research Center for Advanced Materials Development,Chonbuk National University,Jeonju 561-756,Korea
ժҪ A thermodynamic based equation to predict the diffusivity of nitrogen in ��ferrite was investigated in consideration of the equilibrium nitrogen concentration. The temperature-dependent jump distance calculated from the lattice parameter of ferrite was used to derive the frequency factor as a function of temperature. The calculation accuracy for nitrogen diffusivity using the proposed thermodynamic based equation was improved by comparing the calculation results using previous empirical equations based on Arrhenius type relationship with measured diffusivity of nitrogen for ��ferrite at different temperatures.
Abstract��A thermodynamic based equation to predict the diffusivity of nitrogen in ��ferrite was investigated in consideration of the equilibrium nitrogen concentration. The temperature-dependent jump distance calculated from the lattice parameter of ferrite was used to derive the frequency factor as a function of temperature. The calculation accuracy for nitrogen diffusivity using the proposed thermodynamic based equation was improved by comparing the calculation results using previous empirical equations based on Arrhenius type relationship with measured diffusivity of nitrogen for ��ferrite at different temperatures.
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Seok-Jae Lee
E-mail: seokjaelee@jbnu.ac.kr
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Jae-gil JUNG,Seok-jae LEE. Prediction of Nitrogen Diffusivity in ��-ferrite Based on Thermodynamics[J]. �й������ڿ���, 2015, 22(8): 743-745.
Jae-gil JUNG,Seok-jae LEE. Prediction of Nitrogen Diffusivity in ��-ferrite Based on Thermodynamics. Chinese Journal of Iron and Steel, 2015, 22(8): 743-745.