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Title: A physics-based crystallographic modeling framework for describing the thermal creep behavior of Fe-Cr alloys

Abstract

This Report addresses the Milestone M2MS-16LA0501032 of NEAMS Program (“Develop hardening model for FeCrAl cladding), with a deadline of 09/30/2016. Here we report a constitutive law for thermal creep of FeCrAl. This Report adds to and complements the one for Milestone M3MS-16LA0501034 (“Interface hardening models with MOOSE-BISON”), where we presented a hardening law for irradiated FeCrAl. The last component of our polycrystal-based constitutive behavior, namely, an irradiation creep model for FeCrAl, will be developed as part of the FY17 Milestones, and the three regimes will be coupled and interfaced with MOOSE-BISON.

Authors:
 [1];  [1];  [1];  [1]
+ Show Author Affiliations
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE Office of Nuclear Energy (NE)
OSTI Identifier:
1342837
Report Number(s):
LA-UR-16-27585
DOE Contract Number:
AC52-06NA25396
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Wen, Wei, Capolungo, Laurent, Patra, Anirban, and Tome, Carlos. A physics-based crystallographic modeling framework for describing the thermal creep behavior of Fe-Cr alloys. United States: N. p., 2017. Web. doi:10.2172/1342837.
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Wen, Wei, Capolungo, Laurent, Patra, Anirban, & Tome, Carlos. A physics-based crystallographic modeling framework for describing the thermal creep behavior of Fe-Cr alloys. United States. doi:10.2172/1342837.
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Wen, Wei, Capolungo, Laurent, Patra, Anirban, and Tome, Carlos. Thu . "A physics-based crystallographic modeling framework for describing the thermal creep behavior of Fe-Cr alloys". United States. doi:10.2172/1342837. https://www.osti.gov/servlets/purl/1342837.
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@article{osti_1342837,
title = {A physics-based crystallographic modeling framework for describing the thermal creep behavior of Fe-Cr alloys},
author = {Wen, Wei and Capolungo, Laurent and Patra, Anirban and Tome, Carlos},
abstractNote = {This Report addresses the Milestone M2MS-16LA0501032 of NEAMS Program (“Develop hardening model for FeCrAl cladding), with a deadline of 09/30/2016. Here we report a constitutive law for thermal creep of FeCrAl. This Report adds to and complements the one for Milestone M3MS-16LA0501034 (“Interface hardening models with MOOSE-BISON”), where we presented a hardening law for irradiated FeCrAl. The last component of our polycrystal-based constitutive behavior, namely, an irradiation creep model for FeCrAl, will be developed as part of the FY17 Milestones, and the three regimes will be coupled and interfaced with MOOSE-BISON.},
doi = {10.2172/1342837},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Feb 02 00:00:00 EST 2017},
month = {Thu Feb 02 00:00:00 EST 2017}
}
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Technical Report:
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DOI:  10.2172/1342837
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    In this work, a physics-based thermal creep model is developed based on the understanding of the microstructure in Fe-Cr alloys. This model is associated with a transition state theory based framework that considers the distribution of internal stresses at sub-material point level. The thermally activated dislocation glide and climb mechanisms are coupled in the obstacle-bypass processes for both dislocation and precipitate-type barriers. A kinetic law is proposed to track the dislocation densities evolution in the subgrain interior and in the cell wall. The predicted results show that this model, embedded in the visco-plastic self-consistent (VPSC) framework, captures well the creepmore » behaviors for primary and steady-state stages under various loading conditions. We also discuss the roles of the mechanisms involved.« less

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