skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: An Atomistic Modeling Study of Alloying Element Impurity Element, and Transmutation Products on the cohesion of A Nickel E5 {l_brace}001{r_brace} Twist Grain Boundary

Abstract

Atomistic modeling methods were employed to investigate the effects of impurity elements on the metallurgy, irradiation embrittlement, and environmentally assisted cracking of nickel-base alloys exposed to nuclear environments. Calculations were performed via ab initio atomistic modeling methods to ensure the accuracy and reliability of the results. A Griffith-type fracture criterion was used to quantitatively assess the effect of elements or element pairs on the grain boundary cohesive strength. In order of most embrittling to most strengthening, the elements are ranked as: He, Li, S, H, C, Zr, P, Fe, Mn, Nb, Cr, and B. Helium is strongly embrittling (-2.04 eV/atom lowering of the Griffith energy), phosphorus has little effect on the grain boundary (0.1 eV/atom), and boron offers appreciable strengthening (1.03 eV/atom increase in the Griffith energy). Calculations for pairs of elements (H-Li, H-B, H-C, H-P, and H-S) show little interaction on the grain boundary cohesive energy, so that for the conditions studied, linear superposition of elemental effects is a good approximation. These calculations help explain metallurgical effects (e.g. why boron can strengthen grain boundaries), irradiation embrittlement (e.g. how boron transmutation results in grain boundary embrittlement), as well as how grain boundary impurity elements can affect environmentally assisted cracking (i.e.more » low temperature crack propagation and stress corrosion cracking) of nickel-base alloys.« less

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
Lockheed Martin Corporation, Schenectady, NY 12301 (US)
Sponsoring Org.:
US Department of Energy (US)
OSTI Identifier:
821509
Report Number(s):
LM-03K047
TRN: US0400810
DOE Contract Number:  
AC12-00SN39357
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: 16 Jun 2003
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; 74 ATOMIC AND MOLECULAR PHYSICS; ALLOYS; BORON; CRACK PROPAGATION; EMBRITTLEMENT; FRACTURES; HELIUM I; IRRADIATION; METALLURGICAL EFFECTS; METALLURGY; NICKEL; PHOSPHORUS; SIMULATION; STRESS CORROSION; TRANSMUTATION

Citation Formats

G.A. Young Jr., R. Najafabadi, W. Strohmayer, D.G. Baldrey, B. Hamm, J. Harris, J. Sticht, and E. Wimmer. An Atomistic Modeling Study of Alloying Element Impurity Element, and Transmutation Products on the cohesion of A Nickel E5 {l_brace}001{r_brace} Twist Grain Boundary. United States: N. p., 2003. Web. doi:10.2172/821509.
G.A. Young Jr., R. Najafabadi, W. Strohmayer, D.G. Baldrey, B. Hamm, J. Harris, J. Sticht, & E. Wimmer. An Atomistic Modeling Study of Alloying Element Impurity Element, and Transmutation Products on the cohesion of A Nickel E5 {l_brace}001{r_brace} Twist Grain Boundary. United States. doi:10.2172/821509.
G.A. Young Jr., R. Najafabadi, W. Strohmayer, D.G. Baldrey, B. Hamm, J. Harris, J. Sticht, and E. Wimmer. Mon . "An Atomistic Modeling Study of Alloying Element Impurity Element, and Transmutation Products on the cohesion of A Nickel E5 {l_brace}001{r_brace} Twist Grain Boundary". United States. doi:10.2172/821509. https://www.osti.gov/servlets/purl/821509.
@article{osti_821509,
title = {An Atomistic Modeling Study of Alloying Element Impurity Element, and Transmutation Products on the cohesion of A Nickel E5 {l_brace}001{r_brace} Twist Grain Boundary},
author = {G.A. Young Jr. and R. Najafabadi and W. Strohmayer and D.G. Baldrey and B. Hamm and J. Harris and J. Sticht and E. Wimmer},
abstractNote = {Atomistic modeling methods were employed to investigate the effects of impurity elements on the metallurgy, irradiation embrittlement, and environmentally assisted cracking of nickel-base alloys exposed to nuclear environments. Calculations were performed via ab initio atomistic modeling methods to ensure the accuracy and reliability of the results. A Griffith-type fracture criterion was used to quantitatively assess the effect of elements or element pairs on the grain boundary cohesive strength. In order of most embrittling to most strengthening, the elements are ranked as: He, Li, S, H, C, Zr, P, Fe, Mn, Nb, Cr, and B. Helium is strongly embrittling (-2.04 eV/atom lowering of the Griffith energy), phosphorus has little effect on the grain boundary (0.1 eV/atom), and boron offers appreciable strengthening (1.03 eV/atom increase in the Griffith energy). Calculations for pairs of elements (H-Li, H-B, H-C, H-P, and H-S) show little interaction on the grain boundary cohesive energy, so that for the conditions studied, linear superposition of elemental effects is a good approximation. These calculations help explain metallurgical effects (e.g. why boron can strengthen grain boundaries), irradiation embrittlement (e.g. how boron transmutation results in grain boundary embrittlement), as well as how grain boundary impurity elements can affect environmentally assisted cracking (i.e. low temperature crack propagation and stress corrosion cracking) of nickel-base alloys.},
doi = {10.2172/821509},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jun 16 00:00:00 EDT 2003},
month = {Mon Jun 16 00:00:00 EDT 2003}
}

Technical Report:

Save / Share: