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Title: Magnetism and Solid Solution Effects in NiAI (40% AI) Alloys

Abstract

The solid solution effects of ternary additions of transition elements in intermetallic Ni-40% Al were investigated by both experimental studies and theoretical calculations. Co solute atoms when sitting at Ni sublattice sites do not affect the lattice parameter and hardening behavior of Ni-40Al. On the other hand, Fe, Mn, and Cr solutes, which are mainly on Al sublattice sites, substantially expand the lattice parameter and produce an unusual solid solution softening effect. First-principles calculations predict that these solute atoms with large unfilled d-band electrons develop large magnetic moments and effectively expand the lattice parameter when occupying Al sublattice sites. The theoretical predictions were verified by both electron loss-energy spectroscopy (EELS) analyses and magnetic susceptibility measurements. The observed softening behavior can be explained quantitatively by the replacement of Ni anti-site defects (potent hardeners) by Fe, Mn, and Cr anti-site defects with smaller atom size mismatch between solute and Al atoms. This study has led to the identification of magnetic interaction as an important physical parameter affecting the solid solution hardening in intermetallic alloys containing transition elements.

Authors:
 [1];  [1];  [1];  [1];  [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
931242
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Progress in Materials Science; Journal Volume: 52
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; NICKEL BASE ALLOYS; ALUMINIUM ALLOYS; COBALT; IRON; MANGANESE; CHROMIUM; DEFECTS; HARDENING; LATTICE PARAMETERS; MAGNETIC MOMENTS; SOLID SOLUTIONS; SOLUTES; METALLURGICAL EFFECTS

Citation Formats

Liu, Chain T, Fu, Chong Long, Chisholm, Matthew F, Thompson, James R, Krcmar, Maja, and Wang, Xun-Li. Magnetism and Solid Solution Effects in NiAI (40% AI) Alloys. United States: N. p., 2007. Web. doi:10.1016/j.pmatsci.2006.10.014.
Liu, Chain T, Fu, Chong Long, Chisholm, Matthew F, Thompson, James R, Krcmar, Maja, & Wang, Xun-Li. Magnetism and Solid Solution Effects in NiAI (40% AI) Alloys. United States. doi:10.1016/j.pmatsci.2006.10.014.
Liu, Chain T, Fu, Chong Long, Chisholm, Matthew F, Thompson, James R, Krcmar, Maja, and Wang, Xun-Li. Mon . "Magnetism and Solid Solution Effects in NiAI (40% AI) Alloys". United States. doi:10.1016/j.pmatsci.2006.10.014.
@article{osti_931242,
title = {Magnetism and Solid Solution Effects in NiAI (40% AI) Alloys},
author = {Liu, Chain T and Fu, Chong Long and Chisholm, Matthew F and Thompson, James R and Krcmar, Maja and Wang, Xun-Li},
abstractNote = {The solid solution effects of ternary additions of transition elements in intermetallic Ni-40% Al were investigated by both experimental studies and theoretical calculations. Co solute atoms when sitting at Ni sublattice sites do not affect the lattice parameter and hardening behavior of Ni-40Al. On the other hand, Fe, Mn, and Cr solutes, which are mainly on Al sublattice sites, substantially expand the lattice parameter and produce an unusual solid solution softening effect. First-principles calculations predict that these solute atoms with large unfilled d-band electrons develop large magnetic moments and effectively expand the lattice parameter when occupying Al sublattice sites. The theoretical predictions were verified by both electron loss-energy spectroscopy (EELS) analyses and magnetic susceptibility measurements. The observed softening behavior can be explained quantitatively by the replacement of Ni anti-site defects (potent hardeners) by Fe, Mn, and Cr anti-site defects with smaller atom size mismatch between solute and Al atoms. This study has led to the identification of magnetic interaction as an important physical parameter affecting the solid solution hardening in intermetallic alloys containing transition elements.},
doi = {10.1016/j.pmatsci.2006.10.014},
journal = {Progress in Materials Science},
number = ,
volume = 52,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
  • No abstract prepared.
  • Tellurium in excess of the stoichiometric value is added to alloys based on Sb/sub 1.5/Be/sub 0.5/Te/sub 3/ solid solution to obtain the optimum carrier concentration, and part of this is segregated as a tellurium-rich eutectic at the grain boundaries. Annealing increases the thermo-emf ..cap alpha.. and resistivity rho, which is due to the tellurium in the second phase dissolving, and this acts as a donor and reduces the hole concentration. We have examined the properties of alloys made by zone melting after annealing in air at 390, 470, and 520 K.
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