TY - JOUR
T1 - Effects of Ir or Ta Alloying Addition on Interdiffusion of L12-Ni3Al
AU - Garimella, N.
AU - Ode, M.
AU - Ikeda, M.
AU - Murakami, H.
AU - Sohn, Y. H.
N1 - Funding Information:
Financial support from CAREER Award of National Science Foundation (DMR-0238356) is gratefully acknowledged. Any opinions, findings, and conclusions or recommendations expressed in this manuscript are those of the authors and do not necessarily reflect the view of the National Science Foundation.
PY - 2008/9
Y1 - 2008/9
N2 - Ternary interdiffusion in L12-Ni3Al with ternary alloying additions of Ir and Ta was investigated at 1473 K using solid-to-solid diffusion couples. Average ternary interdiffusion coefficients were determined from an integration of interdiffusion fluxes calculated directly from experimental concentration profiles. The magnitude of over(over(D, ̃), -)NiNi and over(over(D, ̃), -)AlAl coefficients was determined to be much larger than that of over(over(D, ̃), -)IrIr and over(over(D, ̃), -)TaTa coefficients. Ir substituting in Ni-site influenced the interdiffusion of Ni significantly, and over(over(D, ̃), -)NiIrAl coefficients were determined to be large and positive. On the other hand, Ta substituting for Al influenced the interdiffusion of Al significantly, and over(over(D, ̃), -)AlTaNi coefficients were determined to be large and positive. An excellent agreement was found with ternary interdiffusion coefficients determined by Boltzmann-Matano analysis. Profiles of concentrations and interdiffusion fluxes were also examined to estimate binary interdiffusion coefficients in Ni3Al, and tracer diffusion coefficients of Ir (14.7 × 10-16 ± 1.4 × 10-16 m2/s) and Ta (2.6 × 10-16 ± 2.4 × 10-16 m2/s) in Ni3Al.
AB - Ternary interdiffusion in L12-Ni3Al with ternary alloying additions of Ir and Ta was investigated at 1473 K using solid-to-solid diffusion couples. Average ternary interdiffusion coefficients were determined from an integration of interdiffusion fluxes calculated directly from experimental concentration profiles. The magnitude of over(over(D, ̃), -)NiNi and over(over(D, ̃), -)AlAl coefficients was determined to be much larger than that of over(over(D, ̃), -)IrIr and over(over(D, ̃), -)TaTa coefficients. Ir substituting in Ni-site influenced the interdiffusion of Ni significantly, and over(over(D, ̃), -)NiIrAl coefficients were determined to be large and positive. On the other hand, Ta substituting for Al influenced the interdiffusion of Al significantly, and over(over(D, ̃), -)AlTaNi coefficients were determined to be large and positive. An excellent agreement was found with ternary interdiffusion coefficients determined by Boltzmann-Matano analysis. Profiles of concentrations and interdiffusion fluxes were also examined to estimate binary interdiffusion coefficients in Ni3Al, and tracer diffusion coefficients of Ir (14.7 × 10-16 ± 1.4 × 10-16 m2/s) and Ta (2.6 × 10-16 ± 2.4 × 10-16 m2/s) in Ni3Al.
KW - A. Nickel aluminides, based on NiAl
KW - B. Diffusion
KW - D. Site occupancy
KW - F. Electron microprobe
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U2 - 10.1016/j.intermet.2008.06.011
DO - 10.1016/j.intermet.2008.06.011
M3 - Article
AN - SCOPUS:50249106913
VL - 16
SP - 1095
EP - 1103
JO - Intermetallics
JF - Intermetallics
SN - 0966-9795
IS - 9
ER -