Controlling the thermal expansion anisotropy of Mo5Si 3 and Ti5Si3 silicides

J. H. Schneibel; C. J. Rawn; E. A. Payzant; C. L. Fu

doi:10.1016/j.intermet.2004.02.035

Controlling the thermal expansion anisotropy of Mo₅Si ₃ and Ti₅Si₃ silicides

J. H. Schneibel, C. J. Rawn, E. A. Payzant, C. L. Fu

Materials Engineering

Research output: Contribution to journal › Article › peer-review

40 Scopus citations

Abstract

The coefficients of thermal expansion (CTE) of the tetragonal silicides Mo₅Si₃ and Ti₅Si₃ are highly anisotropic. The CTE anisotropy values, defined as the ratio of the CTEs in the c and a directions, CTE(c)/CTE(a), are 2.0 and 2.7 for Mo₅Si ₃ and Ti₅Si₃, respectively. Guided by first-principles calculations by Fu et al. (Acta Mater 51 (2003) 5033), ternary and quaternary alloying additions for reducing the anisotropy were selected. The smallest anisotropy, namely, 1.16, was found for a Mo-25Nb-12.5V-37.5Si (at.%) alloy. The experimentally determined reductions in CTE(c)/CTE(a) were not always as large as predicted because the measured site occupations of the ternary alloying elements were not as ideal as those calculated by Fu et al. Suitable alloying also reduces the CTE anisotropy of Ti₅Si ₃, but the reduction is not nearly as large as that claimed in previous publications.

Original language	English
Pages (from-to)	845-850
Number of pages	6
Journal	Intermetallics
Volume	12
Issue number	7-9 SPEC. ISS.
DOIs	https://doi.org/10.1016/j.intermet.2004.02.035
State	Published - Jul 2004

Funding

This research was sponsored by the Division of Materials Sciences and Engineering, Office of Basic Energy Sciences, and the Assistant Secretary for Energy Efficiency and Renewable Energy, Office of FreedomCAR and Vehicle Technologies, as part of the High Temperature Materials Laboratory User Program, Oak Ridge National Laboratory, managed by UT-Battelle, LLC, for the US Department of Energy under contract number DE-AC05-00OR22725.

Keywords

A. Silicides, various
B. Crystallography
B. Thermal properties
F. Diffraction

Access to Document

10.1016/j.intermet.2004.02.035

Cite this

@article{a14a841c870b48ae883760ed398dbc5c,

title = "Controlling the thermal expansion anisotropy of Mo5Si 3 and Ti5Si3 silicides",

abstract = "The coefficients of thermal expansion (CTE) of the tetragonal silicides Mo5Si3 and Ti5Si3 are highly anisotropic. The CTE anisotropy values, defined as the ratio of the CTEs in the c and a directions, CTE(c)/CTE(a), are 2.0 and 2.7 for Mo5Si 3 and Ti5Si3, respectively. Guided by first-principles calculations by Fu et al. (Acta Mater 51 (2003) 5033), ternary and quaternary alloying additions for reducing the anisotropy were selected. The smallest anisotropy, namely, 1.16, was found for a Mo-25Nb-12.5V-37.5Si (at.%) alloy. The experimentally determined reductions in CTE(c)/CTE(a) were not always as large as predicted because the measured site occupations of the ternary alloying elements were not as ideal as those calculated by Fu et al. Suitable alloying also reduces the CTE anisotropy of Ti5Si 3, but the reduction is not nearly as large as that claimed in previous publications.",

keywords = "A. Silicides, various, B. Crystallography, B. Thermal properties, F. Diffraction",

author = "Schneibel, {J. H.} and Rawn, {C. J.} and Payzant, {E. A.} and Fu, {C. L.}",

year = "2004",

month = jul,

doi = "10.1016/j.intermet.2004.02.035",

language = "English",

volume = "12",

pages = "845--850",

journal = "Intermetallics",

issn = "0966-9795",

publisher = "Elsevier",

number = "7-9 SPEC. ISS.",

}

TY - JOUR

T1 - Controlling the thermal expansion anisotropy of Mo5Si 3 and Ti5Si3 silicides

AU - Schneibel, J. H.

AU - Rawn, C. J.

AU - Payzant, E. A.

AU - Fu, C. L.

PY - 2004/7

Y1 - 2004/7

N2 - The coefficients of thermal expansion (CTE) of the tetragonal silicides Mo5Si3 and Ti5Si3 are highly anisotropic. The CTE anisotropy values, defined as the ratio of the CTEs in the c and a directions, CTE(c)/CTE(a), are 2.0 and 2.7 for Mo5Si 3 and Ti5Si3, respectively. Guided by first-principles calculations by Fu et al. (Acta Mater 51 (2003) 5033), ternary and quaternary alloying additions for reducing the anisotropy were selected. The smallest anisotropy, namely, 1.16, was found for a Mo-25Nb-12.5V-37.5Si (at.%) alloy. The experimentally determined reductions in CTE(c)/CTE(a) were not always as large as predicted because the measured site occupations of the ternary alloying elements were not as ideal as those calculated by Fu et al. Suitable alloying also reduces the CTE anisotropy of Ti5Si 3, but the reduction is not nearly as large as that claimed in previous publications.

AB - The coefficients of thermal expansion (CTE) of the tetragonal silicides Mo5Si3 and Ti5Si3 are highly anisotropic. The CTE anisotropy values, defined as the ratio of the CTEs in the c and a directions, CTE(c)/CTE(a), are 2.0 and 2.7 for Mo5Si 3 and Ti5Si3, respectively. Guided by first-principles calculations by Fu et al. (Acta Mater 51 (2003) 5033), ternary and quaternary alloying additions for reducing the anisotropy were selected. The smallest anisotropy, namely, 1.16, was found for a Mo-25Nb-12.5V-37.5Si (at.%) alloy. The experimentally determined reductions in CTE(c)/CTE(a) were not always as large as predicted because the measured site occupations of the ternary alloying elements were not as ideal as those calculated by Fu et al. Suitable alloying also reduces the CTE anisotropy of Ti5Si 3, but the reduction is not nearly as large as that claimed in previous publications.

KW - A. Silicides, various

KW - B. Crystallography

KW - B. Thermal properties

KW - F. Diffraction

UR - http://www.scopus.com/inward/record.url?scp=3142710933&partnerID=8YFLogxK

U2 - 10.1016/j.intermet.2004.02.035

DO - 10.1016/j.intermet.2004.02.035

M3 - Article

AN - SCOPUS:3142710933

SN - 0966-9795

VL - 12

SP - 845

EP - 850

JO - Intermetallics

JF - Intermetallics

IS - 7-9 SPEC. ISS.

ER -