Masters Theses

Abstract

"An investigation of structure insensitive properties (lattice parameters, thermal expansion coefficients, densities, and imperfection) of gold and the alpha-phase of the gold-indium system was made. The gold-indium alloys were prepared from high purity (99.999%) gold and indium by melting both metals inside sealed quartz glass tubes which were first evacuated and then filled with helium gas. The solidified alloys were annealed and then examined by x-ray for homogeneity. The lattice constant of 99.999% pure gold at 25⁰C was found to be 4.07894 ł 0.00005 (corrected for refraction) Å. The coefficient of thermal expansion was 13.4 x 10⁻⁶⁰C⁻¹ between 15 and 65⁰C. Indium was found to expand the lattice of gold up to 12.57 atomic percent of indium, which marks the solid solubility limit of the alpha-phase of the Au-In system at 690⁰C. The agreement with previous determinations is good. The lattice constant of gold increased at a rate of approximately 0.0030 Å per atomic per cent of indium. The coefficient of thermal expansion of pure gold increased from 13.4 x 10⁻⁶⁰C⁻¹ to about 17.2 x 10⁻⁶⁰C⁻¹ with indium content up to about 7,5 atomic per cent indium and then remained approximately constant. A single crystal of 99.999% pure gold was found to have the density of 19.275 ł 0.0017 gm cm⁻³. the densities of Au-In alloys have been reported and were found to be lower than that of pure gold. vacancies were always present in the alpha-phase of the Au-In system. The number of vacant sites increased from 1.88 x 10²⁰ to 2.84 x 10 ²⁰ per cm³ as the indium concentration increased from 2 at.% to 6.55 at.% and then decreased to 1.55 x 10²⁰ per cm³ up to the solubility limit. The number of vacancies decreased approaching a limit of 0.0174 vacancies per indium atom at the solid solubility boundary"--Abstract, page 1-2.

Advisor(s)

Straumanis, Martin E., 1898-1973

Committee Member(s)

Leighly, Hollis P., 1923-2004
Findley, Marshall E., 1927-
Day, D. E.

Department(s)

Materials Science and Engineering

Degree Name

M.S. in Metallurgical Engineering

Sponsor(s)

Corrosion Research Council

Publisher

University of Missouri at Rolla

Publication Date

1967

Pagination

vi, 109 pages

Note about bibliography

Includes bibliographical references (leaves 53-61).

Rights

© 1967 Vinayak Keshavlal Patel, All rights reserved.

Document Type

Thesis - Open Access

File Type

text

Language

English

Library of Congress Subject Headings

Crystal lattices
Expansion (Heat) -- Measurement
Gold alloys
Indium

Thesis Number

T 2022

Print OCLC #

5987818

Electronic OCLC #

794226736

Included in

Metallurgy Commons

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