Masters Theses

Abstract

"The microstructure and mineralogical composition of direct bonded, 50 wt.% magnesia - 50 wt.% chrome ore refractory compositions containing controlled additions of silica were correlated with their compressive creep behavior in the temperature range 1450⁰ to 1550⁰C under stresses of 100 to 175 psi. Steady state creep rates were determined from the linear regression of the steady state regions of deformation on time. Apparent activation energies and deformation flow characteristics were determined from the temperature and stress dependence of the steady state creep rates. Silica contents up to 3.5 wt.% increased the amount of direct intergranular bonding which decreased the steady state creep rate. Apparent activation energies in the range 60.6 ł 17.0 to 75.2 ł 23.3 kcal/mole, i.e., not significantly different, indicated an overall rate-controlling creep process which was independent of silica content and appeared to be a function of the amount of direct intergranular bonding. The stress dependence of the steady state creep rates indicated a viscous creep process which was probably grain boundary sliding or deformation"--Abstract, page ii.

Advisor(s)

Day, D. E.

Committee Member(s)

Illegible signature
Moore, Robert E., 1930-2003

Department(s)

Materials Science and Engineering

Degree Name

M.S. in Ceramic Engineering

Sponsor(s)

Edward Orton Jr. Ceramic Foundation

Publisher

University of Missouri at Rolla

Publication Date

1968

Pagination

viii, 54 pages

Note about bibliography

Includes bibliographical references (pages 131-135).

Rights

© 1968 Maurice E. Green, Jr., All rights reserved.

Document Type

Thesis - Open Access

File Type

text

Language

English

Subject Headings

Materials -- Compression testingMaterials -- CreepRefractory materials

Thesis Number

T 2089

Print OCLC #

5995218

Electronic OCLC #

803605621

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