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Title: Deformation behavior and joining of a MgF{sub 2} optical ceramic.

Abstract

Compressive deformation behavior of a polycrystalline magnesium fluoride (MgF{sub 2}) ceramic was investigated at temperatures ranging from 760 to 830 C in an argon atmosphere at strain rates between 2 x 10{sup -6} and 4 x 10{sup -5} s{sup -1}. Steady-state flow stresses increased with increasing strain rates and ranged between 2 and 38 MPa. Stress exponents of {approx}1.4 {+-} 0.2 were determined at temperatures >760 C, indicative of a viscous diffusion-controlled deformation mechanism. Activation energy, determined from flow stress as a function of temperature, at a constant strain rate, was {approx}476 {+-} 60 kJ/mol. Self-joining by plastic deformation of MgF{sub 2} was demonstrated at 830 C at a strain rate of 5 x 10{sup -6} s{sup -1}. The joined samples were characterized by optical transmission measurements and their transmittivity was {approx}80% of the unjoined sample in the 2.5--8 {micro}m wavelength range.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
EE
OSTI Identifier:
914935
Report Number(s):
ANL/ES/JA-58459
TRN: US200817%%20
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: J. Eur. Ceram. Soc.; Journal Volume: 27; Journal Issue: 11 ; 2007; Conference: Mechanical properties in advanced materials: recent insights; 6/7/06 - 6/11/06; Fuenteheridos, Spain
Country of Publication:
United States
Language:
ENGLISH
Subject:
36 MATERIALS SCIENCE; MAGNESIUM FLUORIDES; ACTIVATION ENERGY; CERAMICS; DEFORMATION; FLOW STRESS; JOINING

Citation Formats

Lorenso-Martin, C., Singh, D., Johnson, J., Routbort, J. L., and Nuclear Engineering Division. Deformation behavior and joining of a MgF{sub 2} optical ceramic.. United States: N. p., 2007. Web. doi:10.1016/j.jeurceramsoc.2007.02.187.
Lorenso-Martin, C., Singh, D., Johnson, J., Routbort, J. L., & Nuclear Engineering Division. Deformation behavior and joining of a MgF{sub 2} optical ceramic.. United States. doi:10.1016/j.jeurceramsoc.2007.02.187.
Lorenso-Martin, C., Singh, D., Johnson, J., Routbort, J. L., and Nuclear Engineering Division. Mon . "Deformation behavior and joining of a MgF{sub 2} optical ceramic.". United States. doi:10.1016/j.jeurceramsoc.2007.02.187.
@article{osti_914935,
title = {Deformation behavior and joining of a MgF{sub 2} optical ceramic.},
author = {Lorenso-Martin, C. and Singh, D. and Johnson, J. and Routbort, J. L. and Nuclear Engineering Division},
abstractNote = {Compressive deformation behavior of a polycrystalline magnesium fluoride (MgF{sub 2}) ceramic was investigated at temperatures ranging from 760 to 830 C in an argon atmosphere at strain rates between 2 x 10{sup -6} and 4 x 10{sup -5} s{sup -1}. Steady-state flow stresses increased with increasing strain rates and ranged between 2 and 38 MPa. Stress exponents of {approx}1.4 {+-} 0.2 were determined at temperatures >760 C, indicative of a viscous diffusion-controlled deformation mechanism. Activation energy, determined from flow stress as a function of temperature, at a constant strain rate, was {approx}476 {+-} 60 kJ/mol. Self-joining by plastic deformation of MgF{sub 2} was demonstrated at 830 C at a strain rate of 5 x 10{sup -6} s{sup -1}. The joined samples were characterized by optical transmission measurements and their transmittivity was {approx}80% of the unjoined sample in the 2.5--8 {micro}m wavelength range.},
doi = {10.1016/j.jeurceramsoc.2007.02.187},
journal = {J. Eur. Ceram. Soc.},
number = 11 ; 2007,
volume = 27,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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