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Title: Automation of a McBain-Bakr-type thermogravimetric analyzer using a digital image correlation technique

Abstract

Thermogravimetric analysis was used to obtain corrosion kinetics data for several materials in high-temperature environments. A thermogravimetric analyzer has been developed that uses a McBain-Bakr quartz spring balance in conjunction with a digital image acquisition and analysis package to accurately characterize materials through image correlation. This provides a new method for automatically measuring mass changes continuously with a variable resolution depending on the spring component. The decomposition of calcium oxalate was used to verify the validity of the technique. The results show two reactions, whose reaction temperatures were determined by the intercept method, upon heating to 650 deg. C. The mass loss at the first reaction temperature, 200 deg. C, was 20% and a 30% loss was observed at 500 deg. C. Comparison of the experimentally obtained results with those of other researchers who used commercial instruments suggests that the method of using digital image analysis in conjunction with a spring to monitor mass change is a viable and accurate replacement for automatic electrobalances and cathetometers for thermal analysis of materials. Additional comparison between corrosion tests performed on SA210 steel in H{sub 2}S using both a commercial thermobalance and the developed technique confirmed that high-temperature corrosion can be monitored accuratelymore » with the proposed method.« less

Authors:
; ;  [1]
  1. School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)
Publication Date:
OSTI Identifier:
20778744
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 77; Journal Issue: 2; Other Information: DOI: 10.1063/1.2169394; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; BALANCES; COMPARATIVE EVALUATIONS; CORROSION; IMAGES; MASS; QUARTZ; SPRINGS; STEELS; TEMPERATURE RANGE 0400-1000 K; THERMAL GRAVIMETRIC ANALYSIS

Citation Formats

Trexler, M.D., Sanders, T.H. Jr., and Singh, P.M. Automation of a McBain-Bakr-type thermogravimetric analyzer using a digital image correlation technique. United States: N. p., 2006. Web. doi:10.1063/1.2169394.
Trexler, M.D., Sanders, T.H. Jr., & Singh, P.M. Automation of a McBain-Bakr-type thermogravimetric analyzer using a digital image correlation technique. United States. doi:10.1063/1.2169394.
Trexler, M.D., Sanders, T.H. Jr., and Singh, P.M. Wed . "Automation of a McBain-Bakr-type thermogravimetric analyzer using a digital image correlation technique". United States. doi:10.1063/1.2169394.
@article{osti_20778744,
title = {Automation of a McBain-Bakr-type thermogravimetric analyzer using a digital image correlation technique},
author = {Trexler, M.D. and Sanders, T.H. Jr. and Singh, P.M.},
abstractNote = {Thermogravimetric analysis was used to obtain corrosion kinetics data for several materials in high-temperature environments. A thermogravimetric analyzer has been developed that uses a McBain-Bakr quartz spring balance in conjunction with a digital image acquisition and analysis package to accurately characterize materials through image correlation. This provides a new method for automatically measuring mass changes continuously with a variable resolution depending on the spring component. The decomposition of calcium oxalate was used to verify the validity of the technique. The results show two reactions, whose reaction temperatures were determined by the intercept method, upon heating to 650 deg. C. The mass loss at the first reaction temperature, 200 deg. C, was 20% and a 30% loss was observed at 500 deg. C. Comparison of the experimentally obtained results with those of other researchers who used commercial instruments suggests that the method of using digital image analysis in conjunction with a spring to monitor mass change is a viable and accurate replacement for automatic electrobalances and cathetometers for thermal analysis of materials. Additional comparison between corrosion tests performed on SA210 steel in H{sub 2}S using both a commercial thermobalance and the developed technique confirmed that high-temperature corrosion can be monitored accurately with the proposed method.},
doi = {10.1063/1.2169394},
journal = {Review of Scientific Instruments},
number = 2,
volume = 77,
place = {United States},
year = {Wed Feb 15 00:00:00 EST 2006},
month = {Wed Feb 15 00:00:00 EST 2006}
}
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