TY - GEN
T1 - Mechanical response of isotropic graphite due to oxidation induced degradation
AU - Varona, Henry X.
AU - Faibussowitsch, Jacob
AU - Stephani, Kelly A.
AU - Johnson, Harley T.
AU - Elliott, Gregory S.
AU - Freund, Jonathan B.
AU - Panerai, Francesco
N1 - Funding Information:
This material is based in part upon work supported by the Department of Energy, National Nuclear Security Administration, under Award Number DE-NA0003963. This work was supported in part by the Department of Education through the Graduate Assistance in Areas of National Need Fellowship Program award P200A180050-19 at the University of Illinois Urbana-Champaign Department of Aerospace Engineering. The experiments were carried out in part in the Materials Research Laboratory Central Research Facilities and in part in the Advanced Materials Testing and Evaluation Laboratory, University of Illinois. We would like to thank Professor K. Matlack and Changgong Kim for their help with the ultrasonic evaluation and for allowing us to access their equipment. We would like to thank Professor Peter Kurath and Dr. David Ehrhardt for their help with mechanical loading experiments. H. X. Varona would like to thank Dr. Chris Byrne for his fruitful insights and suggestions on material characterization methods. The construction of the Flow Tube Reactor Furnace is partially supported by NASA Grant 80NSSC19M0164.
Publisher Copyright:
© 2022, American Institute of Aeronautics and Astronautics Inc. All rights reserved.
PY - 2022
Y1 - 2022
N2 - Durable thermal protection materials for hypersonic environments remain an important research path for atmospheric propulsion systems such as scramjets. Carbon materials are promising candidates; however, these materials have degradative interactions in oxidizing environments. This work investigates the relationship between oxidation and the material properties as exposure times are varied in a reactive environment to inform predictive models. Graphite specimens were prepared in a flow tube furnace to measure mass loss due to oxidation, change in material strength in tension and three-point bending configurations, and measurements of elastic constants using ultrasonic evaluation. Significant reductions in strength, Young’s modulus, and shear modulus occurred due to oxidation, with an increase in Poisson’s ratio being found. Numerical experiments using a cohesive zone model informed by the physical results are also explored for potential use in scramjet combustion simulations.
AB - Durable thermal protection materials for hypersonic environments remain an important research path for atmospheric propulsion systems such as scramjets. Carbon materials are promising candidates; however, these materials have degradative interactions in oxidizing environments. This work investigates the relationship between oxidation and the material properties as exposure times are varied in a reactive environment to inform predictive models. Graphite specimens were prepared in a flow tube furnace to measure mass loss due to oxidation, change in material strength in tension and three-point bending configurations, and measurements of elastic constants using ultrasonic evaluation. Significant reductions in strength, Young’s modulus, and shear modulus occurred due to oxidation, with an increase in Poisson’s ratio being found. Numerical experiments using a cohesive zone model informed by the physical results are also explored for potential use in scramjet combustion simulations.
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U2 - 10.2514/6.2022-1643
DO - 10.2514/6.2022-1643
M3 - Conference contribution
AN - SCOPUS:85123570875
SN - 9781624106316
T3 - AIAA Science and Technology Forum and Exposition, AIAA SciTech Forum 2022
BT - AIAA SciTech Forum 2022
PB - American Institute of Aeronautics and Astronautics Inc, AIAA
T2 - AIAA Science and Technology Forum and Exposition, AIAA SciTech Forum 2022
Y2 - 3 January 2022 through 7 January 2022
ER -