TY - JOUR
T1 - Air plasma-material interactions at the oxidized surface of the PM1000 nickel-chromium superalloy
AU - Panerai, Francesco
AU - Marschall, Jochen
AU - Thömel, Jan
AU - Vandendael, Isabelle
AU - Hubin, Annick
AU - Chazot, Olivier
N1 - Funding Information:
The authors are thankful to the European Space Agency for the procurement of Plasmatron samples and for the support with the spectral reflectivity measurements. Jochen Marschall's contributions were supported by the Aerospace Materials for Extreme Environments Program of the Air Force Office of Scientific Research through contract FA9550-11-1-0201 . The U.S. Government is authorized to reproduce and distribute reprints for Governmental purposes notwithstanding any copyright notation thereon. The views and conclusions contained herein are those of the authors and should not be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of the Air Force Research Laboratory or the U.S. Government.
Publisher Copyright:
© 2014 Elsevier B.V. All rights reserved.
PY - 2014
Y1 - 2014
N2 - Nickel-based superalloys are promising options for the thermal protection systems of hypersonic reentry vehicles operating under moderate aerothermal heating conditions. We present an experimental study on the interactions between PM1000, an oxide dispersion strengthened nickel-chromium superalloy, and air plasma at surface temperatures between 1000 and 1600 K and pressures of 1500,7500 and 10,000 Pa. Pre-oxidized PM1000 specimens are tested in high-enthalpy reactive air plasma flows generated by the Plasmatron wind tunnel at the von Karman Institute for Fluid Dynamics. Microscopic analysis of plasma-exposed specimens shows enhanced damage to the chromia scale at the lowest plasma pressure. Elemental surface analysis reveals the loss of Cr and the enhancement of Ni at the scale surface. A thermodynamic analysis supports the accelerated volatilization of Cr 2 O 3 and the relative stability of NiO in the presence of atomic oxygen. Changes in the reflectance and emissivity of the oxidized surfaces due to plasma-exposure are presented. The catalytic efficiencies for dissociated air species recombination are determined as a function of surface temperature and pressure through a numerical rebuilding procedure and are compared with values presented in the literature for the same material.
AB - Nickel-based superalloys are promising options for the thermal protection systems of hypersonic reentry vehicles operating under moderate aerothermal heating conditions. We present an experimental study on the interactions between PM1000, an oxide dispersion strengthened nickel-chromium superalloy, and air plasma at surface temperatures between 1000 and 1600 K and pressures of 1500,7500 and 10,000 Pa. Pre-oxidized PM1000 specimens are tested in high-enthalpy reactive air plasma flows generated by the Plasmatron wind tunnel at the von Karman Institute for Fluid Dynamics. Microscopic analysis of plasma-exposed specimens shows enhanced damage to the chromia scale at the lowest plasma pressure. Elemental surface analysis reveals the loss of Cr and the enhancement of Ni at the scale surface. A thermodynamic analysis supports the accelerated volatilization of Cr 2 O 3 and the relative stability of NiO in the presence of atomic oxygen. Changes in the reflectance and emissivity of the oxidized surfaces due to plasma-exposure are presented. The catalytic efficiencies for dissociated air species recombination are determined as a function of surface temperature and pressure through a numerical rebuilding procedure and are compared with values presented in the literature for the same material.
KW - Nickel based superalloys thermal protection system
KW - Oxidation
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U2 - 10.1016/j.apsusc.2014.08.017
DO - 10.1016/j.apsusc.2014.08.017
M3 - Article
AN - SCOPUS:84922569943
SN - 0169-4332
VL - 316
SP - 385
EP - 397
JO - Applied Surface Science
JF - Applied Surface Science
IS - 1
ER -