Thermophysical Properties of Gd₂O₃ Doped SrHfO₃ Ceramic

Abstract:

Gd₂O₃ (10mol%) doped SrHfO₃ (Sr (Hf_0.9Gd_0.1)O_2.95) was synthesized by solid state reaction method. The phase stability of the synthesized Sr (Hf_0.9Gd_0.1)O_2.95 powder at high temperature of 1450 ^oC for a long period and in a temperature range of RT-1400 ^oC was characterized by XRD and DSC, respectively. The thermal expansion coefficients (TECs) of bulk Sr (Hf_0.9Gd_0.1)O_2.95 were recorded by a high-temperature dilatometer, indicating that the phase transitions of SrHfO₃ are suppressed remarkably by doping Gd₂O₃. The thermal conductivity of bulk Sr (Hf_0.9Gd_0.1)O_2.95 at 1000 ^oC is ~1.95 W/m·K, which is ~11% lower than that of bulk 8YSZ.

• Periodical: Materials Science Forum (Volume 816)
• Pages: 237-241
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.816.237
• Online since: April 2015
• Authors: Wen Ma, Yi Ren, Xi Long Jin, Ya Hong Liang, Bao Dong Chen, Hong Ying Dong
• Keywords: Perovskite, Rare Earth Oxides, Thermal Barrier Coatings, Thermophysical Properties

References

[1] R. Miller, Thermal barrier coatings for aircraft engines: history and directions, J. Therm. Spray Technol. 6(1997) 35-42.

DOI: 10.1007/bf02646310

[2] U. Schulz, C. Leyens, K. Fritscher, M. Peters, B. Saruhan-Brings, O. Lavigne, J. Dorvaux, M. Poulain, R. Mévrel, M. Caliez, Some recent trends in research and technology of advanced thermal barrier coatings, Aerospace Sci. Technol. 7(2003) 73-80.

DOI: 10.1016/s1270-9638(02)00003-2

[3] N. Padture, M. Gell, E. Jordan, Thermal barrier coatings for gas-turbine engine applications, Science 296(2002) 280-284.

DOI: 10.1126/science.1068609

[4] A. Rabiei, A. Evans, Failure mechanisms associated with the thermally grown oxide in plasma-sprayed thermal barrier coatings, Acta Mater. 48(2000) 3963-3976.

DOI: 10.1016/s1359-6454(00)00171-3

[5] J. Ilavsky, J. Stalick, Phase composition and its changes during annealing of plasma-sprayed YSZ, Surf. Coat. Technol. 127(2000) 120-129.

DOI: 10.1016/s0257-8972(00)00562-4

[6] R. Jones, D. Mess, Improved tetragonal phase stability at 1400oC with scandia, yttria-stabilized zirconia, Surf. Coat Technol. 86(1996) 94-101.

DOI: 10.1016/s0257-8972(96)03006-x

[7] C. Levi, Emerging materials and processes for thermal barrier systems, Curr. Opin. Solid State Mater Sci. 8(2004) 77-91.

[8] R. Gadow, M. Lischka, Lanthanum hexaaluminate - novel thermal barrier coatings for gas turbine applications - materials and process development, Surf. Coat. Technol. 151-152(2002) 392-399.

DOI: 10.1016/s0257-8972(01)01642-5

[9] S. Yamanaka, T. Maekawa, H. Muta, T. Matsuda, S. Kobayashi, K. Kurosaki, Thermal and mechanical properties of SrHfO3, J Alloy Compounds 381(2004) 295-300.

DOI: 10.1016/j.jallcom.2004.03.113

[10] B. Kennedy, C. Howard, High-temperature phase transitions in SrHfO3, Phys. Rev. B 60(1999) 2972-2975.

[11] R. Shannon, Revised effective ionic radii and systematic studies of interatomic distance in halides and chalcogenides, Acta Cryst. A32(1976) 751-767.

DOI: 10.1107/s0567739476001551

[12] W. Ma, D. Mack, R. Vassen, D. Stӧver, Perovskite-type strontium zirconate as a new material for thermal barrier coatings, J. Am. Ceram. Soc. 91(2008) 2630-2635.

DOI: 10.1111/j.1551-2916.2008.02472.x

[13] J. Leitner, P. Chuchvalec and D. Sedmidubský, A. Strejc, P. Abrman, Estimation of heat capacities of solid mixed oxides, Thermochim. Acta 395(2003) 27-46.

DOI: 10.1016/s0040-6031(02)00177-6

[14] K. Schlichting, N. Padture, P. Klemens, Thermal conductivity of dense and porous yttria-stabilized zirconia, J. Mater. Sci. 36(2011) 3003-3010.