Microstructure of Chemical Vapor Transport Deposition Single Crystal Tungsten Coating Working at 1600°C

Abstract:

Thermionic energy conversion is a process by which thermal energy is transformed into electrical energy directly without the intermediate steps. Microstructure of Chemical Vapor Transport Deposited (CVTD) single crystal tungsten coating working at 1600°C for 1000 h was investigated using optical microscopy and electron backscatter diffraction (EBSD) technique. The experimental results showed that the etching morphology of single crystal tungsten coating was not clear compared to the etching morphology before working. The electro-etched surface of single crystal tungsten coating mainly consist of {110} crystal planes and {112} crystal planes before working at 1600°C. The surface of the single crystal tungsten coating mainly consists of near {110} crystal planes and near {112} crystal planes instead after working at 1600°C.

• Periodical: Materials Science Forum (Volume 849)
• Pages: 597-602
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.849.597
• Online since: March 2016
• Authors: Hong Tao Huang*, Yong Feng Wei, Jian Ping Zheng, Cheng Wen Tan
• Keywords: CVTD, Etching Morphology, Single Crystal Tungsten Coating, Thermionic Energy Converter

References

[1] S. Koff. Theoretical basis of thermionic energy conversion [M], Beijing: China Institute of Atomic Energy, (1999).

[2] Y.W. Lv. Study of tungsten monocrystal layers with a preferred crystallographic orientation obtained by Chemical vapor transportation deposition[D]. Beijing: Material Science School of Beijing Institute of Technology, (2012).

[3] Y.W. Lv, X.D. Yu. Deposition temperature effects on tungsten single-crystal layer by chemical vapor transport [J]. Journal of crystal growth, 329(2011)62-66.

DOI: 10.1016/j.jcrysgro.2011.06.040

[4] D. X Huang. Study on temperature field and volt-ampere characteristics calculation program for single-cell thermionic energy converter [D]. Beijing: China Institute of Atomic Energy, (1998).

[5] M S El-Genk, H.M. Xue. Two dimensional steady-state and transient analyses of single-cell thermionic fuel elements[J]. Nuclear technology, 108(1994)112-125.

DOI: 10.13182/nt94-a35047

[6] H.T. Huang, J.P. Zheng, Y.F. Wei. Microstructure Evolution of Single Crystal Tungsten Serving Under High Temperature for Long Time. Atomic Energy Science and Technology, 48(2014)528-534.

[7] K. Skotnicová , V.M. Kirillova , J. Drápala , G.S. Burchanov. Structural changes of single crystals of low-alloyed tungsten alloys at thermal cycling. Int. Journal of Refractory Metals and Hard Materials, 32(2012)61-65.

DOI: 10.1016/j.ijrmhm.2012.02.001