[1] [1] L Pawlowski. The Science and Engineering of Thermal Spray Coatings [M]. France: John Wiley & Sons, 2008: 301-325.

[2] [2] Y Gao, D Yang, J Gao. Characteristics of a plasma torch designed for very low pressure plasma spraying [J]. Journal of Thermal Spray Technology, 2012, 21(3-4): 740-744.

[3] [3] D Yang, B Tian, Y Gao. The lamellar- equiaxed microstructural transition of 316L coatings by low pressure plasma spraying [J]. Surface & Coatings Technology, 2013, 228: S72-S76.

[4] [4] Chen Xi. Heat Transfer and Flow in Thermal Plasma [M]. Beijing: Science Press, 2009: 34-43.

[5] [5] M Gindrat. Characterization of Supersonic Low Pressure Plasma Jets [D]. Lausanne: Swiss Federal Institute of Technology, 2004: 97-128.

[6] [6] Li Yonghui, Dong Lifang. Spatial distribution of atmospheric plasma jet temperature [J]. Acta Optica Sinica, 2013, 33(4): 0430003.

[7] [7] M Rajabian, D V Gravelle, S Vacquie. Measurements of temperatures and electron number density in an argon-nitrogen plasma jet generated by a dc torch- operation close to supersonic threshold [J]. Plasma Chemistry and Plasma Processing, 2004, 24(2): 261-284.

[8] [8] N Zhang, F Sun, L Zhu, et al.. Electron temperature and density of the plasma measured by optical emission spectroscopy in VLPPS conditions [J]. Journal of Thermal Spray Technology, 2011, 20(6): 1321-1327.

[9] [9] Li Xiafen, Zhou Weidong, Qian Huiguo, et al.. Electron temperature and density of soil plasma generated by laser ablation fast pulse discharge spectroscopy [J]. Acta Optica Sinica, 2011, 31(11): 1130001.

[10] [10] X Zhou, Y Li, J Wang, et al.. The temperature measurement of the electrothermal-chemical launcher plasma by atomic emission spectroscopy [J]. Plasma Science, 2001, 29(2): 360-364.

[11] [11] Dong Lifang, Tong Guoliang, Zhang Yu, et al.. Study on plasma temperature of a large area surface discharge by optical emission spectrum [J]. Spectroscopy and Spectral Analysis, 2014, 34(4): 919-921.

[12] [12] S Semenov, B Cetegen. Spectroscopic temperature measurements in direct current arc plasma jets used in thermal spray processing of materials [J]. Journal of Thermal Spray Technology, 2001, 10(2): 326-336.

[13] [13] Xu Wei, Wan Baonian. Spectroscopic method for measurement of plasma ion temperature and rotation velocity [J]. Acta Optica Sinica, 2003, 23(9): 1115-1118.

[14] [14] Li Tingjun. Emission Spectroscopy Analysis [M]. Beijing: Atomic Energy Press, 1983: 21-45.

[15] [15] S Yugeswaran, V Selvarajan. Electron number density measurement on a DC argon plasma jet by stark broadening of Ar I spectral line [J]. Vacuum, 2006, 81(3): 347-352.

[16] [16] N K Joshi, S N Sahasrabudhe, K P Sreekumar, et al.. Axial variation of electron number density in thermal plasma spray jets [J]. European Physical Journal D, 2003, 26: 215-219.