In-flight temperature and velocity of powder particles of plasma-sprayed TiO2
Khor, Khiam Aik
Date of Issue2013
School of Mechanical and Aerospace Engineering
This paper relates to the in-flight temperature and velocity of TiO2 particles, an integral part of the systematic research on atmospheric plasma spraying of the material. Initial powder feedstock (32-45 μm, 100% rutile phase) was introduced into the plasma jet. Six parameters were selected to represent the versatility of the plasma system and their respective influences were determined according to basic one-at-a-time and advanced Taguchi design of experiments combined with the analysis of variance analytical tool. It was found that the measured temperatures varied from 2121 to 2830 K (33% variation), while the velocities of the particles were altered from 127 to 243 m/s (91% variation). Gun net power was detected as the most influential factor with respect to the velocity of the TiO2 particles (an increase of 8.4 m/s per 1-kW increase in net power). Spray distance was determined to have a major impact on the in-flight temperature (a decrease of 10 mm in spray distance corresponds to a drop of 36 K). A significant decrease in both characteristics was detected for an increasing amount of powder entering the plasma jet: A drop of 7.1 K and 1.4 m/s was recorded per every +1 g/min of TiO2 powder.
Journal of thermal spray technology
© 2013 ASM International. This paper was published in Journal of Thermal Spray Technology and is made available as an electronic reprint (preprint) with permission of ASM International. The paper can be found at the following official DOI: [http://dx.doi.org/10.1007/s11666-013-9993-9]. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper is prohibited and is subject to penalties under law.