Advantages of Cascade Plasma Generators for Thermal Spraying
Dr. Vladimir Belashchenko1, Prof. Oleg P. Solonenko2 and Andrey Smirnov2, 1TSD LLC, 9 Irving Drive, Concord, NH 03301, 2Plasmodynamic of dispersed systems, Institute of Theoretical and Applied Mechanics, SB RAS, Novosibirsk, Russia, 4/1 Institutskaya Av., Novosibirsk, 630090, Russia

The paper presents an analysis of potential advantages offered to thermal spraying by the implementation of cascade plasma generators (CPG) in APS, LPPS and several other areas. The paper provides evidence that the modular designed single cathode CPG helps eliminate the following major disadvantages of conventional plasma torches: plasma parameters drifting, 1-5 kHz pulsing of plasma parameters, as well as excessive erosion of electrodes. Stable plasma results in higher quality, homogeneity and reproducibility of plasma sprayed coatings. In addition, CPG offers an extremely wide operating window, which  allows better control of plasma parameters, particle dwell time and, consequently, particle temperature and velocity within a wide range by generating high enthalpy quasi-laminar plasmas, medium enthalpy transient plasmas, as well as relatively low enthalpy turbulent plasmas. As a result, the CPG-based plasma torch satisfies a variety of present and future technological requirements and also achieves practically all parameters of plasma jets generated by plasma torches presently used for thermal spraying. Stable operation, flexibility with plasma gases as well as wide operating window of CPG should help significantly improve the existing plasma spraying processes and coatings, and also help develop new advanced processes and coatings.

Session 13: Plasma 4

The Preliminary Program for International Thermal Spray Conference And Exposition (ITSC) (May 15-18, 2006)