Hypervelocity Powder Deposition using Pulsed Power Magnetic Flux Compression Devices

This paper outlines two original concepts which, in combination, can bring fundamental advances to both manufacturing and materials technologies and the pulsed power approach to them, and describes a laboratory system already built which has conducted proof-of-principle experiments. The first novel concept uses a hypervelocity accelerator for a new thermal spray process using electromagnetic forces to accelerate powder particles to velocities of 2 km/s or higher, more than twice that of the powder velocities of about 1 km/s used by the existing state-of-the-art thermal spray processes (HVOF, D-gun, plasma spray) which are limited by their reliance on the thermodynamic expansion of gases. The second original concept is a pulsed power supply, a new electrical machine-flux compressor with precisely controllable output capable of matching ideally the powder spraying hypervelocity accelerator at any moment of time. Due to the compensation systems, the compulsators are low internal impedance machines designed for pulsed duty and capable of providing large current pulses, with a rapid rise time (in our case, less than 25 /spl mu/s to 80 MW pulsed power) to a low impedance load-a hypervelocity square bore railgun accelerator (SBA) assuring an almost continuous process. After describing the results of some experiments confirming system modeling and performance, the paper concludes with future directions of this research.