Thompson, Chad 1984- (2012-12). A Rotating Electrode System for the Generation of Metal Alloy Microspheres. Master's Thesis. Thesis uri icon

abstract

  • TerraPower LLC is designing a fast breed and burn reactor intended to operate for up to 40 years without refueling, designated as the Travelling Wave Reactor (TWR). Various U-Zr alloy fuel designs have been proposed for the TWR that may require a powder feed for fabrication. A simple and economic option for laboratory scale powder production is the Rotating Electrode Process (REP), which produces microsphere shaped powder by melting the tip of a rotating bar with an electric arc. In order to fully characterize this process for various U-Zr alloys and provide the feed material for testing fabrication techniques, a Rotating Electrode System (RES) was designed and built. The RES is largely based on a combination of two designs; an early REP system developed by Starmet Corporation in the 19xxa and a later design optimized for U-Mo powder production by Idaho National Laboratory (INL). The RES designed for this work was improved based on input from vendors specializing in their respective areas of expertise and is capable of atomizing up to a 1.26 cm diameter metal alloy rod at 40,000 RPM. Every component of the machine can be disassembled and transferred through a 35.56 cm (14 in) diameter air lock of a glovebox so that it can operate in a controlled environment. The RES was tested by atomizing various diameter copper rods to prove system functionality. The tests were carried out in air using an argon cover gas in the powder collection chamber, known as the catch pan to limit oxidation rates of the newly generated microspheres. The powder produced showed strong sphericity ranging from 50 um to 500 um in diameter. Problems and areas of concern that were encountered during operation have been addressed so that the RES can be further optimized to better atomize U-Zr alloys once transferred into the glovebox.
  • TerraPower LLC is designing a fast breed and burn reactor intended to operate for up to 40 years without refueling, designated as the Travelling Wave Reactor (TWR). Various U-Zr alloy fuel designs have been proposed for the TWR that may require a powder feed for fabrication. A simple and economic option for laboratory scale powder production is the Rotating Electrode Process (REP), which produces microsphere shaped powder by melting the tip of a rotating bar with an electric arc. In order to fully characterize this process for various U-Zr alloys and provide the feed material for testing fabrication techniques, a Rotating Electrode System (RES) was designed and built.

    The RES is largely based on a combination of two designs; an early REP system developed by Starmet Corporation in the 19xxa and a later design optimized for U-Mo powder production by Idaho National Laboratory (INL). The RES designed for this work was improved based on input from vendors specializing in their respective areas of expertise and is capable of atomizing up to a 1.26 cm diameter metal alloy rod at 40,000 RPM. Every component of the machine can be disassembled and transferred through a 35.56 cm (14 in) diameter air lock of a glovebox so that it can operate in a controlled environment.

    The RES was tested by atomizing various diameter copper rods to prove system functionality. The tests were carried out in air using an argon cover gas in the powder collection chamber, known as the catch pan to limit oxidation rates of the newly generated microspheres. The powder produced showed strong sphericity ranging from 50 um to 500 um in diameter. Problems and areas of concern that were encountered during operation have been addressed so that the RES can be further optimized to better atomize U-Zr alloys once transferred into the glovebox.

publication date

  • December 2012