Abstract: An additive friction stir deposition system for refractory metals is disclosed herein. The additive friction stir deposition system includes a tool assembly and an induction element. The tool assembly includes a metal shaft defining a shaft central channel, and a ceramic tip defining a tip central channel. The metal shaft and the ceramic tip are configured to interlock to prevent relative rotation therebetween. The induction element is positioned adjacent to the ceramic tip. As a refractory metal feedstock is fed through the shaft central channel and the tip central channel, the induction element heats the portion of the refractory metal feedstock within the tip central channel, but does not heat the ceramic tip itself. Accordingly, the refractory metal feedstock can be heated prior to application to a workpiece without heating the tip of the tool assembly, improving performance of the additive friction stir deposition system and the resulting workpiece.

Abstract: Disclosed herein is a kinetically deposited metal ring seal. In particular, disclosed herein is a joint assembly including a housing, a component, and a seal assembly. The housing defines an opening and a central axis. The component is positioned proximate the opening of the housing. The seal assembly comprises a kinetically deposited metal layer attaching the housing to the component and forming an airtight barrier around the central axis between the housing and the component. The kinetically deposited metal layer comprises a plurality of plasticized metal particles. Accordingly, the kinetically deposited metal layer can be applied at low temperatures, ensuring the temperature stays below the activation temperature of loaded fuel. Further, the kinetically deposited metal layer forms a low volume, airtight seal, which does not degrade over time, and does not require application of high forces to maintain the seal.

Abstract: An AM continuous welding system (AMCWS) is provided. The AMCWS includes a feedstock dispenser that configured to emit feedstock at a designated location, and a heat source configured to heat the feedstock. The AMCWS also includes a first eddy current sensor array that is configured to generate a first plurality of sensor signals while in current-sensing proximity of a re-solidified feedstock segment. A controller is coupled to the first eddy current sensor array and is configured to determine, based on the first plurality of sensor signals, a first characteristic of the re-solidified feedstock segment. The controller determines that the first characteristic is a first undesirable characteristic, and initiates an action based on the first undesirable characteristic.

Abstract: A powder bed sensing system and method is provided. A defect detection eddy current sensor array is configured to be movably coupled with respect to a powder bed, and generate a first plurality of sensor signals while moving over a workpiece in the powder bed. A workpiece edge detection eddy current sensor array is configured to be movably coupled with respect to the powder bed, and generates a second plurality of sensor signals while moving over the workpiece in the powder bed. A controller is coupled to the defect detection eddy current sensor array and the workpiece edge detection eddy current sensor array. The controller initiates an action based on at least one of a workpiece material layer quality and a workpiece edge location quality determined based on the first plurality of sensor signals and the second plurality of sensor signals.