Novel Current-Activated Tip-based Sintering (CATS)

The research objective of this award is to investigate a novel manufacturing process that allows the controlled 'localized' sintering of micro-scale and nano-scale features and devices from powders. The process, named Current-Activated Tip-based Sintering (CATS), uses a micro or nano conductive tip to simultaneously apply electric current and controlled contacting pressure to the surface of a powder bed. The path of the tip is controlled to sinter/consolidate simple or complex geometries. The present study is designed to answer a number of fundamental scientific questions for this process and will be addressed through both experimental and modeling efforts. The influence of process variables including current density, current form, tip speed and powder green density/packing on the characteristics of the area of influence beneath the tip (process zone) and sintering behavior will be studied. If successful, the approach can be adopted for 1D, 2D and 3D micro and nano-scale powder-based fabrication. Advantages of the process also include ultra-rapid heating and sintering rates un-attainable by conventional sintering, and a process zone that should be attained even on the nano-scale. The study will offer important insights into the underlying mechanisms responsible for the localized current-activated 'tip-based' sintering behavior. The approach can be applied to a very wide range of materials, including metals, intermetallics, shape memory alloys, porous materials and composites. This technology would have wide spread applications within a number of industries, including micro/nano-sensors and actuators, micro/nano-filters and micro-electro-mechanical systems (MEMS).