|Fine Ceramic Components for Electronic Application
Goal: To develop the process and machine capability for printing of fine featured ceramic parts for electronic applications. Ceramics of interest include alumina and barrium titanate and applications include RF filters, and a range of passive and active devices. In many cases, metal electrodes will be printed integral to the device. 3D Printing has the potential to make devices which cannot be fabricated by other methods such as dry pressing or screen printing due primarily to greater flexibility in geometry.
Approach: The process technology component is directed at advancing our ability to process fine ceramic powders with 3D Printing. Fine powders are processed using the slurry deposition method. A slurry of powder is jetted through a nozzle which is raster-scanned over the surface of the powderbed in order to meter out a precise layer of fine powder. The wet layer is dried and then binder is ink-jet printed into the layer. (Wet deposition of the layer is required when fine powder is used as fine powder cannot be easily spread in the dry condition.) This program has led to advances in the basic understanding of critical aspects of this processing including the ability to fabricate thin layers of powder without cracks, the ability to bind the powder and the ability to re-disperse the powder around the part where no binder has been printed (the part must be retrieved from a "brick" of fine powder). The result has been the ability to print parts with sub-mm features.
The machine technology developed under this program has pioneered a second class of 3D Printing manufacturing machine - directed at the manufacture of many copies of small, fine featured components. The machine architecture under development takes advantage of the fact that these small, precision parts are fabricated in small, light powderbeds. Thus, a machine can be designed where the powderbeds move to the various stations (powderbed deposition, drying, printing), rather than having the stations move to the powderbed. This allows for a "rotary" style machine where all stations can be in use simultaneously. Further, the small size of the parts allows for the use of a vector motion of the printhead to define the outline of the part - so as to make the surface finish as good as possible. Individual, drop-on-demand nozzles will be used to described the parts, one nozzle per part. All nozzles will move simultaneously and describe the same contour, each defining its own part! . In this manner, if a single nozzle fails, one part will be lost and the other parts will be unaffected.
Sponsor: TDK Corp. of America
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