Near Net Shape Forming of ALON Hemispherical Domes

The current method for producing dome blanks for multimode optics involves pressing powders around metal mandrels using isostatic pressure. Yield losses during powder preparation, and excess material requirements in the pressing step represent a significant portion of the final part cost. An alternative means for fabricating ceramic materials from powders has been identified and a strategy to modify it to facilitate dome formation by incorporating technology used commercially in the metal and polymer forming industries has been determined. This method merges the advantages of dry powder formation processes with improved powder yield, reduced opportunity for heterogeneities in the formed product and the opportunity for high throughput. We propose herein to investigate this alternative fabrication method to determine its suitability for ALONtm dome fabrication. Evaluation of process capability and resulting material quality will be made on both flats and domelet samples. An initial trade evaluation will be made between these developing methods, compared to standard isopressing, and wet processing techniques currently under development in other programs.