Fabrication of Micro Structure with Complicated Shape by Temperature Controlled Semi-solid Mold Isostatic Powder Compaction

Abstract

New powder compaction process using a Bingham semi-solid/fluid mold was developed to fabricate micro parts. In the present work, a powder material was filled as slurry in a solid wax mold, dried and compressed by conventional pressing methods, such as isostatic pressing or die compaction. It is important to use slurry for filling because dry powder is hard to fill in the micro cavity. It is also essential to control the process temperature to treat micro parts. The wax mold was heated during compaction and became semi-solid state, which could acts as a pressurized medium for isostatic compaction. Since the compacted micro parts were very fragile, the mold's temperature was controlled to higher than its melting point during unloading, to avoid breakage of the compacts. To demonstrate effectiveness of the present process, some micro compacts of alumina are shown as examples.