Research on rheological properties and extrusion behavior of aqueous alumina paste in paste-extrusion-based SFF processes

摘要: In this work, the rheological properties and extrusion behavior of aqueous alumina paste which can be used in paste-extrusion-based solid freeform fabrication (SFF) processes are presented. According to analysis dynamic viscoelastic properties, with loading 50 vol% treated as a viscous–elastic–plastic body process. The shows feature before yielding viscoplastic after yielding. Although possesses shear-thinning behavior, it extruded steadily due relatively steady apparent viscosity within range shearing rate actual ram experiments show that variation pressure is essentially determined by paste. average stage estimated Benbow–Bridgwater model. However, there exists velocity threshold (0.1 mm/s study) below liquid phase migration will significant hardly estimated. Due fluid paste, extrudate cannot immediately reach expected value when starts stops, could result imprecise deposition “die drooling,” improved operation pulling back ram.