水基ZrB_2膏体的挤出流变行为研究  

Research on Rheological Behavior during Extrusion of Aqueous ZrB_2 Paste

作　　者：刘洪军[1] 李冬健[1] 刘佳[1] 

机构地区：[1]兰州理工大学,兰州730050

出　　处：《中国陶瓷》2013年第7期24-27,37,共5页China Ceramics

基　　金：国家自然科学基金项目(50906037);甘肃省国际科技合作项目(1011WCGA163)

摘　　要：研究了用于Freeze-form Extrusion Fabrication工艺的水基ZrB2膏体的挤出流变性能。动态力学分析表明该膏体可以作为粘弹塑性体来处理:在挤出过程中,屈服前表现为粘弹性固体特性,屈服后表现为粘塑性流体特性。虽然有剪切变稀现象,但在实际的挤出工艺范围内表观粘度变化平稳,水基ZrB2膏体可稳定挤出,并可用宾汉体流体进行描述。挤出实验表明:挤出速度高于0.1 mm/s时不发生液相迁移现象,可以用Benbow-Bridgwater模型来预测挤出压力和挤出参数的关系。The rheological behavior during extrusion of aqueous ZrB2 paste for Freeze-form Extrusion Fabrication process was investigated in this paper. The dynamic mechanical analysis shows that the paste can be treated as visco-elastoplastic material. The paste shows the characteristic of viscoelastical solid during the pre-yield stage and viscoplastic fluid during the post-yield stage. Although the paste has shear-thirming property, the apparent viscosity is rel-atively steady in the actual extrusion flow rate range, so the paste can be steadily extruded and can be described as Bingham fluid. The extrusion experimentations show that： the liquid phase migration phenomena will appear when the extrusion velocity is higher than 0.1 ram/s, and the relation between of extrusion pressure and extrusion parameters can be predicted by Benbow-Bridgwater model.

关 键 词：水基ZrB2膏体 挤出 流变行为 粘弹塑性体 液相迁移 

分 类 号：TQ174.12[化学工程—陶瓷工业]