超声辅助微注塑成型中熔体壁面滑移行为的研究  

Study on Wall Slip Behavior of Polymer Melt in Ultrasonic-Assisted Micro-Injection Molding

作　　者：高山 仇中军[1] 马壮 

机构地区：[1]天津大学精密测试技术及仪器国家重点实验室,天津300072

出　　处：《应用基础与工程科学学报》2017年第5期1057-1064,共8页Journal of Basic Science and Engineering

基　　金：国家自然科学基金项目(51375336;50905125);天津市自然科学基金重点项目(12JCZDJC27900)

摘　　要：壁面滑移在聚合物熔体注塑成型过程对熔体充模流动行为具有显著的影响.本文基于对超声辅助微注塑加工机理的研究,分析了超声振动对微尺度型腔中熔体壁面滑移的作用方式.结合聚合物熔体壁面滑移方程和超声对熔体壁面滑移的影响机理,阐明了不同情况下的壁面滑移理论模型.采用毛细管流变仪研究了超声振动作用下的聚合物熔体的壁面滑移行为,通过分析壁面滑移的临界剪切应力变化,明确了超声振动作用下的熔体壁面滑移行为对微尺度型腔充模情况的影响.研究结果表明,超声辅助微注塑过程中,超声作用下的微尺度型腔中熔体壁面滑移的临界剪切应力降低或变为零,壁面滑移速度随剪切应力增加而增加,不同剪切速率时超声作用下的熔体黏度均明显降低,进而提升了熔体对微尺度型腔的充模能力并改善了微塑件的成型质量.The action of ultrasonic vibration on the polymer melt wall slip during the ultrasonic- assisted micro-injection molding process was analyzed based on the study of the mechanism of this method. The theoretical model of wall slip under ultrasonic vibration during the process was expounded by comprehensive considering the wall slip equation of polymer melt and the influence mechanism of ultrasonic vibration on the melt. The wall slip behavior of melt and the change of the critical shear stress were＇ demonstrated by the use of a capillary rheometer with the ultrasonic vibration generator, subsequently the influence of melt slip behavior under the effect of ultrasonic vibration on the filling quality of micro cavity was discussed. The results showed that during the ultrasonic-assisted micro-injection molding process, critical shear stress of melt in micro cavity under the action of ultrasonic decreased or became zero, the melt viscosity under ultrasonic vibration was reduced, thereby the melt filling capability in micro cavity was enhanced and the molding quality of micro plastic parts could be improved.

关 键 词：超声 微注塑 壁面滑移 熔体流动 毛细管流变仪 

分 类 号：TB55[理学—物理]