超声塑化生热及其参数对温度特性的影响

Study on Heat Generation of Ultrasonic Plasticization and the Effect of Parameters on the Temperature Characteristics

超声熔融塑化注射成型是一种新型的聚合物塑化方式,而聚合物超声熔融塑化过程中温度场分布、超声波频率和振幅对聚合物塑化的影响规律等问题有待进一步的研究。本文针对这些问题,通过仿真计算、实验验证的方法,研究了超声工具头端面和外圆柱面振动对聚合物的熔融塑化效果和不同超声波参数对聚合物的熔融塑化的影响。结果表明:熔池从工具头端面中心部位开始形成,并向轴向和径向扩展;工具头轴向振动的塑化作用为聚合物熔融塑化的主要能量来源,其效果远远大于径向振动的塑化作用;超声波振幅对聚合物的塑化效率比超声波频率影响更大。

The ultrasonic plasticization was a new method for polymer plasticization. But there were many problems such as the polymer temperature distribution, ultrasound parameters （such as frequency, amplitude） which were the influencing factors in polymer plasticization. Simulation research was implemented to study the process of polymer ultrasonic plasticization, melting plasticization effect and effects of various ultrasonic factors on polymer melting plasticization. The results demonstrated that the effect of the portrait vibration of ultrasonic horn on the polymer plasticization was greater than that of the transverse vibration, which meant the primary energy source of polymer melting plasticization was the portrait vibration. The melting pool was firstly formed and expanded deep into the material, compared with the ultrasonic frequency, ultrasonic vibration amplitude contributed more to polymer heat generation.