热塑性塑料超声波焊接的热力过程数值模拟  

Numerical simulation of thermal and mechanical process during ultrasonic welding of thermoplastic

作　　者：严波[1,2] 丁浩亮[3] YAN Bo;DING Hao-liang(National Engineering Research Center of Die&Mold CAD,Shanghai Jiao Tong University,Shanghai 200030,China;School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 200030,China;Aerospace Research Institute of Materials&Processing Technology,Beijing 100076,China)

机构地区：[1]上海交通大学模具CAD国家工程研究中心,上海200030 [2]上海交通大学材料科学与工程学院,上海200030 [3]航天材料及工艺研究所,北京100076

出　　处：《塑性工程学报》2020年第5期33-40,共8页Journal of Plasticity Engineering

基　　金：国家重点研发计划资助项目(2018YFB1106700);国家自然科学基金资助项目(51005151)。

摘　　要：在建立热塑性塑料的粘弹性力学模型和传热模型的基础上,根据应力和粘度模型计算粘弹性热能可以准确地计算粘弹性热。通过开发超声波塑料焊接的有限元数值模拟程序研究了焊接瞬间的热力行为,数值模拟结果表明,平板件焊接时受压区域整体温度有不同程度的升高,焊接首先发生在焊接面的外围区域,平板件焊接实验验证了数值模拟的准确性。数值算例还研究了初始温度、焊接压力、超声波频率和超声波振幅等焊接工艺参数对焊接过程的影响,有效的焊接必须高于临界初始温度,提高超声波频率和振幅可显著提高温度升高的速度与幅度。Based on the establishment of the viscoelastic mechanics model and heat transfer model for thermoplastic,the viscoelastic dissipation can be calculated correctly according to the stress and viscosity formulae. A numerical simulation of finite element method( FEM) program was developed to simulate the evolution of viscoelastic mechanics and heat transfer during ultrasonic welding. Numerical simulation results show that the temperature increases to different extent in whole field under pressure when flat energy direction is used and the welding takes place firstly in the periphery area which is verified by the experimental phenomenon. Other numerical examples were conducted to investigate the effect of initial temperature,holding pressure,ultrasonic frequency and amplitude on heat transfer and thus welding quality during ultrasonic welding. The initial temperature must be larger than the critical initial temperature to achieve valid ultrasonic welding. In addition,the temperature of welding part can be increased more quickly and higher if higher ultrasonic frequency and amplitude are used.

关 键 词：热塑性塑料 超声波焊接 粘弹性热 平板件焊接 数值模拟 

分 类 号：TQ320.6[化学工程—合成树脂塑料工业]