PMMA双面滚压成型的数值模拟与验证实验

利用有限元软件ABAQUS,对聚甲基丙烯酸甲酯(PMMA)光扩散板双面滚压成型过程进行了数值模拟。通过建立PMMA的黏弹性模型,以微结构的复制率作为评价标准,利用数值模拟方法,分析了滚筒旋转速度、滚筒下压距离和PMMA基板温度对PMMA光扩散板两面不同形状微结构复制率的影响。结果表明,半圆形微结构复制率比等边三角形微结构复制率高;在一定范围内,复制率随着滚筒旋转速度的减小和滚筒下压距离的增大而增大,随PMMA基板温度升高而先增大后减小;当滚筒旋转速度为0.05rad/s,滚筒下压距离为0.45mm,PMMA基板温度为140℃时,半圆形和等边三角形微结构复制率均达到最大,分别为65.5%和51.2%。滚筒下压距离对复制率的影响最大,针对该参数进行实际滚压成型实验并将实验结果与仿真结果进行了对比验证,发现两者基本一致。

Numerical Simulation and Verification Experiment of Double-sided Roller Embossing of PMMA

A model of the double-sided roller embossing process of polymethyl methacrylate(PMMA)was simulated by using the finite element software ABAQUS.The viscoelastic material model of PMMA was established in the simulation and the replication rate of microstructure was used as the basis to judge,then detailed analysis was made to investigate the influences of various factors,such as rotation speed of roller,pressing distance of roller and PMMA substrate temperature,to the replication rates of microstructures with different shapes on both sides of PMMA light diffuser plate by numerical simulation.The results show that,the replication rate of semi-circular microstructure is higher than that of equilateral triangles microstructure.Under the certain conditions,the replication rate increases with the lower rotational speed and the greater pressing distance,first increases and then decreases with PMMA substrate temperature increasing.When the rotation speed is 0.05 rad/s,pressing distance is 0.45 mm and PMMA substrate temperature is 140℃,the replication rates of the semi-circular and equilateral triangles microstructure can reach the maximum,which are 65.5%and 51.2%respectively.Pressing distance is the most effective factor among the three parameters.So the practical doublesided roller embossing experiment for the pressing distance was done and the experiment results were compared with the simulation results.It is found that the two results are basically same.