激光加工聚合物微流控芯片暂态烧蚀模型研究

为了预测激光直写加工聚合物微流控芯片三维微流道外形，提出了三维烧蚀加工的解析模型.在CO2激光加工聚合物原理基础上，根据传热学原理和烧蚀面能量守恒原理，建立了激光加工三维暂态烧蚀模型.根据在微元控制面上热传导只发生在表面法向，并且激光加工在瞬时达到准稳态，将三维暂态偏微分方程转化为一维常微分方程.基于烧蚀面上的温度始终保持为降解温度，求出关于激光功率、扫描速度和材料热物理系数的微流道外形函数解，并用聚甲基丙烯酸甲酯进行了实验验证.实验结果表明，由解析模型得到的理论值与实验数据吻合很好，该模型的理论推导是符合实际加工实践的.

Transient ablation model for laser machining polymer microfluidic chip

To predict the three-dimensional groove shape made by laser direct-writing polymer microfluidic chip,a three-dimensional analytical model of ablation machining was established.Based on the principles of CO_2 laser machining polymer,heat conduction theory and energy conservation principal at the ablation front,a three-dimensional transient ablation model of laser machining was built.According to the heat conduction spreading only in the direction of local surface normal on infinitesimal control surface and laser machining reaching steady state instantaneously,a three-dimensional transient partial differential equation was translated into a one-dimensional constant differential equation.Groove shape function of laser power,scanning velocity and materials' thermo-physical coefficients was solved due to temperature at ablation front keeping decomposed temperature, and the proposed model was tested in polymethylmethacrylate experiment.The results indicate that the theoretical data derived from the analytical model agree well with the experimental data,and that the proposed model is suitable for machining practice.