聚碳酸酯板材多点热成形数值模拟与成形精度分析

提出了用于热塑性聚合物板材的柔性成形技术——多点热成形技术。根据高温单向拉伸试验数据确定了不同温度下聚碳酸酯（PC）板材的超弹性材料模型参数。运用有限元软件Abaqus对不同温度和不同成形压力下的PC板材多点热成形过程进行了数值模拟，结果表明：当成形温度与成形压力分别为160℃和10kPa时，成形件平均形状误差最小。参照数值模拟结果进行了PC板材的多点热成形试验，验证了数值模拟结果的准确性。测量并分析了成形件的成形精度，结果表明：成形件具有较高的成形精度，可以满足工程应用需要。

A new flexible forming technique for thermoplastic polymer: multi-point thermoforming (MPTF) was developed. Polycarbonate (PC) is a typical thermoplastic polymer exhibiting many properties ideally. The material parameters of PC according to Mooney-Rivlin hyperelastic constitutive model were determined based on the high temperature tensile test data. The commercial software Abaqus was utilized to simulate the MPTF process of PC sheet. A series of numerical simulation results show that the best combination of forming temperature and forming pressure for PC sheet are 160°C and 10 kPa, respectively. MPTF experiments were carried out under the processing parameters which were determined by numerical simulations and the simulation results were validated by comparing them with the experimental results. The spherical and saddle-shape parts formed by MPTF were measured using a 3D sensing system and the measured data were compared with the target shape to analysis the accuracy of MPTF. The comparison results show that the formed parts have good accuracy.