机构地区: 浙江大学机械工程学系
出 处: 《浙江大学学报(工学版)》 2005年第12期1911-1914,共4页
摘 要: 针对聚合物热压过程中呈现出的黏弹性效应而导致不易直接建模问题,采用理论分析结合数值模拟的方法建立了热压过程的力学模型.分析了热压过程中的应力-应变分布与热压机的压力、聚合物的流动速率与应力及位置、聚合物的厚度随热压时间的变化关系.采用有限元方法(FEM)对热压过程进行了模拟,根据模拟结果对理论模型进行修正,获得了聚合材料常数n随时间的变化规律.数值模拟结果表明,该模型可以很好地描述出热压过程聚合物的力学行为,尤其是能够较好的反映出由于聚合物的黏弹性效应而呈现出的时间效应. To solve the difficulty of modeling the viscoelastic behavior of polymer in hot embossing process, the mechanical model in hot embossing was established by theoretical analysis and numerical simulation. The relationship of stress-strain distributing with the pressure of hot embossing machine, the flow rate of polymer with the stress and position, and the thickness of polymer with the time of hot embossing were analyzed. Finite element method (FEM) was used to simulate the hot embossing process. The theoretical model was corrected with the simulation data, and the rule of the polymer material's constant n changing with time was acquired. The numerical simulation results show that this model can describe well the polymeres mechanical behavior during hot embossing, especially effective in reflecting the time effect caused by polymer viscoelastic behavior.