材料期刊网

分析与探讨了高温玻璃的应力流动模型及其材料参数的温度相关性。利用粘刚塑性力学模型，基于三维有限元软件DEFORM 3D建立非球面透镜高温模压有限元模型，对光学玻璃L-BAL42球形预制件模压成非球面透镜的整个过程进行了数值仿真，发现非球面透镜应力分布规律：透镜边缘处应力最大，在和模阶段应力快速增加，导致透镜边缘处最易破碎，结果得到实验的验证。采用较大的模压速度及冷却速度将导致残余应力增加，同时分析了透镜非球面偏差变化规律。最后在模具设计时将非球面偏差补偿进去，发现非球面透镜偏差减少，由正偏差变为负偏差。

The temperature dependence of flow stress model and glass material parameters at high temperature was analyzed and discussed. The three?dimensional finite element model of compression molding of aspheric lens at high temperature was established using viscous?rigid model based on DEFORM 3D. The whole process of optical glass spherical L?BAL42 preform being molded into aspheric lens was studied by numerical simulation. It is found that maximum stress is at lens edge and stresses increase rapidly when mold is closed,leading to the lens edge most easily being broken,the result is validated by experiments. Residual stress will increase with increasing compression rate and the cooling rate,and the rules of aspheric lens deviation were analyzed. Finally aspheric surface deviation was compensated during the mold design stage. It is found that the aspheric surface deviation will decrease,deviation changes from positive to negative.