开口结构件因开口位置两侧结构缺少支撑,而易在注射成型时翘曲变形,导致严重的形状精度超差现象。通过测量不同时刻的零件翘曲变形量与拐角温度,获得了某厚壁开口结构件的翘曲变形变化数据。基于Moldflow平台构建出其注塑成型过程的数...开口结构件因开口位置两侧结构缺少支撑,而易在注射成型时翘曲变形,导致严重的形状精度超差现象。通过测量不同时刻的零件翘曲变形量与拐角温度,获得了某厚壁开口结构件的翘曲变形变化数据。基于Moldflow平台构建出其注塑成型过程的数值模型,利用高压毛细管流变仪对其材料的黏度进行了测量,通过Moldflow Data Fitting拟合出该材料的Cross-WLF黏度模型系数,并结合实测数据对模型进行修正。基于所构建的修正模型及测量数据,对注塑过程的压力状态和温度状态进行了研究,最后通过正交试验对翘曲变形量的影响因素进行了极差分析,并进行了试验验证。展开更多
Difference of offset spinning with conventional symmetric spinning is analyzed. A 3D FEM model for offset tube neck-spinning is established and the spinning process is simulated by means of ANSYS software. Dynamic bou...Difference of offset spinning with conventional symmetric spinning is analyzed. A 3D FEM model for offset tube neck-spinning is established and the spinning process is simulated by means of ANSYS software. Dynamic boundary and contact problems in simulation are solved. Transient stress distribution of contact area, transient strain distribution of nodes in typical section and strain distribution of the workpiece at last are attained, the place and the cause of crack are analyzed. Strain variation curves with time of offset spinning and conventional spinning are compared. It shows the mechanism difference between offset spinning and conventional spinning. In addition, simulation results show how strain distribution of typical section, thickness of some typical nodes, axial extension in left section and force of three rollers change with time. According to the study of the variation curve, material flow law along radial, tangential and axial direction is attained and the whole spinning process is studied. The simulation results discover that offset distance is the key to manufacture offset non-symmetric tube, and process parameters change with spinning angle. Experiment data really reflect different process parameters＇ influence on conventional symmetric and offset spinning force. Experiments accord well with simulation.展开更多
文摘开口结构件因开口位置两侧结构缺少支撑,而易在注射成型时翘曲变形,导致严重的形状精度超差现象。通过测量不同时刻的零件翘曲变形量与拐角温度,获得了某厚壁开口结构件的翘曲变形变化数据。基于Moldflow平台构建出其注塑成型过程的数值模型,利用高压毛细管流变仪对其材料的黏度进行了测量,通过Moldflow Data Fitting拟合出该材料的Cross-WLF黏度模型系数,并结合实测数据对模型进行修正。基于所构建的修正模型及测量数据,对注塑过程的压力状态和温度状态进行了研究,最后通过正交试验对翘曲变形量的影响因素进行了极差分析,并进行了试验验证。
基金This project is supported by National Natural Science Foundation of China (No.50275054)Provincial Natural Science Foundation of Guangdong, China (No.020923)Provincial Science and Technology Key Project of Industry of Guangdong, China(No.2003C102013)High Level Construction Project of South China University of Technology, China(No.73056060).
文摘Difference of offset spinning with conventional symmetric spinning is analyzed. A 3D FEM model for offset tube neck-spinning is established and the spinning process is simulated by means of ANSYS software. Dynamic boundary and contact problems in simulation are solved. Transient stress distribution of contact area, transient strain distribution of nodes in typical section and strain distribution of the workpiece at last are attained, the place and the cause of crack are analyzed. Strain variation curves with time of offset spinning and conventional spinning are compared. It shows the mechanism difference between offset spinning and conventional spinning. In addition, simulation results show how strain distribution of typical section, thickness of some typical nodes, axial extension in left section and force of three rollers change with time. According to the study of the variation curve, material flow law along radial, tangential and axial direction is attained and the whole spinning process is studied. The simulation results discover that offset distance is the key to manufacture offset non-symmetric tube, and process parameters change with spinning angle. Experiment data really reflect different process parameters＇ influence on conventional symmetric and offset spinning force. Experiments accord well with simulation.
