%0 Journal Article
%T Numerical analysis of flow-induced residual stresses in injection molding for polymer<br>聚合物注射成型流动残余应力的数值分析
%A Chen Jingbo Shen Changyu Liu Chuntai Wang Lixia
%A <br>陈静波
%A 申长雨
%A 刘春太
%A 王利霞
%J 力学学报
%D 2005
%I 
%X To simulate buildup and relaxation of flow-induced stresses and molecular orientation in injection molding process, a mathematical model is derived that describes the unsteady and non-isothermal flow of compressible viscoelastic polymer melts in the thin wall mold cavity on the base of thin film lubrication approximation. The compressible Leonov viscoelastic constitutive equation and Tait state equation are used in the model to describe the effects of compressibility of polymer melt which occur in the post-filling stage. The model is applied to the injection molding process which is treated in terms of a filling, post-filling and cooling stage and is solved using a finite difference method. Stresses calculated with the model are coupled to birefringence by means of the stress-optical rule. Birefrigence is used to characterize the molecular orientation. The final results are given in terms of residual stresses and associated birefringence in the molded part, as influenced by the processing conditions. The result indicates that, for a given polymer, the main factors affecting flow-induced residual stresses and associated birefringence are flow rate and melt temperature, and with the incompressible case flow-induced residual stresses and associated birefringence are increased when the compressibility of the melt is considered. The result are compared with the birfriengence measurement in the literature and reasonable agreement is obtained.
%K injection molding
%K viscoelastic flow
%K frozen in orientation
%K residual stresses
%K numerical simulation<br>数值分析
%K 残余应力
%K 注射成型过程
%K 聚合物熔体
%K 非稳态流动
%K 保压过程
%K 数学模型
%K 松弛过程
%K 数值方法
%K 熔体温度
%K 工艺条件
%K 注射速率
%K 模具温度
%K 非等温
%K 黏弹性
%K 可压缩
%K 应力和
%K 取向
%K 分子
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=6E709DC38FA1D09A4B578DD0906875B5B44D4D294832BB8E&cid=5D344E2AD54D14F8&jid=4100DA4A1A3BA1B0CE5AD99AE1DFB420&aid=DB3CA80C416B240C&yid=2DD7160C83D0ACED&vid=42425781F0B1C26E&iid=38B194292C032A66&sid=4E6F5C60B72D9B1C&eid=69E4C201C13601F9&journal_id=0459-1879&journal_name=力学学报&referenced_num=4&reference_num=9