Control of Typical Defects in Injection Molding of Thick-Walled Polycarbonate Products

被引：0

作者：

Wang B. ^{[1
]}

Wang T. ^{[1
]}

Ge Y. ^{[1
]}

Xiang N. ^{[1
]}

Sun Q. ^{[1
]}

Yan Y. ^{[1
]}

机构：

[1] Beijing Engineering Research Center of Advanced Structural Transparence for the Modern Traffic System, Beijing Institute of Aeronautical Materials, Beijing

来源：

Gaofenzi Cailiao Kexue Yu Gongcheng/Polymeric Materials Science and Engineering | 2020年 / 36卷 / 08期

关键词：

Apparent defects; Geometric shrinkage; Injection molding; Polycarbonate; Residual stress; Thick-walled structure;

D O I：

10.16865/j.cnki.1000-7555.2020.0188

中图分类号：

学科分类号：

摘要：

The influence of injection molding process on the typical defects (apparent defects, geometric shrinkage and residual stress) of polycarbonate (PC) prducts was investigated by the test method of single factor and multi-level, and the process conditions were as follows: mold temperature, injection speed, holding time, holding pressure and cooling time. The variation rules of different defects were analyzed according to the characterization of surface quality, shrinkage state and stress distribution. The results show that the vacuum bubbles in the apparent defects do not exist when the mold temperature is above 120℃, the holding time is 20 s, and the cooling time is 60 s, while the surface air streaks are completely eliminated when the injection speed is less than 5 mm/s. With the increase of holding pressure, holding time and mold temperature, the geometric shrinkage of the products decrease significantly, and the dimensional accuracy and geometric deformation are effectively controlled. The residual stress of the product is also affected by the forming process, but the effect of annealing is more obvious, which is also an effective mean to reduce the residual stress. © 2020, Editorial Board of Polymer Materials Science & Engineering. All right reserved.

引用

页码：130 / 137

页数：7

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