摘要
针对金属质感免喷涂改性塑料在实际应用过程中常存在的熔接线及流痕问题,从注塑工艺角度对免喷涂金属质感改性塑料表观缺陷进行了优化验证研究。结果表明,提升注塑温度、降低注塑速度对流痕和熔接线有改善作用,但同时要兼顾低速注塑条件下易出现的欠注风险,对于复杂结构制件要注重分段多级注塑的验证;提高模具温度可以大大减弱流痕和熔接线,其中模具急冷急热技术是较好的改善手段;对于孔洞结构,常规的加工工艺改善措施对流痕及熔接线只有一定的缓解作用,无法根除,而模内切技术以其独特的加工过程,能实现孔洞结构流痕和熔接线的完美消除,是孔洞结构缺陷解决的有力方案;应尽量减少模具浇口的数量,如果无法规避,应根据制件结构适当调整浇口排布,通过顺序进胶方式将流痕和熔接线规避或是赶至制件非外观面。
In order to solve the problems of weld line and flow mark in the practical application of spray-free metallic plastics,the apparent defects were optimized and verified from the perspective of injection molding technology.The results show that improving injection temperature and reducing injection speed have improvement effects on weld line and flow mark,but at the same time,the risk of short shot is easy to occur under the condition of low speed injection molding.It is necessary to pay attention to the verification of multistage injection molding for complex structural parts.Increasing the mould temperature can greatly reduce the flow mark and weld line,and the mould quick cooling and heating technology is a better way.For the hole structure,the conventional process improvement measures can only alleviate the convective marks and weld line,but cannot be eradicated.However,with its unique processing process,the in-die cutting technology can realize the perfect elimination of the flow mark and weld line of the hole structure,which is a powerful solution for the defects of the hole structure.The number of die sprue should be reduced as far as possible.If it cannot be avoided,the sprue arrangement should be adjusted appropriately according to the structure of the workpiece,and the flow mark and weld line should be avoided or rushed to the non-external surface of the workpiece by means of sequential glue feeding.
作者
吴摞
余俊宝
杨亚娣
Wu Luo;Yu Junbao;Yang Yadi(Orinko Advanced Plastic Co.,Ltd.,Hefei 231202,China)
出处
《工程塑料应用》
CAS
CSCD
北大核心
2020年第8期71-76,86,共7页
Engineering Plastics Application
关键词
免喷涂金属质感塑料
熔接线
流痕
低剪切
膜内切
顺序进胶
spray-free metallic plastics
welding line
flow mark
low shear force
in-die cutting
sequential injection
