Optimization of Mould and Part Structure for Spray-Free Metallic Plastics
Wu Luo, Yu Junbao, Fan Baolin, Yang Yadi
Orinko Advanced Plastic Co. Ltd., Hefei 231202, China
Abstract：For the problems of welding line and flow mark in the practical application of spray-free metallic plastics, the apparent defects were optimized and verified from the perspective of the mould and part structure. The results show that, simple structure design should be adopted for the structure of the parts, such as unnecessary rib, hole, wall thickness mutation and other structures should not be used as far as possible. Increasing the gate size can greatly reduce the flow mark and welding line, and the spoke gate is a better way. The using of rib and blind hole structure should be reduced as far as possible, if it cannot be avoided, the alignment and thickness arrangement should be adjusted appropriately according to the structure of the part. The orientation of rib should be vertical to the melt flow direction and the thinned (or hollowed out) treatment for the rib structure should be done as far as possible. When the wall thickness ratio of rib/part is controlled at <0.4, the apparent defects do not appear. The apparent defects at blind hole (or wall thickness change position) also decrease with the increase of wall thickness ratio of blind hole/part. The surface etching treatment has a good covering effect on the defects, and the effect of brushed finishing texture is better than that of grid texture.
Keywords：spray-free metallic plastic; welding line; flow mark; orientation of rib; wall thickness ratio; surface etch
Wu Luo，Yu Junbao，Fan Baolin，et al. Optimization of mould and part structure for spray-free metallic plastics[J]. Engineering Plastics Application，2020，48(10)：52-58.