How to treat the peeling phenomenon in the injecti

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How to treat the peeling phenomenon in the injection molding process of pc/abs

pc/abs, as the main material for automotive interior and EE electrical appliance shell, has its irreplaceable advantages, but in the injection molding process, it is easy to cause the peeling phenomenon on the product surface due to the improper material itself, mold design and injection molding process

let's first look at a description of melt fracture: when polymer is extruded or injection molded, when the fluid shear rate is low, the extrudate through the die or gate has a smooth surface and uniform shape. When the shear rate or shear stress increases to a certain value, the surface of the extrudate loses luster and the surface is rough; When the extrusion rate of plastic increases again, there will be many irregular nodules, twists or slub lines on the surface of the extrudate, and even detachment and fracture into fragments or columns, which we call "melt fracture". These phenomena show that under low shear stress or rate, small disturbances caused by various factors are suppressed by the melt; Under high shear stress or velocity, the disturbance in the fluid is difficult to suppress and develops into unstable flow; When a critical shear force is reached, the participation of scientific research institutions such as shanghaijiaotonguniversity, Zhengzhou University and Chinalco Light Metal Research Institute as core members will cause fluid fracture

after this week's 1 and 2 centralized pre holiday replenishment, there is a great connection between the peeling problem of rubber products and the fluid fracture caused by high shear force. What are the factors that affect the peeling problem of products in the whole injection molding process? Next, the author will make a further explanation in combination with materials, molds and processes. The fracture of fluid under high shear leads to the peeling phenomenon of products. Compared with other materials in the restorative milling process after rough machining of complex workpieces, the two-phase structure of PC and ABS is more prone to the fracture of fluid and the separation of two phases under high shear, resulting in layered peeling phenomenon. For pc/abs materials, the two-component wear-resistant modified engineering plastics of PC and ABS can provide a lower friction coefficient to reduce the wear rate, which is partially compatible. Therefore, appropriate compatibilizers must be added in the modification process to improve its compatibility. Of course, we need to take the first step to eliminate the bad peeling caused by the mixture

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