成形品へ及ぼすノズル通過樹脂温度挙動の影響
Influence of the Injected Resin Temperature Behavior through the Nozzle on Moldings
西脇信彦・今野政昭・崔 愛玲・橋本展明・堀 三計
Nishiwaki, Nobuhiko / Konno, Masaaki / Cui, Ailing / Hashimoto, Nobuaki / Hori, Sankei
When crystalline thermoplastic is used as an injected material, the crystallinity of the moldings depends on the cooling rate of the resin in the cavity. Therefore, a number of CAE software packages for simulating the cooling behavior of the filled resin have been developed, by assuming constant temperature of the resin through the nozzle. On the other hand, it is clear that the temperature of the resin injected from the nozzle into the cavity is not always constant. Moreover, the influence of the temperature variation of the injected resin on the crystallinity distribution in the moldings has not also been made clear.
In this paper, the temperature behavior of the resin injected into the cavity was related to the barrel temperature distribution and nozzle temperature. It is clear that the crystallinity distribution of the molded resin depends on the temperature behavior of the injected resin. From these experimental results, it is clear that the crystallinity distribution of the molded resin becomes nearly constant when the injected resin temperature through the nozzle is high at the initial injection stage, and becomes low after the initial stage.
Key words: Injected resin temperature / Cooling behavior / Crystallinity distribution