Sedef ÇAKIR, Muhammet AYÇİÇEK, Neslihan ÖZSOY, Murat ÖZSOY, Mert USTA, Akın AKINCI

Toyota CH-R SUV Kapı Paneli Üretiminde Ağırlığı ve Enjeksiyon Kalıplama Çevrim Süresini Azaltmada Polipropilen Köpük Kullanımı

Son yıllarda doğal hammadde kaynaklarının tüketilmesi sonucu hammadde maliyetlerindeki artış ve çevre bilincinin oluşması ile ucuz ve daha az hammadde kullanımını teşvik eden yeni teknolojiler otomotiv endüstrisinde ön plana çıkmaktadır. Bu çalışmada Toyota CH-R model arabanın kapı paneli üretiminde köpük kullanılarak kapı panelinin hafifletilmesi ve enjeksiyon çevrim süresinin kısaltılması amaçlanmıştır. Silindir orta sıcaklığı, enjeksiyon hızı, enjeksiyon geri basıncı, tutma basıncı ve tutma süresi gibi enjeksiyon parametreleri üzerinde değişiklikler yapılmıştır. Polipropilen (PP) matrise ağırlıkça %1, %1,5 ve %2 oranında kimyasal köpük ajanı (KKA) ilave edilmiştir. Köpük ajanı kullanımı sonucu ağırlıkta yaklaşık olarak %4 hafiflik ve enjeksiyon çevrim süresinde ise 5,5 s düşüş sağlanmıştır. Aynı zamanda hücre morfolojilerinin, mekanik özellikler ve numune ağırlıkları; proses parametreleri ile ağırlıkça CFA oranındaki değişime bağlı olarak farklılık gösterdiği gözlenmiştir.

Anahtar Kelimeler:

hücre morfolojisi, kimyasal köpük ajanı, enjeksiyon kalıplama, hafif malzeme, polimer köpük

Using Foamed Polypropylene to Reduce Weight and Injection Molding Cycle Time in Toyota CH-R SUV Door Panel Production

In recent years, new technologies that encourage the use of cheaper and less raw materials have emerged in the automotive industry, with the increase in raw material costs as a result of the consumption of natural raw material resources and the occurrence of environmental problems. In this study, it was aimed to lighten the door panel and reduce the injection cycle time by using foam in the door panel production of Toyota CH-R model car. Injection parameters such as barrel temperature, injection speed, injection back pressure, holding pressure and holding time were changed. 1%, 1.5% and 2% by weight chemical foaming agent (CFA) was added to the polypropylene (PP) matrix. Approximately 4% lightening and 5.5 sec/shot injection cycle time reduction was achieved with the use of foaming agents. In addition, it was observed that cell morphologies, mechanical properties and sample weights changed due to changes in parameters and CFA ratio by weight.

Keywords:

cell morphology, chemical foaming agent, injection molding, light weight material, polymer foam,

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