Seramik Enjeksiyon Kalıplama için İskelet Bağlayıcı Değişiminin Reolojik Özelliklerine Etkisi

Abstract

Toz enjeksiyon kalıplama prosesi için reoloji çalışması önemli bir yere sahiptir. Seçilen bağlayıcıların özellikleri; kalıplama, ön sinterleme ve sinterleme aşamalarını doğrudan ilgilendirmektedir. Besleme stokuna eklenen bağlayıcı özelliklerinin yanı sıra bağlayıcıların (ana bağlayıcı/iskelet bağlayıcı/yağlayıcı) kullanım amacı da önemlidir. Bu çalışmada seramik enjeksiyon kalıplama süreci için su bazlı ana bağlayıcı kullanılarak akış özellikleri (reoloji) belirlenmiştir. Reoloji deneyleri hem kılcal hemde tork reometreleri ile gerçekleştirilmiştir. Deneylerde; polietilen glikol ana bağlayıcı ve polipropilen/polietilen iskelet bağlayıcı kullanılarak farklı karışım oranlarında hazırlanan besleme stokları ile gerçekleştirilmiştir. Ana bağlayıcı değiştirilmeden (PEG4000), iskelet bağlayıcı olarak ise iki farklı (PP/PE) bağlayıcı kullanılmıştır. Buna bağlı olarak viskozite, kayma hızı, sıcaklık ve erime davranış indeksleri tespit edilmiştir. Deney sonucunda her iki besleme stoku için kritik toz yüklemesinin hacimce %56 oranında olduğu tespit edilmiştir.

Keywords

• Besleme Stoku
• Seramik Enjeksiyon Kalıplama
• Reoloji

Effect of Skeleton Binder Change on Rheological Properties for Ceramic Injection Molding

Abstract

Rheological characterization plays an important role in powder injection molding. Properties of the selected binders are related directly to the molding, pre-sintering and sintering stages. Besides the residual binding properties of the feedstock, the intended use of the binder (main binder/skeleton binder/lubricant) is also important. In this work, the flow properties of feedstock have been determined with the inclusion of a water-based main binder throughout the injection molding process of a studied ceramic composition. Rheology experiments have been carried out with both capillary and torque rheometers. In the experiments, polyethylene glycol main binder and polypropylene/polyethylene skeleton without changing the main binder (PEG4000), two different binders (PP / PE) were used as skeleton binders. Accordingly, viscosity, shear rate, temperature and melting behavior indexes were determined. In the experiment, it was determined that the critical powder volume concentration for both feedstocks was 56%.

Keywords

• Feedstock
• Ceramic Injection Molding
• Rheology

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