Analysis of the Rheological Behavior and Stability of Inconel 718 Powder Injection Molding (PIM) Feedstock

Abstract:

In PIM process, the molding stage is a critical step for the fabrication of sound parts without cracks and distortions. So, this step requires specific rheological behavior. Rheological analysis can be made to quantify the stability of the PIM feedstock during molding process. In this study, an experimental rheological study has been performed to evaluate the influence of palm stearin on the rheological behavior and stability of Inconel 718 powder injection molding (PIM) feedstock. The effects of shear rate and temperature were investigated via capillary rheometer method. The viscosity and shear rate of the feedstock were measured at various range of temperature and shear rate across the L/D = 1 capillary rheometer. The results show that the formulation binder system PSPE 7030 is the best feedstock to be injection molded because it has moderate value of flow sensitivity index, lower value for flow activation energy and higher value for mold ability index. Besides that, the increasing of PS content in the binder system has found reduce viscosity and value of flow activation energy and increase value of mold ability index of feedstock.

• Periodical: Advanced Materials Research (Volume 879)
• Pages: 63-72
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.879.63
• Online since: January 2014
• Authors: Ahmad Nizam bin Abdullah, Nurhaslina binti Johari, Muhammad Jabir bin Suleiman Ahmad, Rosdi Ibrahim, Abdul Rahim Abu Talib
• Keywords: Inconel 718, Mold Ability Index, Palm stearin, Powder Injection Molding, Rheological Behavior

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