Comparison on Rheology Properties of Polypropylene and Polyethylene as Binder System with Stainless Steel 316L for Metal Injection Moding

摘要

The comparison of binder system between PP/ palm stearin and PE/ palm stearin both mixed with palm stearin were studied based on the rheological properties to (MIM) process. The microstructure of distribution and dispersion studied using scanning electron microscope (SEM) to observe the pattern of the attached binder with stainless steel powder. The types of binder system used were palm stearin with Polypropylene (PP) and Polyethylene (PE). The powder loading for stainless steel 316L with average size of 20um used was determined at 66 vol %. The palm stearin was the main significant factor for both viscosity and sensitivity of the feedstock behavior. Less content of palm stearin reduce the viscosity of the feedstock in the range of 100-10000 Pa.s and less influence on changing towards temperature and pressure. As the percentage of addition of palm stearin increase, the feedstock becomes less viscous with high sensitivity. PP and PE feedstock shows dilatant and pseudoplastic flow behavior respectively. PE homogenously coated each of stainless during morphology observation. Meanwhile poor distribution of PP can be observed from SEM observation at lOOOx magnification.