Optimizing Rheological Behavior of Steel Feedstocks in Advanced Process of Alloying Powder Injection Molding

Subject Areas : Smart & Advanced Materials

حمید  خورسند ¹ (Assistant Professor, Faculty of Mechanical Engineering, K. N. Toosi University of Technology, Tehran, Iran)
مژده  فتحی دوست ² (M.Sc., Faculty of Mechanical Engineering, K. N. Toosi University of Technology, Tehran, Iran)

Received: 2015-06-07 Accepted : 2015-06-07 Published : 2012-11-01

Keywords: Viscosity, Metal Injection Molding, Powder Loading, Feedstock, rheological behavior,

Abstract :

The rheological behavior of feedstocks used in powder injection molding technology influences strongly on the final properties of the products. Powder loading is one of the important factors that have a great distribution on rheological behaviors. By using the gas atomized spherical 316L stainless steel powder and the binder of 55% paraffin wax+ 40% polyethylen+ 5% stearic acid, four kinds of feedstocks were prepared at the powder loading of 60, 64, 68 and 72%. To find the proper feedstock and molding temperature, the applied shear rate on the samples has been increased from 100 to 1000 l/s in three different temperatures. The investigations demonstrate that 68% powder loading is the optimal one. This sample shows the minimum sensitivity to shear rate and temperature and in a wide range of temperature has a nearly steady viscosity, consequently demonstrate the best behavior during injection molding.