Experimental and theoretical methods for optimal solids loading calculation in MIM feedstocks fabricated from powders with different particle characteristics

Abstract

The aim of this work is to investigate the influence of the particle characteristics of powder to the mixing stage of the powder injection moulding process to identify the best procedure with which to evaluate the optimal solids loading for feedstock fabrication. To perform the present study, powder blends that are made from three bronze and four Inconel 718 powders, with different particle size distributions and morphologies, are mixed with a binder system that is based on polyethylene and wax. Powder–binder blends are prepared by varying the powder content to study how the powder characteristics affect the optimal solids loading. In addition, a new method is presented for determining the optimal solids loading in powder injection moulding feedstocks through the activation energy calculation of powder–binder blends that are prepared with different powder contents. This novel method is compared with the optimal loading values that have been determined by other ways as torque rheometry, determination of the tap-real density ratio and through rheological models.