Rheological properties of mixed gas and water atomized stainless steel powder MIM feedstock

Karatas C., Saritas S.

INTERNATIONAL JOURNAL OF POWDER METALLURGY, vol.37, no.8, pp.39-44, 2001 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 37 Issue: 8
  • Publication Date: 2001
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.39-44
  • Gazi University Affiliated: No


Feedstocks were compounded using 316L stainless steel powders produced by gas atomization, water atomization and by taking ratios of the two powders. A conventional polypropylene-based binder was employed in all of the feedstocks. Mixing of the powders and the binder components was done first in a blender in the solid state and then in a twin-screw extruder where the binder was in the liquid state. Median sizes (d(50)) of the 316L stainless steel powders were: 10.27 mum, 13.78 mum, 1724 mum, 19.94 mum, 25.06 mum and 30.4 mum. For each 316L powder sample, feedstocks with different solid loadings were prepared and their rheological properties measured utilizing a capillary rheometer. Mixing of the gas-atomized and water-atomized 316L powders improved significantly their rheological properties. In particular, higher solids loadings and lower viscosities were obtained. These characteristics of the mixed powders offer potential as a commercial feedstock in powder injection molding.