M OLDABILITY OF MIM F EEDSTOCKS WITH VARYING
P ARTICLE S IZE D ISTRIBUTION AND S HAPE
PRAMOD REDDY TILLETI
MASTER THESIS REPORT
J
ULY2012
ABSTRACT
Metal Injection Molding (MIM) is one of the finest techniques available to manufacture intricate parts that cannot be produced by other techniques. MIM is a near net shape technique suitable for the production of moderate to large volumes of small complex metal. It combines the plastics injection molding technique with the powder sintering techniques to produce high density parts at close tolerances. MIM allows creating metal parts with a more complex shape and a uniform density compared with regular powder metallurgical sintered parts.
The scope of this thesis is testing for the moldability of MIM feedstocks with varying particle shape and particle size distribution. Metal powders with different particle sizes were chosen and feedstock was prepared with polymeric binder and tested for feedstock properties. By maintaining a uniform pressure, parts were injection molded, debinded &
sintered and metallographic examination was done to investigate the particle distribution in pre-sintered parts.
From the results, it can be concluded that the powder particle shape and particle size distribution dominantly influences not only the molding parameters, but also the final strength of the sintered components.
Keywords: particle size, injection molding, particle size distribution, feedstock.
Due to confidentiality reasons the rest of this report have been removed. Contact Ms. Anna Larsson Anna.Larsson@hoganas.com, Anna Larsson, Höganäs AB, 263 83 Höganäs, Sweden, for further details.
