US EPA

5322262 

Journal Article 

Effects of milling and active surfactants on rheological behavior of powder injection molding feedstock 

Fan, JL; Huang, BY; Qu, XH 

2001 

1 

Transactions of Nonferrous Metals Society of China
ISSN: 1003-6326 

11 

2 

196-199 

WOS:000167946900008 

The effects of milling and active surfactants on the theological behavior of powder injection molding feedstock were discussed. The feedstock consists of traditional compositional 90W-7Ni-3Fe powder mixture and a wax based polymer binder. Before mixing feedstock, the powder mixture was milled for different times in a QM-1 high-energy ball mill. The viscosity of the feedstock was examined in a capillary rheometer. The theological behavior was evaluated from viscosity data. The results show that the feedstock belongs to a pseudoplastic fluid, milling decreases viscosity of the feedstock and the sensitivity of viscosity to shear strain rate. The flowability, theology and powder loading of this feedstock are improved by milling. Active surfactants such as stearic acid (SA) and di-n-octyl-o-phthalate (DOP) have great influences on the theological properties of the feedstock. DOP improves the flowability and theological stability of the feedstock further. 

milling; active surfactant; theological behavior