The binders used in this work were of two types: binder I, comprising high-density polyethylene, paraffin wax and stearic acid as well as binder II, composing high-density polyethylene, polypropylene, polyethylene glycol 20000, paraffin wax and stearic acid. Therefore, based on these two types of binders, four combinations of feedstocks were categorized as follows: Ti-6Al4V+binder I (A), Ti-6Al-4V+binder II (B), Ti-6Al7Nb+binder I (C) and Ti-6Al-7Nb+binder II (D). The rheological behaviors of feedstocks were investigated at temperatures of 130, 140, 150, 160 and 170°C with different powder loadings varying from 57 to 71% volumetric. At low temperatures (130 °C), all feedstocks were observed to have a dilatant flow, while based on the results obtained from experiments, the suitable injection temperatures for these feedstocks were determined to be 140, 150 and 160°C. The critical powder loadings were found to be 65, 67, 67 and 71 vol.%, for feedstocks A,B,C and D, respectively.
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