Effect of a binder system on the low-pressure powder injection moulding of water-soluble zircon feedstocks

Micronized natural zircon sand powders were used as a raw material to conduct low-pressure powder injection moulding (LPPIM) processes. PIM could lead to new technological applications for this mineral, which has very stable dimensional behaviour with changing temperature. Zircon powders that have unconventional attributes for PIM (in terms of size and morphology) were mixed with poly(ethylene glycol) (PEG) based binders. Combinations of this water-soluble substance with different polymers, including low-density polyethylene (LDPE) and several types of acetate butyrate celluloses (CAB), were investigated. The influence of acetyl, butyryl and hydroxyl groups on the behaviour of the created feedstocks at different process stages and on the final piece properties were studied. The higher affinity of CAB with PEG and zircon powders compared with LDPE could result in improved densification and properties, but the butyryl, acetyl and hydroxyls groups affect the processability of these feedstocks.