Water soluble Invar 36 feedstock development for μPIM

A water soluble binder system based on cellulose acetate butyrate (CAB) and polyethylene glycol (PEG) is proposed and investigated to carry out a micro powder injection moulding (μPIM) process with an Invar 36 alloy powders. The overall process was optimised with an emphasis on the determination of the optimal solid loading. Several methodologies were evaluated and compared to determine this parameter. A full μPIM was performed with different powder content feedstocks. Dog bone-type micro test parts were fabricated thereof and their mechanical properties were evaluated. Solid loadings up to 65 vol.% resulted to have the most equilibrated properties to successfully fabricate Invar 36 micro parts with the selected powder and binder system.