The development of powder injection moulding binders: A quantification of individual components' interactions

Abstract

The study of interactions between binder system components is critical for improving the processing properties of powder injection moulding (PIM) feedstocks. In this paper the interactions between acrawax (AW) and polyethylene glycol (PEG) were analysed and compared with those obtained for carnauba wax (CW). Due to the complexity of interaction mechanisms, the polymers were substituted with their basic low molecular weight analogues and analysed by FTIR and calorimetry. Self-interaction energies and association energies were determined using calorimetric analysis. Shifts of FTIR absorption peaks (C-O stretch and N-H stretch) served as evidence of the presence of interactions between the components. The calorimetric study of AW/PEG analogues showed a temperature increase during mixing, indicating the presence of strong interactions. The combined data from FTIR and calorimetry allowed a quantitative evaluation, which indicated about two times stronger interactions between AW (with C=O and N-H groups) and PEG (with C-O and -OH groups), as compared to CW (with C=O and C-O groups) and PEG analogues.

Surface adhesion between ceramic injection molding feedstocks and processing tools

“…Melting point of the wax is of 82-86 1C. The last mentioned acrawax (N, N 0 -Ethylene Bis-stearamide) belongs to group of amidic waxes with melting point of 145 1C, and in the present study it has been considered as a possible alternative of carnauba wax because of its stronger interactions to other binder components evaluated in the recent work [18]. All components belonging to this group are more or less derivatives of fatty acids.…”

An investigation of moldability and mechanical properties of MgO added alumina

“…Powder injection molding (PIM) is an impressive method for the mass production of complex and dimensionally accurate parts with metal and ceramic powders [1]. The process is the hybrid of powder technology and conventional plastic injection molding [2].…”

“…The debinding is the most difficult stage due to the formation of defects, for example, swelling and cracking in the part body. To overcome or reduce these problems, different debinding techniques have been improved [1,[11][12][13][14][15]. In the final stage, the porous part is sintered to compact the desired properties [16].…”

Rheological and thermal performance of newly developed binder systems for ceramic injection molding

“…Recently, substantial effort has been put to investigate the role of particular binder components and their interactions with ceramic powders as well as mold channel walls as a base for development of a novel, environmentally friendly CIM feedstocks [3][4][5].…”

“…Specific interactions of the substitutes were evaluated using combined FTIR and analogue calorimetry. Highest cross interaction values suggesting strong interactions were obtained for analogues of PEG and acrawax [4]. The adhesion between binder system components, as well as binders, powders and the mold materials was investigated via contact angle analysis, and using acid base model, surface energies were evaluated [5].…”