Development of PEG/PMMA Based Binders for Ti-Metal Injection Moulding

Abstract:

As the world is moving towards green manufacturing, there is an increasing demand for the use of clean and environmentally friendly binder systems in metal injection moulding (MIM) industry. One example of these developed binders is polyethylene glycol (PEG) - polymethyl methacrylate (PMMA) based system. We have systematically evaluated and optimized this binder system, and reported some interesting new results. In this article, we reported the effect of PEG molecular weight on rheological properties of the feedstock and its water debinding behaviour. We also investigated the effects of different surfactants on MIM feedstock rheological and mechanical properties, and identified a potential surfactant that enhances compatibility between the binder components and metal powders. Furthermore, we reported an interesting problem – ‘voids formation’, which is associated with PEG crystallization. To minimize this void formation a crystallization inhibitor is incorporated in the PEG/PMMA system, thereby eliminating the void formation while maintaining the clean nature of this system. This paper is concluded with some new thoughts with regard to binder design.

• Periodical: Key Engineering Materials (Volume 704)
• Pages: 130-138
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.704.130
• Online since: August 2016
• Authors: Muhammad Dilawer Hayat, Peng Cao*
• Keywords: Metal Injection Moulding, PEG/PMMA Binder System, Surfactant, Titanium, Void

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