Waste plastic proposed as a binder for Metal Injection Moulding

July 12, 2019

A team of researchers has found a way to use waste plastic as a binder for Metal Injection Moulding, successfully employing the technique to produce stainless steel medical components (Courtesy SIRIM Berhad)

A team of researchers at SIRIM Berhad, Shah Alam, Malaysia, led by Dr Mohd Afian Omar, has found a way to make use of waste plastic as a binder in the Metal Injection Moulding process. The technique is described as an eco-friendly way to recycle waste materials, and has been successfully employed to produce high-grade stainless steel medical implant components.

“We call it the Eco-Friendly Binder System,” explained Dr Afian. “Our recipe uses waste materials such as waste plastic as a cheap and easily-sourced material for the binder in the moulding process.” For the research project, waste thermoplastic powder was obtained from waste polyolefin, such as that used in water bottles, shampoo bottles and milk bottles, by mechanical grinding. The powder was then sieved to achieve an average particle size of 200 µm.

“Because the binder is discarded during the moulding process, it is preferable for it to be made of something cheap and plentiful,” stated Dr Afian. “It is not a part of the metal itself, so why should it add to the cost of the product?”

Every company has its own binder formula, most of which are petroleum-based formulas such as polyethylene and polypropylene, which are not typically eco-friendly. By using waste plastic mixed with wax, Dr Afian stated that he has found a binder material that has zero ecological impact. “With our process, any recycled plastic will do: mineral water bottles, shampoo bottles, even toys,” he commented.

The project is a collaborative effort between researchers at SIRIM and additional researchers at the University Sains Malaysia (USM) and International Islamic University of  Malaysia (IIUM). The eco-friendly binder has been shown to work with many other alloys in addition to stainless steel, and SIRIM is now continuing its research to improve the process while evaluating the suitability of the binder system with other types of metals such as high-speed steel, cobalt-based alloys and titanium.

The waste plastic binder composition is not only environmentally friendly and non-hazardous, but also enables moulding of feedstock at low moulding temperatures and pressures. This results in less wear on tooling and allows for the use of less expensive tooling materials, such as aluminium, for relatively low-volume production of green parts.

Contact: Dr Mohd Afian Omar, [email protected]

Spring 2023 issue of PIM International magazine

In the latest issue of PIM International…

Download PDF

Extensive MIM, CIM industry and sinter-based AM industry news, plus the following exclusive deep-dive articles and reports:

  • Visottica Group: Integrated workflows and the value of Metal Injection Moulding in eyewear and beyond
  • In MIM’s post-smartphone era, where is China’s Metal Injection Moulding industry going?
  • Ceramic AM at scale: The story of how Steinbach AG scaled production to 12,000 parts a year for Da Vinci Surgical Systems
  • MIM F75 (Co-Cr-Mo) for high-volume production: The impact of sintering conditions on microstructure and properties
  • World PM2022: Research into the Binder Jetting of aluminium, Ni-free stainless steel, hardmetals and metallic glass

The latest news from the MIM, CIM and sinter-based AM industries

Don't miss any new issue of PIM International, and stay up to date with the latest industry news. Sign up to our fortnightly newsletter.

Sign up

Join our community

News from the industry…

    Discover our magazine archive…

    The free-to-access PIM International magazine archive offers unparalleled insight into the world of MIM, CIM and sinter-based AM from a commercial and technological perspective through:

    • Reports on visits to leading part manufacturers and industry suppliers
    • Articles on technology and application trends
    • Information on materials developments
    • Reviews of key technical presentations from the international conference circuit
    • International industry news

    All past issues are available to download as free PDFs or view in your browser.


    Browse the archive


    Looking for suppliers of materials, production equipment and finished MIM, CIM or sinter-based AM parts?

    Discover suppliers of these and more in our advertisers’ index and buyer’s guide, available in the back of PIM International.

    • Metal powders
    • MIM, CIM & AM parts producers
    • Binders & feedstocks
    • Feedstock mixers
    • Furnaces & furnace supplies
    • Atmospheres & gas generation
    • HIP systems & services
    • Injection moulding machines
    • AM technology
    • Debinding systems
    Download PDF
    Share via
    Copy link
    Powered by Social Snap