Powder injection moulding of cemented carbides: Feedstock preparation and injection moulding

Authors

  • Nutthita Chuankrerkkul Metallurgy and Materials Science Research Institute, Chulalongkorn University
  • Peter F. Messer Department of Engineering Materials, University of Sheffield
  • Hywel A. Davies Department of Engineering Materials, University of Sheffield

Keywords:

powder injection moulding, cemented carbides, tungsten carbide-cobalt, PEG/PMMA composite binder

Abstract

A composite binder system, successfully developed earlier for powder injection moulding of stainless steels, CoCrMo and NiCrSiB alloys, has been adapted for tungsten carbide-cobalt (WC-Co) cemented carbides. The binder consists of a major fraction of polyethylene glycol (PEG), which can be removed rapidly by leaching with water, a minor fraction of a finely dispersed polymethyl methacrylate (PMMA), which retains rigidity of the components and sometimes with stearic acid (SA) to act as a lubricant. The adjustments made to powder characteristics, binder compositions and process parameters to achieve successful injection moulding are reported. Feedstocks containing a powder loading of the WC-Co up to 60 vol% can be moulded successfully. The moulded specimens had good green strength, in the range 12-17 MPa for three point bend tests.

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References

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Published

2017-04-23

How to Cite

[1]
N. Chuankrerkkul, P. F. . Messer, and H. A. . Davies, “Powder injection moulding of cemented carbides: Feedstock preparation and injection moulding”, J Met Mater Miner, vol. 17, no. 1, Apr. 2017.

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Original Research Articles

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