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Review Article | Open Access

Tribological behaviour of sintered iron based self-lubricating composites

Jose Daniel Biasoli DE MELLO1,2( ), Cristiano BINDER1, Gisele HAMMES1, Roberto BINDER3, Aloisio Nelmo KLEIN1
 Laboratorio de Materiais (LabMat), Universidade Federal de Santa Catarina, Florianópolis 88.040-900, SC, Brazil
 Laboratorio de Tribologia e Materiais, Universidade Federal de Uberlândia, Uberlândia 38.400-902, MG, Brazil
 Whirlpool, Embraco Unit, Joinville 89.219-900, SC, Brazil
Show Author Information

Abstract

This work is a review of previous works, presenting and discussing the most important results obtained by an ongoing research program towards the development of innovative, low-cost, self-lubricating composites with a low friction coefficient and high mechanical strength and wear resistance. Special emphasis is given to uniaxial die pressing of solid lubricant particles mixed with matrix powders and to metal injection moulding associated with in situ generation of solid lubricant particles. Initially, a microstructural model/ processing route (powder injection moulding followed by plasma-assisted debinding and sintering) produced a homogeneous dispersion of in situ generated solid lubricant particles. Micrometric nodules of graphite with diameter smaller than 20 μm were formed, constituting a nanostructured stacking of graphite foils with nanometric thickness. Micro Raman analysis indicated that the graphite nodules were composed of turbostratic 2D graphite having highly misaligned graphene planes separated by large interlamellae distance. Large interplanar distance between the graphene foils and misalignment of these foils were confirmed by transmission electron microscopy and were, probably, the origin of the outstandingly low dry friction coefficient (0.04). The effect of sintering temperature, precursor content, metallic matrix composition and surface finish is also reported. Furthermore, the influence of a double-pressing/double-sintering (DPDS) technique on the tribological performance of self-lubricating uniaxially die-pressed hBN + graphite-Fe-Si-C-Mo composite is also investigated. Moreover, the tribological behaviour of die-pressed Fe-Si-C matrix composites containing 5, 7.5 and 10 wt% solid lubricants (hBN and graphite) added during the mixing step is analysed in terms of mechanical properties and wear mechanisms. Finally, the synergy between solid lubricant particles dispersed in a metallic matrix and fluid lubricants in a cooperative mixed lubrication regime is presented.

Keywords

tribological behaviourpowder metallurgyiron basedself-lubricatingcompositesturbostratic graphite

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Friction
Volume 5 Issue 3,
September 2017
Pages 285-307
DOI: 10.1007/s40544-017-0186-2
Cite this article:
DE MELLO JDB, BINDER C, HAMMES G, et al. Tribological behaviour of sintered iron based self-lubricating composites. Friction, 2017, 5(3): 285-307. https://doi.org/10.1007/s40544-017-0186-2

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Received: 09 June 2017
Revised: 01 August 2017
Accepted: 22 August 2017
Published: 06 September 2017
© The author(s) 2017

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