C. Binder, R. Binder, D.R. Consoni, G. Hammes, R. Schroeder, A.N. Klein, J.D.B. de Mello
Universidade Federal de Santa Catarina, Brazil
pp. 616 - 619
Keywords: composites, in situ, turbostratic graphite, self lubricating
In this paper we present a new processing route able to produce a homogeneous dispersion of in situ generated, discrete solid lubricant particles in the volume of sintered steels produced by metal injection molding. Preliminary results indicated that they are very well suited to applications in the refrigeration industry, in particular the Wisemotion® family, the world’s first oil-free compressor for home appliances. Thermal debinding and sintering were performed in a single thermal cycle using a Plasma Assisted Debinding and Sintering (PADS) process. Nodules of graphite (size ≤ 20μm) presenting a nanostructured stacking of graphite foils with thickness of a few nanometers were obtained. Micro Raman spectroscopy indicated that the graphite nodules are composed of a so-called turbostratic 2D graphite which has highly misaligned graphene planes separated by large spaces. The effects of precursor content, metallic matrix composition and sintering temperature are presented and discussed. The results clearly show the great tailoring ability of the proposed micro-structural model when applied to the development of self lubricating composites. Moreover, the optimized processing parameters produced outstanding new iron based composites.