The reciprocating wear behaviour of TiC-304L stainless steel composites prepared by melt infiltration

TiC-based ceramic-metal composites, or cermets, are widely used in applications requiring wear and corrosion resistance. In the present work, a family of novel TiC-stainless steel (grade 304L) cermets has been developed using vacuum melt infiltration (1500 degrees C/1 h), with steel binder contents varied from 5 to 30 vol%. Microstructural analysis showed a homogenous distribution of TiC within the steel binder, with mean TiC grain sizes of similar to 6 mu m. Increasing the steel content resulted in an increase in the indentation fracture resistance and a decrease in the hardness. The reciprocating wear resistance of the cermets was assessed using a ball-on-flat geometry, using a WC-Co sphere dry sliding on the polished cermet surface. It was shown that there is an increase in the specific wear rate with both increasing load and binder content. Similarly, a higher coefficient of friction was observed with higher steel binder contents. The morphology of the worn surface was investigated using scanning electron microscopy, and associated energy dispersive X-ray spectroscopy, to more fully understand the operative wear mechanisms. Evidence of a transition from two- to three-body abrasive wear was observed, together with the formation of a tribolayer, indicating that adhesive wear was also occurring. (C) 2013 Elsevier B.V. All rights reserved.