The reciprocating wear behaviour of TiC–Ni3Al cermets

TiC-based cermets have become more popular as a replacement to traditional WC–Co ‘hardmetals’ due to their superior mechanical properties at elevated temperatures, improved corrosion resistance and significantly lower density. The current study assesses the reciprocating wear response of TiC–Ni3Al cermets fabricated by melt infiltration, with Ni3Al binder contents ranging from 20 to 40vol.%. Wear testing was performed using a ball-on-flat geometry, with a WC–Co sphere used as the counter-face material. It is demonstrated that the cermets are affected by similar wear mechanisms for each of the binder contents, but displayed the lowest wear when prepared with 30vol.% Ni3Al. Additionally, the 40vol.% samples displayed a clear transitional behaviour, with an improved wear resistance comparable to the 30vol.% samples at low applied loads, but a degraded wear response comparable to the 20vol.% samples at high applied loads. ► The reciprocating wear behaviour of TiC–Ni3Al cermets has been assessed. ► A range of Ni3Al binder contents (20 to 40 vol.%) and applied loads was investigated. ► Wear was characterised using optical profilometry in combination with scanning electron microscopy. ► Intermediate Ni3Al contents (30 vol.%) exhibited the best wear resistance, while the lowest (20 vol.%) exhibited the worst. ► The wear mechanism is a combination of abrasive 2-/3-body wear, with evidence of adhesive wear (i.e. tribolayer formation).