The tribo-performance behaviors of lubricated textured point contacts have been explored herein at relatively high contact loads (up to 3 GPa) under reciprocating motion (0.2 and 0.4 m/s) employing low (ν@40 ℃ = 100 cSt) and high (ν@40 ℃ = 422 cSt) viscous oils. In this experimental study, two contacts (flat conventional surface vs. polished ball and textured flat surface vs. polished ball surface) have been created for the investigations of friction, wear, and contact potential (ability for film formation). It is found that in the presence of texture at the concentrated contacts, the coefficient of friction and wear have reduced considerably with high viscous oil irrespective of operating parameters. However, low viscous oil has yielded an increase in the wear under identical operating parameters. The contact potential (an indirect indication of film formation during the running-in period) in the presence of texture develops rapidly as compared to the conventional surface with both oils. It has demonstrated a reduction in the running-in period in the presence of textures at the contacts. The optical microscope images of worn surfaces of balls and tracks have also been presented for the quantification of wear and understanding of the associated mechanisms.

Tribo-behaviours of grease-lubricated textured point contacts were experimentally explored at heavy loads (characterized in term of Hertzian pressure, P H  = 1.5–3.0 GPa) and relatively low sliding speeds (0.2 and 0.4 m s−1) under the linear reciprocating motion employing lithium-based low and high consistency greases. Two contacts (grounded plate versus lapped ball & grounded textured plate versus lapped ball) were employed for the comparative investigations of friction coefficient, specific wear rate, and contact potential. Effects of grease consistency on the greases’ rheological behaviours have also been found at two temperatures 25 °C and 80 °C using controlled stress rheometer. Overall, textured concentrated contacts yielded a low coefficient of friction (reduction up to 24.6%), reduced specific wear rate of the ball (decrease up to 89.5%) and better development of contact potential in comparison to conventional contacts. The transmission electron microscopy (TEM) of used greases collected from textured contacts revealed less degradation in soap fibres. Moreover, the x-ray photoelectron spectroscopy (XPS) revealed the formation of ferric oxide (Fe2O3) and ferrous-ferric oxide (Fe3O4) protective chemical films on the worn surfaces of balls of the conventional and textured contacts.