Superamphiphobic (water and oil repellent) surfaces have distinct application areas such as anti-corrosion, anti-friction, anti-icing, self-cleaning, etc. To fabricate these types of surfaces, the base material must have low surface energy and dual-scale roughness (micro and nano levels). The durability of such surfaces is indicated by the duration up to which they remain stable and effective. When mechanical forces interact with these surfaces, it deteriorates the surface integrity and ultimately degrades its superamphiphobic property. Hence, these surfaces have very limited mechanical wear sturdiness and long-term durability. Therefore, in this article, efforts have been made to review the different types of mechanical durability tests performed on superamphiphobic metallic and non-metallic surfaces. Moreover, various kinds of surface texturing techniques in context with durability of such surfaces have been discussed. Finally, from the reported literature, critical conclusions, challenges, and scopes for future work have also been presented.

The aim of this research is to create self-cleaning hydrophobic and superhydrophobic surfaces (SHS) on a glass substrate. Carbon soot has been deposited from the candle flame in order to manufacture a SHS on glass slides. The water contact angle (WCA) and roll-off angle were measured after carbon soot deposition using a test rig built in the laboratory. Further, to make SHS on glass slides more robust, candle wax and vassilline were applied on a glass substrate with or without roughening it using emery paper of grade (P80, P220 & P400). The highest WCA was 160° for a candle sooted on glass roughened with emery paper of grade P80 using vassilline as an adhesive. The mechanical durability of the prepared surfaces has been investigated using a peel-off technique with highly glue adhesive tape. The WCA was measured after each peel-off to check the changes in the degree of wettability of the fabricated surface. From the investigation, it has also been observed that more roughened glass slides show more resistance to the removal of carbon soot.

The present study evaluates the combined use of micro‐textures and ‘wettability gradient’ on the thermohydrodynamic performance of inclined slider bearings. Mass conserving Elrod cavitation model with slip boundary condition has been used to investigate the dimensionless static performance parameters at different convergence ratios and sliding speeds. The most effective location of the wettability gradient and textures has been considered in the present work. It has been observed that with the increase in sliding speed, the load carrying capacity, friction force and volumetric inflow rate of the slip‐textured bearings were improved. The improvements were more pronounced at smaller convergence ratios. Moreover, the slip‐textured bearings exhibited significant improvement in the average pressure and temperature of the lubricant. However, at higher sliding speeds, a substantial increase in friction force and average lubricant temperature was noticed. The square textured slip bearing exhibited maximum improvements towards various performance parameters of the three considered texture shapes.

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