Systematic planning of an activity is a key factor for the success of any event. It is well said that ‘If Well planned, 90% of the work is completed’. But planning a successful activity depends on how sustainable the solutions would be. For machinery too, the maintenance planning is to be sustainable, particularly the lubrication. Additionally, with the concern of the environment now industries are looking for sustainable but environment-friendly economical solutions. Lubricants which form one of the major mechanical elements need to be taken into high consideration. However, it is important to understand the role of these lubricants in mechanical applications and choose the correct lubricant for specific applications.
The special issue focuses on various tribological systems from nano to macro scale. This issue brings together interesting contributions both from industry and academia covering applications such as wind turbines, nano-bio-lubricants, self-lubricating nanocomposites, coatings, and natural composite brake pads. The topics covered diverse topics highlighting innovative scientific approaches covering modern lubrication techniques. The special issue is divided into two sections: initial articles focus on the lubrication aspects of industrial applications and later articles focus on the composites and coatings, thus, covering several dimensions in the field of tribology.
The issue begins with an interesting manuscript ‘Investigating the effect of temperature and time on the starvation of lubricants for the wind turbine industry’ where Georgiou et al. developed a validation test procedure and reported the effect of temperature and time on lubrication starvation in windmills.
Sustainable lubricants are the need of the hour. Biodegradable lubricants are lubricants of interest to the environmental policies of all nations. In ‘Performance Assessment of Some Selected Vegetable Oils as Lubricants in Turning of AISI 1045 Steel Using a Taguchi-Based Grey Relational Analysis Approach’, Abegunde et al. reported the efficacy of vegetable oil in turning AISI 1045. The incorporation of nanotechnology in lubricants had exhibited an improvement in the tribological properties of lubricants. Srivyas et al. evaluated the tribological properties of a hybrid nanoparticle added poly alpha olefin oils in ‘Enhanced Extreme Pressure and Tribological Performance of Hybrid Nano Lubricant’ and reported a significant reduction in frictional coefficient. Furthermore, in ‘Tribological Evaluation of Rice Bran Oil Based Ionanolubricants Containing Ionic Liquids and Nanoparticles’. Garg et al. reported an improvement in the tribological properties of rice bran oil by introducing ionic liquids along with nanoparticles.
Recent advances in self-lubricating composites have also been an area of interest in this issue. In several applications, composites need to be wear-resistant and one of the most exciting topics is self-lubricating composites. ‘Investigations on the temperature-dependent tribological behavior of spark plasma sintered CNT- 304 SS self-lubricating nanocomposites’ by Radhamani et al., report the results on the enhanced tribological properties of CNT-incorporated 304 stainless steel at high temperatures, particularly for applications of oil and gas industry. The results are quite interesting as they reported a significant reduction in wear at high temperatures. Additionally, the process of incorporating CNTs in steel by sintering is also noteworthy. Natural composites are also being used in brake pads. The manuscript ‘Recent Progress in the Research on Natural Composite Brake Pads: A Comprehensive Review’ by Bharath KN et al. thoroughly reviewed the recent progress in natural composites. The manuscript further discussed the wear mechanisms involved in various materials of brake pads and concluded with the possibility of manufacturing such natural composite brake pads using modern techniques. An excellent anti-wear property of WS2 solid lubricant coating on the aluminium substrate was reported in ‘Wear characteristics and sustainability of WS2 solid lubricant deposited layer on Al 6061-T6 substrate under the dry sliding conditions’ by Rajeshshyam R. The manuscript reported the wear reduction property of WS2 coatings and hence, is suitable for several industrial applications. Hence, it can be seen that the special issue has focused not only on regular academic research but also on industrial applications.
This Special Issue came to light after a series of positive discussions with the Journal’s Editorial Board, particularly with Prof. Tomasz Liskiewicz. I express my sincere gratitude to the journal’s editorial office, which ensured hassle-free publications of these interesting manuscripts following a rigorous independent peer review process. Also, I would like to thank the reviewers who reviewed all the manuscripts and gave their valuable comments for the manuscripts.