Friction and wear in mechanical systems contribute significantly to energy consumption, economic losses, and greenhouse gas emissions, necessitating urgent solutions to these tribological challenges. This dissertation addresses these issues by exploring the potential of carbon microspheres (CMS) as lubricant additives and fillers in polymers to mitigate friction and wear between surfaces in motion. The introductory chapter provides foundational knowledge on lubrication mechanisms and lubricant additives. Following this, the synthesis, characterization, and application of carbon microspheres are discussed in the second chapter. Chapter three delves into a fundamental study exploring the contribution of particles to lubrication across varying speed and load conditions in dilute particle-lubricant systems, utilizing CMS-dispersed lubricants. The concept of the Stribeck curve is employed to analyze the effects, revealing that particles are effective in the boundary lubrication regime but lose effectiveness as the system transitions to the hydrodynamic lubrication regime. A mathematical relation is proposed to calculate the specific film thickness, aiding in determining the lubrication regime accurately. In chapter four, the application of carbon spheres (CS) as fillers in low-density polyethylene (LDPE) to enhance mechanical and tribological properties is discussed. The fabrication process of LDPE/CS composites is outlined, alongside structural, thermal, mechanical, and tribological characterization. Emphasis is placed on assessing the impact of critical parameters such as load, speed, and surface roughness on friction and wear characteristics. The final chapter presents ongoing work on a blended water-based lubricant aimed at significantly reducing friction and improving wear resistance through a dual lubrication mechanism. A novel lubricant comprising deionized water, MXene nanosheets, and carbon spheres is developed and tested for friction reduction properties. Suggestions are offered to improve this lubricant blend, offering a roadmap to potentially attaining an ecofriendly water-based lubricant with superlubricity potential.
