Nanoparticles (NPs) additives have gained notable influence in technology advancements owing to their excellent physiochemical properties with enhanced performance in application compared to previously used additives. The field of tribology has contributed significantly towards upgrading the overall engine efficiency through use of lubricating materials. The outstanding technique in achieving this is through adoption of additives derived from nanotechnology capable of preventing friction and wears during engine operations. Since only base oil cannot withstand most of the operating conditions, suitable additives are formulated and blended as to enhance the tribological properties. According to some research, nanoparticle additions have a greater impact on lubricant improvement. The ability to design NPs additives with unique qualities raises the value and demand for such class of products. The purpose of this study is to highlight the promising properties of NPs additives, mechanisms and to define the specific knowledge gaps related to the size of NPs towards friction and wear reduction. The function and mechanism performance of NPs additives during operation, such as mending, rolling, film formation, and polishing effect, is determined by their types. The excellent load carrying capability of nanoparticles during lubrication reflects their outstanding performance. The review presents an overview of the history and classifications of NPs and concisely elucidate their tribological effect when applied in lubrication. Excellent function of nano additives is the attribute of its nanoscale (1 to 100 nm) nature, thus categorized base on their size, shape, origin and composition. Certain expected characteristics of lubricating oil like friction and wear resistance, surfactant operation, load carrying capacity, extreme pressure operation, etc. were achieved through inclusion of nanoparticles additives.
Keywords: Nano particle additives, classifications, lubrications, mechanisms, friction and wear effect.