Engine Tribology

Abstract

In conventional internal combustion (IC) engines, significant part of fuel energy is dissipated in terms of heat and friction which results in lower energy efficiency. In addition, the exhaust emissions and release of particulate matter by engines is a source of rise in greenhouse effect. Keeping in view of current global environmental awareness, a new technical mandate for modern IC engines has been established in terms of efficiency and engines exhaust emissions. Modern tribology has helped in achieving this mandate with the advancement of research in smart surface engineering and coating technologies. Recent research contributions in DLC coating technology offer unique opportunities to enhance energy efficiency by reducing friction and wear of various parts of the engine. The key features of DLC coatings include low thickness, high durability, better mechanical and superior tribological properties as well as resistance to chemical and corrosive attacks. This chapter presents the details of various parasitic losses in IC engines, major engine subsystems with relevant tribo-pairs, modern engine tribology and role of coating technologies, DLC coating for engine parts, lubrication regimes and synergy between DLC coatings and lubricating additives, impact of DLC coatings on engine energy efficiency and environment, challenges and future outlook.