Search Results for Engine components

This article focuses on friction, lubrication, and wear of internal combustion engine parts, improvements in which provide important gains in energy efficiency, performance, and longevity of the internal combustion (IC) engine systems. It discusses the types, component materials, and Friction and Wear Control of IC engine. The article explains the process of friction reduction by surface textures or coatings. It provides information on surface hardening of iron and steel, which is commonly employed for engine and powertrain components such as crankshafts, cams, and cylinder liners. The article also discusses advanced surface engineering technologies, such as diamondlike carbon coatings and surface texture technology. Information on thermal-spray methods that have led to improvements in engine components is also provided. The article describes IC engine-components wear, namely, piston assembly wear, valvetrain wear, cylinder-bore wear, and engine bearing wear. It concludes with information on inlet valve and seat wear of IC engine.

Fatigue failure of engineering components and structures results from progressive fracture caused by cyclic or fluctuating loads. Fatigue is an important potential cause of mechanical failure, because most engineering components or structures are or can be subjected to cyclic loads during their lifetime. This article focuses on fractography of fatigue. It provides an abbreviated summary of fatigue processes and mechanisms: fatigue crack initiation, fatigue crack propagation, and final fracture,. Characteristic fatigue fracture features that can be discerned visually or under low magnification are then described. Typical microscopic features observed on structural metals are presented subsequently, followed by a brief discussion on fatigue in polymers and polymer-matrix composites.

This article addresses the impact of emerging technologies on future lubricant and tribology requirements. The connection between lubricant and tribological requirements is shown by briefly describing basic lubrication and friction processes in major engine components incorporating emerging technologies. The article introduces automotive lubricant development activities and the foundation of future automotive engine-lubricant trends. It discusses how emerging powertrain technology impacts future automotive lubricant and technology requirements, focusing on the effects of engine oils and additives on engine performance to meet powertrain performance requirements. A detailed overview of automotive engine oil performance evaluation methods and specifications, and their impact on the types of advanced lubricants being developed as well as future automotive engine testing requirements, is provided.

Surface treatments are used in a variety of ways to improve the material properties of a component. This article provides information on surface treatments that improve service performance so that the design engineer may consider surface-engineered components as an alternative to more costly materials. It describes solidification surface treatments such as hot dip coatings, weld overlays, and thermal spray coatings. The article discusses deposition surface treatments such as electrochemical plating, chemical vapor deposition, and physical vapor deposition processes. It explains surface hardening and diffusion coatings such as carburizing, nitriding, and carbonitriding. The article also tabulates typical characteristics of carburizing, nitriding, and carbonitriding diffusion treatments.

This article, to develop an understanding of the underlying mechanisms governing deformation at elevated temperatures, discusses the phenomenological effects resulting from temperature-induced thermodynamic and kinetic changes. It describes the deformation behavior of engineering materials using expressions known as constitutive equations that relate the dependence of stress, temperature, and microstructure on deformation. The article reviews the characteristics of creep deformation and mechanisms of creep, such as power-law creep, low temperature creep, power-law breakdown, diffusional creep, twinning during creep deformation, and deformation mechanism maps. It discusses the creep-strengthening mechanisms for most structural engineering components. The article provides a description of the microstructural modeling of creep in engineering alloys.