This article is dedicated to the fields of mechanical engineering and machine design. It also intends to give a nonexhaustive view of the preventive side of the failure analysis of rolling-element bearings (REBs) and of some of the developments in terms of materials and surface engineering. The article presents the nomenclature, numbering systems, and worldwide market of REBs as well as provides description of REBs as high-tech machine components. It discusses heat treatments, performance, and properties of bearing materials. The processes involved in the examination of failed bearings are also explained. Finally, the article discusses in detail the characteristics and prevention of the various types of failures of REBs: wear, fretting, corrosion, plastic flow, rolling-contact fatigue, and damage. The article includes an Appendix, which lists REB-related abbreviations, association websites, and ISO standards.

Rolling-element bearings use rolling elements interposed between two raceways, and relative motion is permitted by the rotation of these elements. This article presents an overview of bearing materials, bearing-load ratings, and an examination of failed bearings. Rolling-element bearings are designed on the principle of rolling contact rather than sliding contact; frictional effects, although low, are not negligible, and lubrication is essential. The article lists the typical characteristics and causes of several types of failures. It describes failure by wear, failure by fretting, failure by corrosion, failure by plastic flow, failure by rolling-contact fatigue, and failure by damage. The article discusses the effects of fabrication practices, heat treatment and hardness of bearing components, and lubrication of rolling-element bearings with a few examples.

This article discusses the physical signs of rolling-contact wear (RCW). It lists the major considerations in gear design and describes the mechanisms of RCW. The article provides a guide to rolling-contact fatigue (RCF) testing methods. It explains the steps involved in the processes of RCF and RCW.

Rolling-contact fatigue (RCF) is a common failure mode in components subjected to rolling or rolling-sliding contact. This article provides a basic understanding of RCF and a broad overview of materials and manufacturing techniques commonly used in industry to improve component life. A brief discussion on coatings to improve surface-initiated fatigue and wear is included, due to the similarity to RCF and the increasing criticality of this failure mode. The article presents a working knowledge of Hertzian contact theory, describes the life prediction of rolling-element bearings, and provides information on physics and testing of rolling-contact fatigue. Processes commonly used to produce bearings for demanding applications are also covered.

Rolling-element bearings, also called rolling bearings and antifriction bearings, tend to have very low friction characteristics compared to plain bearings or simple sliding bearings. This article discusses the types of rolling-element bearings, namely, ball bearings and roller bearings. It provides information on the bearing component materials. The article describes the lubrication requirements and lubrication methods, namely, elastohydrodynamic lubrication and grease lubrication. It reviews the adjustment factors influencing fatigue life of the bearing. The article also provides information on bearing load ratings, standard bearing geometries, rolling bearing friction factors, and wear and its control methods. It concludes with a discussion on damage modes of bearings.

This article discusses the functions of lubricants to prevent premature failure of rolling element bearings and the advantages of fluid lubrication. It describes the composition of refined mineral oil for rolling bearing applications. The article reviews the types and properties of nonpetroleum oils, such as polyglycols, phosphate esters, silicone fluids, dibasic acid esters, and fluorinated polyethers. It discusses the properties of greases, including grease speed limits, grease composition, relubrication intervals, corrosion prevention behavior, and grease compatibility. The article concludes with a discussion on polymeric lubricants and solid lubricants.

The mechanism of contact fatigue can be understood in terms of several sources of stress concentration, or stress raisers, within the macroscopic Hertzian stress field. This article focuses primarily on rolling contact fatigue of hardened bearing steels. It discusses Hertzian shear stresses at and below the contact surfaces and briefly summarizes bearings and gear characteristics. The article provides an overview of the key types of gear and bearing steels. It analyzes two types of macropitting that result from the subsurface growth of fatigue cracks, namely, subsurface-origin macropitting and surface-origin macropitting. The article describes the factors influencing contact fatigue life of hardened steel bearings and gears, including hardness, inclusions, carbides, and residual stresses.

A major cause of failure in components subjected to rolling or rolling/sliding contacts is contact fatigue. This article focuses on the rolling contact fatigue (RCF) performance and failure modes of overlay coatings such as those deposited by physical vapor deposition, chemical vapor deposition, and thermal spraying (TS). It provides a background to RCF in bearing steels in order to develop an understanding of failure modes in overlay coatings. The article describes the underpinning failure mechanisms of TiN and diamond-like carbon coatings. It presents an insight into the design considerations of coating-substrate material properties, coating thickness, and coating processes to combat RCF failure in TS coatings.

Contact fatigue is a surface-pitting-type failure commonly found in ball or roller bearings. This article discusses the mechanisms of contact fatigue found in gears, cams, valves, rails, and gear couplings. It discusses the statistical analysis of rolling contact bearing-life tests. The article concludes with information on various approaches that improve the contact fatigue resistance of rolling contact systems.

Rolling-contact fatigue (RCF) is a surface damage process due to the repeated application of stresses when the surfaces of two bodies roll on each other. This article briefly describes the various surface cracks caused by manufacturing processing faults or blunt impact loads on ceramic balls surfaces. It discusses the propagation of fatigue cracks involved in rolling contacts. The characteristics of various types of RCF test machines are summarized. The article concludes with a discussion on the various failure modes of silicon nitride in rolling contact. These include the spalling fatigue failure, the delamination failure, and the rolling-contact wear.

This article provides an overview of two major classes of bearings: rolling bearings and sliding, or plain, bearings. It reviews the experimental data resulted from testing of rolling and sliding bearing materials with illustration. The article presents a table that summarizes rolling contact fatigue test methods that ASTM published in STP 771. It also describes the role of lubrication in the bearings.

This article provides information on the nominal compositions of high-carbon bearing steels and carburizing bearing steels. It discusses the bearing fundamentals with emphasis on surface contact, stresses, and fatigue life of bearings. The article describes bearing life prediction using three factors, namely, reliability, material, and application. It analyzes the bearing damage modes and concludes with information on fatigue failure considerations.

This article discusses the composition, properties and applications of bearing steels. It focuses on the typical wear modes that rolling-element bearings experience: contact fatigue wear, abrasive wear, adhesive wear, and corrosive wear. The article provides information on reliability factor and ABMA and ISO environmental factors.

Copper and copper alloys are used extensively in structural applications in which they are subject to moderately elevated temperatures. At relatively low operating temperatures, these alloys can undergo thermal softening or stress relaxation, which can lead to service failures. This article is a collection of curves and tables that present data on thermal softening and stress-relaxation in copper and copper alloys. Thermal softening occurs over extended periods at temperatures lower than those inducing recrystallization in commercial heat treatments. Stress relaxation occurs because of the transformation of elastic strain in the material to plastic, or permanent strain.

A mechanical part, which supports the moving part, is termed a mechanical bearing and can be classified into rolling (ball or roller) bearings and sliding bearings. This article discusses the failures of sliding bearings. It first describes the geometry of sliding bearings, next provides an overview of bearing materials, and then presents the various lubrication mechanisms: hydrostatic, hydrodynamic, boundary lubrication, elastohydrodynamic, and squeeze-film lubrication. The article describes the effect of debris and contaminant particles in bearings. The steps involved in failure analysis of sliding bearings are also covered. Finally, the article discusses wear-damage mechanisms from the standpoint of bearing design.

Tribology is the science and technology of interacting surfaces in relative motion. This article describes in detail the basic structural, operational, and interaction parameters of a tribosystem. The interaction parameters, which characterize the action of the operational parameters on the structural components in the system, consist of three important aspects: contact parameters, friction parameters, and wear parameters. These three aspects embody the complex mechanisms and relationships between the constituents of a tribosystem. The article concludes with information on the selection criteria of a material for wear applications.