This article is an atlas of fractographs that helps in understanding the causes and mechanisms of fracture of high-carbon steels and in identifying and interpreting the morphology of fracture surfaces. The fractographs illustrate the following: torsional fatigue fracture, hydrogen-embrittlement fracture, fatigue crack propagation, and corrosion fatigue of components made from high-carbon steels. The high-carbon steel components include bull gear, drive shaft, power boiler stoker grate, steel wheel, spring wire, suspension spring, automotive engine valve spring, power spring, cantilever-type spring, railroad rail, and seamless drill pipe.

In addition to failures in shafts, this article discusses failures in connecting rods, which translate rotary motion to linear motion (and conversely), and in piston rods, which translate the action of fluid power to linear motion. It begins by discussing the origins of fracture. Next, the article describes the background information about the shaft used for examination. Then, it focuses on various failures in shafts, namely bending fatigue, torsional fatigue, axial fatigue, contact fatigue, wear, brittle fracture, and ductile fracture. Further, the article discusses the effects of distortion and corrosion on shafts. Finally, it discusses the types of stress raisers and the influence of changes in shaft diameter.

This article discusses failures in shafts such as connecting rods, which translate rotary motion to linear motion, and in piston rods, which translate the action of fluid power to linear motion. It describes the process of examining a failed shaft to guide the direction of failure investigation and corrective action. Fatigue failures in shafts, such as bending fatigue, torsional fatigue, contact fatigue, and axial fatigue, are reviewed. The article provides information on the brittle fracture, ductile fracture, distortion, and corrosion of shafts. Abrasive wear and adhesive wear of metal parts are also discussed. The article concludes with a discussion on the influence of metallurgical factors and fabrication practices on the fatigue properties of materials, as well as the effects of surface coatings.

Induction hardening involves multiple processing steps of heating and quenching which presents opportunity for errors and defects. This article discusses the common problems associated with induction hardening of shafts as well as the methods to diagnose, inspect, and prevent them. In addition to the major defects such as laps and seams that remain after induction hardening, microstructural transformation, decarburization, residual stress, and grain size, as well as variations in carbon content, composition, or microstructure can also affect the hardened part.

Tempering of induction-hardened steel is a form of subcritical heat treatment, primarily carried out to increase ductility, toughness, and dimensional stability, to relieve residual stresses, and to obtain specific values of mechanical properties. This article describes tempering with emphasis on different time-temperature exposure requirements for furnace and induction tempering. It discusses two parametric methods for correlating equivalent time-temperature condition: Hollomon-Jaffe tempering correlation and Grange-Baughman tempering correlation. The article describes different methods of induction tempering, namely, single-shot, progressive or continuous, scanning, and static heating methods. The effects of induction heating variables and hardenability on tempering response are examined. The article also provides examples of how tempering affects the mechanical properties of induction-hardened steels.

Induction hardening of steel components is the most common application of induction heat treatment of steel. This article provides a detailed account of electromagnetic and thermal aspects of metallurgy of induction hardening of steels. It describes induction hardening techniques, namely, scan hardening, progressive hardening, single-shot hardening, and static hardening. The article discusses the techniques used to control the heat pattern, and provides a brief review of quenching techniques used in the induction hardening. It provides guidelines for selecting the frequency and power for induction hardening, and describes common methods for measuring case depth, such as optical and microhardness, and surface hardness. It provides information on some complications and ambiguities associated with these measurements. The article also discusses the commonly used non-destructive testing methods, namely, magnetic particle testing, ultrasonic testing, and eddy current testing to evaluate induction-hardened components.

Through detection of the wear, risk assessment can be performed, along with a related time to failure estimation through technologies such as electrical signature analysis (ESA) and motor current signature analysis. This article discusses the principle of operation of data collectors for ESA measurements and illustrates the evaluation of broken rotor bars and a broken shaft. It describes the detection of faults in bearings using ESA and provides information on the investigation of gearboxes and related components in a wind generator.

Radial forging is a process performed with four dies arranged in one plane that can act on a piece simultaneously. This article explains the types of radial forgings and describes the advantages and disadvantages of radial forging over open-die cogging/forging. The article discusses the parameters involved in product shape control. It also provides examples that illustrate the versatility and capabilities of the radial forge machine.

Scanners are the most versatile and flexible of the equipment available to the heat treating industry for induction hardening. This article provides a general overview of scanners, and describes various critical factors, including scan speeds, rotational speeds, and center total indicator runout of vertical scanners. It presents information on the frequency selection parameters for scanning applications. The article also discusses the critical parameters and production rates in specifying and developing a tooth-by-tooth hardening process.

This article describes the various types of press construction and the factors that influence the selection of mechanically or hydraulically powered machines for producing parts from sheet metal. Presses are broadly classified, according to the type of frame used in their construction, into two main groups: gap-frame presses and straight-side presses. The article describes the various components of mechanical presses and hydraulic presses. It discusses important factors, such as the size, force, energy, and speed requirements, that influence the selection of a press. The article describes the roles of automatic handling equipment that can be categorized as feeding equipment, unloading equipment, and transfer equipment. It concludes with information on the common types of high-production presses, such as dieing machines, multiple-slide machines, transfer presses, fine blanking presses, and flexible-die forming presses.