This article discusses the effect of thread design, preload, tightening, and mean stress on the fatigue strength of bolt steel. It describes the factors influencing fatigue failures in cold-driven and hot-driven riveted joints. The factors affecting the fatigue resistance of bolted friction joints are also discussed. The article reviews stress concentrations in pin joints and discusses stress-intensity factors for mechanically fastened joints.

Total joint replacement in orthopedic surgery can be achieved by excision, interposition, and replacement arthroplasty. This article details the most common materials used in total replacement synovial joints: metals, ceramics, and ultrahigh molecular weight polyethylene (UHMWPE). The principal physical properties and tribological characteristics of these materials are summarized. The article discusses pin-on-disk experiments and pin-on-plate experiments for determining friction and wear characteristics. It explains the use of various types of joint simulators, such as hip joint simulators and knee joint simulators, to evaluate the performance of engineering tribological components in machine simulators. The article concludes with a section on the in vivo assessment of total joint replacement performance.

This article discusses the development of a welding procedure for friction stir welding (FSW), including the process of defining a preliminary procedure, the optimization of parameters, the development of supporting data, and other key features to ensure a successful procedure. The critical features of FSW tool design, initial process parameters, systematic welding trials, and robustness testing are reviewed. The article provides information on the common features of welding procedure qualification. It also includes a table that lists the procedures used in the production of sound friction stir welds in various aluminum alloys.

This article compares and contrasts mechanical joining techniques used in the manufacture of aluminum assemblies, including seaming, swaging, flanging, crimping, clinching, dimpling, interference and snap fits, and interlocking joints. It provides basic illustrations of the various methods and summarizes the advantages and disadvantages of each. The article also discusses the use of staples, nails, rivets, and threaded fasteners and provides relevant property and performance data.

This article discusses different types of mechanical fasteners, including threaded fasteners, rivets, blind fasteners, pin fasteners, special-purpose fasteners, and fasteners used with composite materials. It describes the origins and causes of fastener failures and with illustrative examples. Fatigue fracture in threaded fasteners and fretting in bolted machine parts are also discussed. The article provides a description of the different types of corrosion, such as atmospheric corrosion and liquid-immersion corrosion, in threaded fasteners. It also provides information on stress-corrosion cracking, hydrogen embrittlement, and liquid-metal embrittlement of bolts and nuts. The article explains the most commonly used protective metal coatings for ferrous metal fasteners. Zinc, cadmium, and aluminum are commonly used for such coatings. The article also illustrates the performance of the fasteners at elevated temperatures and concludes with a discussion on fastener failures in composites.

This article first provides an overview of the types of mechanical fasteners. This is followed by sections providing information on fastener quality and counterfeit fasteners, as well as fastener loads. Then, the article discusses common causes of fastener failures, namely environmental effects, manufacturing discrepancies, improper use, or incorrect installation. Next, it describes fastener failure origins and fretting. Types of corrosion in threaded fasteners and their preventive measures are then covered. The performance of fasteners at elevated temperatures is addressed. Further, the article discusses the types of rivet, blind fastener, and pin fastener failures. Finally, it provides information on the mechanism of fastener failures in composites.

This article focuses on the factors to be considered for selecting fasteners for joining carbon fiber composites. These considerations include corrosion compatibility, fastener materials, strength, stiffness, head configurations, importance of clamp-up, hole fit, and lightning protection.

A key differentiator between friction stir welding (FSW) and other friction welding processes is the presence of a nonconsumable tool in FSW, often referred to as a pin tool to differentiate it from other tooling associated with the process. This article discusses materials for friction stir welding (FSW) pin tools, various tool geometries that have been used, designs for specific applications, predicting and measuring tool performance, and other considerations in FSW pin tool design. The tool materials include tool steels, superalloys, refractory metals, carbides and ceramics, and superabrasives.

Fretting is a special wear process that occurs at the contact area between two materials under load and subject to slight relative movement by vibration or some other force. This article focuses on measures to avoid or minimize crack initiation and fretting fatigue. It lists the factors that are known to influence the severity of fretting and discusses the variables that contribute to shear stresses. These variables include normal load, relative displacement (slip amplitude), and coefficient of friction. The article describes the general geometries and loading conditions for fretting fatigue. It presents the types of fretting fatigue tests and the effect of variables on fretting fatigue from different research test programs. The article also lists the general principles and practical methods for the abatement or elimination of fretting fatigue.

Fretting is a special wear process that occurs at the contact area between two materials under load and subject to slight relative movement by vibration or some other force. During fretting fatigue, cracks can initiate at very low stresses, well below the fatigue limit of nonfretted specimens. This article describes the mechanisms of fretting and fretting fatigue; stress analysis, modeling, and prediction of fretting fatigue; fretting fatigue testing; and fretting prevention methods. Three general geometries and loading conditions for fretting fatigue, along with their remedies, are reviewed.

This article discusses the fundamentals of friction stir welding (FSW) and presents governing equations and an analytical solution for heat transfer. It provides the solutions for structural distortion in FSW. The article describes various techniques that have been adopted to solve the equations and simulate the FSW process. The techniques include modeling without convective heat transfer and modeling with convective heat transfer in a workpiece. The article concludes with information on active research topics in the simulation of FSW.

The quality of brazed stainless steel joints depends on the selection of the brazing process, process temperature, filler metal, and the type of protective atmosphere or flux. This article provides a detailed discussion on the applicability and brazeability of stainless steel and lays an emphasis on the selection of suitable filler metal, brazing processes, and its corresponding furnace atmosphere for brazing different grades of stainless steel. The types of brazing processes include torch brazing, furnace brazing in different atmospheres (dissociated ammonia, dry hydrogen, and vacuum atmosphere), dip brazing in salt bath, and high-energy-beam brazing. A complete list of the typical compositions and properties of standard brazing filler metals for brazing stainless steel is also provided.

Friction stir welding (FSW) involves plastic deformation at high strain rates and elevated temperatures with resultant microstructural changes leading to joining. This article provides a link between deformation and FSW process parameters and summarizes the results of experimental temperature measurements during FSW of various metals. It considers the physical explanation of the heat input during FSW and the possible methods of their estimation. The article presents the experimental results of two analytical models, supplemented by experimental/numerical flow models on material flow during FSW. The types of defects, processing parameters affecting the generation of these defects, and results of theoretical models and simulations to understand the formation and control of defects during FSW are discussed. The article concludes with information on the microstructure and its distribution produced during FSW.