This article describes the characteristics of three types of gas bearings, such as aerostatic bearing, precision aerodynamic bearing (PAB), and compliant aerodynamic bearing (CAB). It discusses the applications for aerostatic bearings and advantages in lubricating a bearing with a compressible gas. The article also describes the different types of aerostatic bearings, such as annular thrust bearings and orifice-compensated journal bearings. It presents a discussion on load capacity and stiffness, friction and power loss, and stability and damping of the aerostatic bearings. The article provides a discussion on the types of PAB and CAB. The types include spiral groove annular thrust bearings, cylindrical journal bearings, three-sector journal bearings, tilting-pad journal bearings, and helical-grooved journal bearings. The types of CAB include foil bearings and pressurized-membrane bearings. The article concludes with a description of factors that influence materials selection for gas-lubricated bearings.

Tin is produced from both primary and secondary sources. This article discusses the chemical compositions, production, properties, microstructure and applications of tin and tin alloys. The major tin alloys discussed here are tin-antimony-copper alloy (pewter), bearing alloy, solder alloy and other alloys containing traces of tin. Data on tin consumption in the United States is presented graphically.

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.

Direct powder rolling (DPR) is a process by which a suitable powder or mixture of powders is compacted under the opposing forces of a pair of rolling mill rolls to form a continuous green strip that is further densified and strengthened by sintering and rerolling. This article discusses the basic principle, process considerations, and advantages of DRP, and describes the application of this process in the manufacture of powder titanium and titanium alloy components. It further illustrates the complexity of the process and describes the benefits of using DRP in terms of economics and product quality.

This article discusses the processing, properties, and applications of various grades of lead and lead-base alloys with the aid of several tables and illustrations. It lists the Unified Numbering System (UNS) designations for various pure lead grades and lead-base alloys grouped according to nominal chemical composition. The properties of lead that make it useful in a wide variety of applications are also discussed. The largest usage of lead is in the lead acid storage batteries (in the grid plates, posts, and connector straps). Other applications include ammunition; cable sheathing; cast products such as type metals, terneplates, and foils; and building construction materials. Lead is also used as an alloying element in steel and in copper alloys to improve machinability and other characteristics. In many applications, lead is combined with stronger materials to make structures that have the best qualities of both materials such as the plumbum series.

Aluminum, the second most plentiful metallic element, is an economic competitor in various applications owing to its appearance, light weight, fabricability, physical properties, mechanical properties, and corrosion resistance. This article discusses the primary and secondary production of aluminum and classification system for cast and wrought aluminum alloys. It talks about various manufactured forms of aluminum and its alloys, which are classified into standardized products such as sheet, plate, foil, rod, bar, wire, tube, pipe, and structural forms, and engineered products such as extruded shapes, forgings, impacts, castings, stampings, powder metallurgy parts, machined parts, and metal-matrix composites. The article also reviews important fabrication characteristics in the machining, forming, forging, and joining of aluminum alloys. It concludes with a description of the major industrial applications of aluminum, including building and construction, transportation, consumer durables, electrical, machinery and equipment, containers and packaging, and other applications.

This article discusses the properties, primary and secondary production, product forms and applications of various grades of lead and lead-base alloys with the aid of several tables and illustrations. It lists the Unified Numbering System (UNS) designations for various pure lead grades and lead-base alloys grouped according to nominal chemical composition. The properties of lead that make it useful in a wide variety of applications are also discussed. The largest use of lead is in lead-acid storage batteries. Other applications include ammunition, cable sheathing, cast products such as type metals, terneplate, foils, and building construction materials. Lead is also used as an alloying element in steel and in copper alloys to improve machinability. The article concludes with information on the principles of lead corrosion, corrosion resistance of lead in water, atmospheres, underground ducts, soil and chemicals.

Tin is a soft, brilliant white, low-melting metal that is most widely known and characterized in the form of coating. This article discusses the primary and secondary production of tin and explains the uses of tin in coating, namely tinplating, electroplating, and hot dip coatings. It presents a short note on pure (unalloyed) tin and uses of tin in chemicals. The article also covers the compositions and uses of tin alloys which include solders, pewter, bearing alloys, alloys for organ pipes, and fusible alloys. It goes on to discuss the other alloys containing tin including battery grid alloys, type metals, copper alloys, dental alloys, cast irons, titanium alloys, and zirconium alloys. Finally, it presents a short note on the applications of tin powder and corrosion resistance of tin.

Filiform corrosion has been observed to occur under a wide range of organic coatings and proceeds with the same general characteristics on steel, aluminum, and magnesium. This article describes the standard tests for filiform corrosion, characteristics and mechanisms of filiform corrosion in steels, as well as coated aluminum and magnesium. It concludes with information on the prevention and mitigation of filiform corrosion accomplished through the adjustment of the environment and changes in the substrate and coating systems.

This article describes various procedures used in the metallographic preparation of niobium, tantalum, molybdenum, and tungsten alloys. It provides information on sectioning, grinding, mounting, polishing, and electrolytic etching as well as alternate procedures that have been used on refractory metals. The article presents and analyzes several micrographs, provides etchant formulas for various materials, and discusses the unique characteristics of rhenium and its alloys.

Microjoining with high energy density beams is a new subject in the sense that the progress of miniaturization in industry has made the desire to make microjoints rapidly and reliably a current and exciting topic. This article summarizes the current state of microjoining with both electron and laser beams. It considers the elementary physical processes such as heat and fluid flow to introduce the reader to the phenomena that affect melting, coalescence, and solidification needed for a successful microweld. The various forces driving (and resisting) fluid flow are analyzed. The article discusses the equipment suitable for microjoining and the metallurgical consequences and postweld metrology of the process. It also provides examples of developmental welds employing laser and electron beam microwelding techniques.

This article provides a background of friction-bearing failures due to overheating. The failures of locomotive axles caused by overheated traction-motor support bearings are discussed. The article also describes liquid-metal embrittlement (LME) in steel. It examines the results of various axle studies, with illustrations and concludes with information on the simulation of the LME mechanism.

This article provides information about the selection of brazing processes and filler metals and describes the brazing (heating) methods, including manual torch brazing, furnace brazing, induction brazing, dip brazing, resistance brazing and specialized brazing processes such as diffusion and exothermic brazing. The article explains joint design, filler materials, fuel gases, equipment, and fluxes in the brazing methods. The article also describes the brazing of steels, stainless steels, cast irons, heat-resistant alloys, aluminum alloys, copper and copper alloys, and titanium and titanium alloys.

The development of aluminum alloys has progressed along two tracks: heat treatable and non-heat treatable. The Aluminum Association alloy composition limits and product temper are defined for major alloying elements. This article summarizes the historical evolution of the different series of wrought aluminum alloys (1xxx to 8xxx) and discusses their applications based on the alloying system introduced by the Aluminum Association.