This article describes the principal cladding processes and methods for calculating properties of clad metals. It reviews the designing processes of clad metals to achieve specific requirements. The article discusses six categories of clad metal systems designed for corrosion control: noble metal clad systems, corrosion barrier systems, sacrificial metal systems, transition metal systems, complex multilayer systems, and clad diffusion alloys.

Diffusion welding involves minimal pressurization, but relatively high temperatures and long periods of time. This article discusses the process variants of diffusion welding: solid-phase and liquid-phase processes. It describes the diffusion welding of carbon and low-alloy steels, high-strength steels, stainless steels, and aluminum-base alloys. The article provides a discussion on dissimilar metal combinations, such as ferrous-to-ferrous combinations, nonferrous-to-nonferrous combinations, ferrous-to-nonferrous combinations, and metal-ceramic joining.

This article describes the solid-phase and liquid-phase processes involved in diffusion bonding of metals. It provides a detailed discussion on the diffusion bonding of steels and their alloys, nonferrous alloys, and dissimilar metals. Ceramic-ceramic diffusion welding and a variation on this process in which ceramic powder compacts are simultaneously sintered and bonded are also discussed.

This article provides an overview of the finite-element-based analyses (FEA) of advanced composite structures and highlights key aspects such as the homogenization of materials properties and post-processing of numerical results. It discusses the analysis of composite structures based on micromechanics and macromechanics. The article describes the FEA of 3-D solid elements, 2-D cylindrical shell elements, and 1-D beam elements. It contains a table that lists the commercially available finite element codes related to the analysis of fibrous composite materials. The article presents classical examples of the mechanics of composite materials to illustrate the aspects of multilayered composite structures.

This article presents a general description of pulsed-laser deposition. It describes the components of pulsed-laser deposition equipment. The article also discusses the effects of angular distribution of materials. Finally, the article reviews the characteristics of high-temperature superconductors and ferroelectric materials.

This article addresses surface cleaning, finishing, and coating operations that have proven to be effective for molybdenum, tungsten, tantalum, and niobium. It describes standard procedures for abrasive blasting, molten caustic processing, acid cleaning, pickling, and solvent and electrolytic cleaning as well as mechanical grinding and finishing. The article also provides information on common plating and coating methods, including electroplating, anodizing, and oxidation-resistant coatings.

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.

Electroless, or autocatalytic, metal plating is a nonelectrolytic method of deposition from solution that can be plated uniformly over all surfaces, regardless of size and shape. The plating's ability to plate onto nonconductors is an advantage that contributes to the choice of electroless copper in various applications. This article provides information on the bath chemistry and deposit properties of electroless copper and discusses the applications of electroless copper plating, such as printed wiring boards, decorative plating-on-plastic, electromagnetic interference shielding, and hybrid and other advanced applications. It describes two commercial processes, pretreatment and post-treatment. The article reviews the solutions used, controls and control equipment, and performance criteria of electroless copper plating. It concludes with information on the environmental and safety issues associated with electroless copper plating.

Ceramic materials serve important insulative, capacitive, conductive, resistive, sensor, electrooptic, and magnetic functions in a wide variety of electrical and electronic circuitry. This article focuses on various applications of advanced ceramics in both electric power and electronics industry, namely, dielectric, piezoelectric, ferroelectric, sensing, magnetic and superconducting devices.

The refractory metals include niobium, tantalum, molybdenum, tungsten, and rhenium. They are readily degraded by oxidizing environments at moderately low temperatures. Protective coating systems have been developed, mostly for niobium alloys, to permit their use in high-temperature oxidizing aerospace applications. This article discusses the properties, processing, applications, and classes of refractory metals and its alloys, namely molybdenum, tungsten, niobium, tantalum and rhenium. It also provides an outline of the coating processes used to improve their oxidation resistance.

Ceramic-forming processes usually start with a powder which is then compacted into a porous shape, achieving maximum particle packing density with a high degree of uniformity. This article compares and contrasts several forming processes, including mechanical consolidation, dry pressing, cold isostatic pressing, slip casting, tape casting, roll compaction, extrusion, and injection molding. It describes the advantages, equipment and tooling, and material requirements of green machining, the machining of ceramics in an unfired state with the intent of producing parts as close to as possible to their final shape. The article also provides useful information on drying methods, shrinkage, and defects as well as the removal of organic processing aids such as dispersants, binders, plasticizers, and lubricants.

This article discusses the process considerations and deposit properties of nickel plating. It describes the Watts solution and the anode materials used. The article focuses on the nickel plating processes used for decorative, engineering, and electroforming purposes. It provides information on the quality control of nickel plating. It concludes with a review of the environmental, health, and safety considerations associated with nickel plating.

Cemented carbides belong to a class of hard, wear-resistant, refractory materials in which the hard carbide particles are bound together, or cemented, by a ductile metal binder. Cermet refers to a composite of a ceramic material with a metallic binder. This article discusses the manufacture, composition, classifications, and physical and mechanical properties of cemented carbides. It describes the application of hard coatings to cemented carbides by physical or chemical vapor deposition (PVD or CVD). Tungsten carbide-cobalt alloys, submicron tungsten carbide-cobalt alloys, and alloys containing tungsten carbide, titanium carbide, and cobalt are used for machining applications. The article also provides an overview of cermets used in machining applications.

This article discusses the fundamentals of electroplating processes, including pre-electroplating and surface-preparation processes. It illustrates the four layers of a plating system, namely, top or finish coat, undercoat, strike or flash, and base material layers. The article describes various plating methods, such as pulse electroplating, electroless plating, brush plating, and jet plating. It reviews the types of electrodeposited coatings, including hard coatings and soft coatings. The article also details the materials available for electroplating, including electroplated chromium, electroplated nickel, electroless (autocatalytic) nickel, electroless nickel composite coatings, electroplated gold, and platinum group coatings. These are specifically tailored toward plated coatings for friction, lubrication, and wear technology. The article concludes with a discussion on the common issues encountered with electroplating.

This article focuses on the methods that are being developed for detecting and monitoring corrosion: electrochemical methods, electromagnetic or sound wave methods, fiber-optic technology, fluorescence methods, and the Diffracto Sight method. It reviews the importance of data management and the Corrosion Expert System. It concludes with information on the simulation and modeling for incorporating the mechanisms of corrosion prevention into military hardware systems design and operation.

This article provides an overview of the implementation of wire embedding with ultrasonic energy and thermal embedding for polymer additive manufacturing, discussing the applications and advantages of the technique. The mechanical and electrical performance of the embedded wires is compared with that of other conductive ink processes in terms of electrical conductivity and mechanical strength.

This article focuses on the electroless gold plating technique, describing the advantages and limitations, applications, and properties of plated deposits. It also reviews process variables of the technique, including gold concentration, reducing agent, agitation, and contaminants.

This article presents a summary of the current and new materials and processing techniques for thermal barrier coatings (TBCs) and environmental barrier coatings (EBCs). Different thermal spraying and postspraying processing techniques are required to produce coatings with optimal performance. For TBCs and EBCs, the elastic modulus, mechanical strength, and toughness values are extremely important in predicting failure behavior under stress and strain conditions, mainly for modeling purposes. Sand and/or volcanic ash particles are molten in the hot zones of turbines and deposited over TBCs and EBCs. They form calcium-magnesium-aluminosilicate (CMAS) glassy deposits.

This article discusses bismaleimide (BMI) chemistry and the use of BMI in composites. An analysis of the applications illustrates how the advantages of BMIs have been exploited and perhaps suggests how these advantages might be extended to other applications. The article describes the mechanical properties of BMI composites. BMIs suitable for resin transfer molding processing are provided. The article concludes with information on the elevated-temperature applications of 5250-4 BMI system.

This article describes the coating materials, surface-preparation requirements, and application techniques used to protect underground pipelines. It provides a valuable insight into the types of polymer-based coatings that are both cost-effective and widely accepted in the pipeline industry.