Alloy 2055 is an Al-Cu-Li alloy developed as a replacement for high-strength 7xxx and 2xxx alloys in applications such as fuselage stringers and floor beams. This datasheet provides information on its key alloy metallurgy and illustrates the damage tolerance of 2055-T84 extrusions and 7xxx extrusions.

This article illustrates the relationships among commonly used 2xxx series alloys. It contains tables that list values for composition limits of aluminum-lithium alloys, and aerospace alloys and their temper conditions according to primary design requirements.

Heat treating of stainless steel produces changes in physical condition, mechanical properties, and residual stress level and restores maximum corrosion resistance when that property has been adversely affected by previous fabrication or heating. This article focuses on annealing of different types of stainless steels such as austenitic, ferritic, duplex, martensitic, and precipitation-hardening, and on the heat treatment of superalloys and refractory metals. It discusses the recommended procedures for solution annealing, austenite conditioning, transformation cooling, and age tempering of precipitation-hardening stainless steels. The article also lists general recommendations for the annealing temperatures of tantalum, niobium, molybdenum, tungsten, and their alloys.

Aluminum fluxing is a step in obtaining clean molten metal by preventing excessive oxide formation, removing nonmetallic inclusions from the melt, and preventing and/or removing oxide buildup on furnace walls. This article discusses the solid fluxes and gas fluxes used in foundries. It reviews the classification of solid fluxes depending on their use and function at the foundry operation. These include cover fluxes, drossing fluxes, cleaning fluxes, and furnace wall cleaner fluxes. The article also examines the operational practices and applications of the flux injection in the foundries. It describes the applications of the aluminum fluxing such as crucible furnaces, transfer ladles, reverberatory furnaces, and holding/casting furnaces.

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.

This article reviews the bulk deformation processes for various aluminide and silicide intermetallic alloys with emphasis on the gamma titanium aluminide alloys. It summarizes the understanding of microstructure evolution and fracture behavior during thermomechanical processing of the gamma aluminides with particular reference to production scaleable techniques, including vacuum arc and cold-hearth melting, isothermal forging, conventional hot forging, and extrusion. The selection and design of manufacturing methods, in the context of processing-cost trade-offs for gamma titanium aluminide alloys, are also discussed.

Ultrasonic additive manufacturing (UAM) is a solid-state hybrid manufacturing technique that leverages the principles of ultrasonic welding, mechanized tape layering, and computer numerical control (CNC) machining operations to create three-dimensional metal parts. This article begins with a discussion on the process fundamentals and process parameters of UAM. It then describes metallurgical aspects in UAM. The article provides a detailed description of a wide range of mechanical characterization techniques of UAM, namely tensile testing, peel testing, and pushpin testing. The article ends with information on sensor embedding.

Maraging steels are highly alloyed low-carbon iron-nickel martensite steels that possess an excellent combination of strength and toughness superior to that of most carbon-hardened steels. This article provides a detailed account of the formation of martensite in maraging steels. It discusses the heat treatment of these steels, namely, aging, solution annealing, age hardening, and nitriding. Their hardening during aging has been attributed to two different mechanisms: short-range ordering and precipitation. The article concludes with a discussion on the grain refinement using thermal cycling and transformation-induced plasticity maraging methods.

This article describes the physical principles of brazing with illustrations and details elements of the brazing process. The elements of brazing process include filler-metal flow, base-metal characteristics, filler-metal characteristics, surface preparation, joint design and clearance, temperature and time, rate and source of heating, and protection by an atmosphere or flux. The article explains the different types of brazing processes: manual torch brazing, furnace brazing, induction brazing, dip brazing, resistance brazing, infrared (quartz) brazing, exothermic brazing, electron-beam and laser brazing, microwave brazing, and braze welding.

Copper steels are precipitation-strengthened steels that are designed to have a unique combination of physical and mechanical properties. This article provides an overview of copper precipitate-strengthened steels and their applications, and discusses appropriate ASTM International standards. It describes the common phases and alloying elements present in copper precipitate-strengthened steels, and reviews the influences of alloying elements on processing, phase diagrams, microstructures, and mechanical properties. The article also discusses the thermomechanical process, solutionizing heat treatment, and isothermal aging in detail. It concludes with a review of the interrelationships between heat treatments, microstructures, and mechanical properties.

Cores are separate shapes of sand that are placed in the mold to provide castings with contours, cavities, and passages that are not otherwise practical or physically obtainable by the mold. This article describes the basic principles of coremaking and the types of core sands, binders, and additives used in coremaking. It discusses the curing of compacted cores by core baking and the hot box processes. The article provides an overview of the core coatings, assembling and core setting, coring of tortuous passages, and cores in permanent mold castings and investment castings. It also discusses the design considerations in coremaking to eliminate cores and compares coring with drilling.

This article provides information on biomedical aspects such as active biological responses and the chemical environment characterizing the internal physiological milieu, as well as electrochemical fundamentals needed for characterizing corrosion fatigue (CF) and stress-corrosion cracking (SCC). It discusses some of the mechanical and electrochemical phenomena related to the in vivo degradation of materials used for biomedical applications. These materials include stainless steels, cobalt and titanium-base alloy systems, and dental amalgam. The article addresses key issues related to the simulation of the in vivo environment, service conditions, and data interpretation. The factors influencing susceptibility to CF and SCC are reviewed. The article describes the testing methodology of CF and SCC. It also summarizes findings from laboratory testing, in vivo testing and retrieval studies related to CF and SCC.

This article provides crystallographic and engineering data for single oxide ceramics, zirconia, silicates, mullite, spinels, perovskites, borides, carbides, silicon carbide, boron carbide, tungsten carbide, silicon-nitride ceramics, diamond, and graphite. It includes data on crystal structure, density, mechanical properties, physical properties, electrical properties, thermal properties, and magnetic properties.