Alloy 7055 is widely used in the aerospace industry in applications as plate and extrusions. This datasheet provides information on key alloy metallurgy and processing effects on fracture, mechanical, tensile, and compressive properties of this 7xxx series alloy.

This article provides useful information on the selection of steels for heat treatment in order to achieve the required hardness. It discusses the effects of alloying elements on hardenability using the Grossmann's concept, and presents a discussion on the effects of alloying elements in hot-worked and cold-drawn steels. The article focuses on the selection of carbon and alloy steels based on the function of the alloying elements, and discusses the specific effects of alloying elements in steel in a tabulated form. The depth and degree of hardening (percentage of martensite) are dictated by the engineering stress analysis. Mechanical properties of quenched and tempered steels develop similar tensile properties for all practical purposes for all compositions with the same hardness. The article also provides information on the selection of steels to meet the required hardness, and elucidates the concept of hardenability for wear resistance with the help of graphs.

This article is a comprehensive collection of tables that present information on the various thermal properties, namely, the coefficient of linear thermal expansion, thermal conductivity, and specific heat, of carbon and low-alloy steels.

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.

Surface damage from sliding contact is related to the adhesion of mating surfaces in contact. This article describes the methods for evaluation of surface damage caused by sliding contact. It defines adhesive wear in terms of asperity, cold welding, galling, scuffing, seizure, and wear coefficient. The article discusses various galling testing methods, such as button-on-block galling test, pin-on-flat galling test, and threaded connection galling test. It provides an overview of fretting wear that occurs between two tight-fitting surfaces subjected to a cyclic, relative motion of extremely small amplitude. The article also reviews the fretting rig for investigating fretting wear.

Hardenability is an expression of the propensity of steel to harden when quenched at the austenitizing temperature. It is defined in terms of the depth and distribution of alloying elements present in the steel. This article describes the selection process for steel with an emphasis on hardenability. It explains the significance of H-steels, and how they are guaranteed to meet established hardenability limits for specific temperatures and chemical compositions. The article compares hardenability curves for six series of steel and includes several charts showing composition and H-band limits for various alloy grades.

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.

Hardenability of steel is the property that determines the depth and distribution of hardness induced by quenching. Hardenability is usually the single most important factor in the selection of steel for heat-treated parts. The hardenability of a steel is best assessed by studying the hardening response of the steel to cooling in a standardized configuration in which a variety of cooling rates can be easily and consistently reproduced from one test to another. These include the Jominy end-quench test, the carburized hardenability test, and the air hardenability test. Tests that are more suited to very low hardenability steels include the hot-brine test and the surface-area-center test. The article discusses the effects of varying carbon content as well as the influence of different alloying elements. It includes charts and a table that serve as a general steel hardenability selection guide.

This article discusses the following physical properties of AISI and SAE grades of carbon and low-alloy steels: coefficients of linear thermal expansion; thermal conductivity; specific heat; and electrical resistivity.

This article is a compilation of tables that present information on austenitizing temperatures for direct-hardening carbon and alloy steels, case depth of steels for different carburizing times and temperatures, typical heat treatments for case hardening of carbon and carburizing of alloy steels, as well as direct hardening of carbon steels and alloy steels.

This article describes the heat treating (stress relieving, normalizing, annealing, quenching, tempering, martempering, austempering, and age hardening) of different types of steels, including ultrahigh-strength steels, maraging steels, and powder metallurgy steels. Tabulating the recommended temperatures for normalizing and austenitizing, it provides information on mechanism, cooling media, principal variables, process procedures, and applications of heat treating. In addition, the article gives a short note on the cold and cryogenic treatment of steel.

This article discusses the fundamentals of broaching, including broach tooth terminology, broach cutting action, and broach size. It describes two types of broaching machines: horizontal and vertical. The article illustrates three general categories of broaches: solid, shell, and insert-type. It tabulates feeds and speeds for broaching various steels with high-speed tool steels and carbide tools. The article also describes the advantages and limitations of broaching and provides a brief discussion on burnishing. The causes and prevention of broach breakage are also discussed. The article concludes with information on broach repair.

Normalizing of steel is a heat treating process that is often considered from both thermal processing and microstructural standpoints. In terms of thermal processing, normalizing is defined as heating of a ferrous alloy to a suitable temperature above the transformation range and then cooling it in air to a temperature substantially below the transformation range. This article provides information on the normalizing of carbon and alloy steels, and discusses the processes involved and the furnaces used in normalizing of steel forgings, bar and tubular products, and castings. It contains tables that list the typical normalizing temperatures for standard carbon and alloy steels and typical mechanical properties of selected carbon and alloy steels in hot-rolled, normalized, and annealed conditions.

Austenitization refers to heating into the austenite phase field, during which the austenite structure is formed. This article highlights the purpose of austenitization, and reviews the mechanism and importance of thermodynamics and kinetics of austenite structure using an iron-carbon binary phase diagram. It also describes the effects of austenite grain size, and provides useful information on controlling the austenite grain size using the thermomechanical process.

Hardenability refers to the ability of steel to obtain satisfactory hardening to some desired depth when cooled under prescribed conditions. It is governed almost entirely by the chemical composition (carbon and alloy content) at the austenitizing temperature and the austenite grain size at the moment of quenching. This article describes the Jominy end-quench test, the Grossman method, and the air hardenability test to evaluate hardenability. It also reviews the factors that influence steel hardenability and selection.