Magnesium, by volume, is two-thirds the weight of aluminum and one-quarter the weight of steel. It also has good damping capacity, giving it an edge over other metals in high-vibration environments. This chapter discusses the basic metallurgy, alloy designations, compositions, and mechanical properties of cast and wrought magnesium alloys. It also describes the processes used to produce magnesium parts, the causes and effects of corrosion, and the use of protective coatings and treatments.

Corrosion is a key subject for more or less all classes of alloys that fall within the broad definition of stainless steels because these alloys were developed with the intention of preventing corrosion. This chapter provides an introduction to the fundamentals of electrochemical theory as it pertains to corrosion resistance of stainless steels. The discussion provides an overview of electrochemical reactions, Faraday's law, the Nernst equation, galvanic versus electrochemical cells, corrosion tendency, and Pourbaix diagrams.

Corrosion involves chemical reactions in equilibrium that that are understood through principles of thermodynamics. In practice, the rate at which corrosion reactions occur is the most important consideration. This chapter deals with corrosion kinetics, which allows engineers to to understand rates of corrosion. The discussion covers two kinetic processes, namely electrode reactions at the cathode and anode and conduction of ions in the electrolyte. The chapter also provides information on passivation and its effect on polarization diagrams.

This chapter explores the behavior of stainless steel in media that promote corrosion. The forms of corrosion covered are uniform corrosion, atmospheric corrosion, localized corrosion, pitting corrosion, crevice corrosion, and grain boundary corrosion. The chapter discusses the influence of material and environmental variables on stress-corrosion cracking (SCC) and the mechanisms proposed for SCC in stainless steel, comparing the mechanism of SCC with hydrogen embrittlement. In addition, it provides information on biocorrosion and microbiologically induced corrosion in ambient aqueous environments.

This chapter deals with the technology of stainless steel as it pertains to its proper use in architecture, art, and construction. It begins with an overview of the corrosion resistance of stainless steel, providing guidelines for balancing corrosion resistance, processing characteristics, and economy. This is followed by sections describing the influence of surface finish on corrosion resistance of stainless steel and reviewing some of the factors pertinent to balancing service environment, design requirements, and maintenance considerations. The chapter then discusses the various factors pertinent to important considerations in buildings, namely surface finish aesthetics, flatness, maintenance, repair, fabrication, and service considerations. It ends with a section providing information on concrete reinforcing bar.

Polymer-matrix composites are among the lightest structural materials in use today. They are also highly resistant to corrosion and fatigue and their load-carrying capabilities, such as strength and stiffness, can be tailored for specific applications. This chapter discusses the primary advantages and disadvantages of polymer-matrix composites, how they are produced, and how they perform in different applications. It describes the construction of laminates, the fibers and resins used, and the methods by which they are combined. It explains how strength, modulus, toughness, and high-temperature and corrosion behaviors are determined by the orientation, shape, and spacing of fibers, the number of plies, resin properties, and consolidation and forming methods. The chapter also covers secondary fabrication processes, such as thermoforming, machining, and joining, as well as production equipment and product forms, and include guidelines for optimizing tradeoffs when selecting fibers, resins, and production techniques.

Titanium is a lightweight metal used in a growing number of applications for its strength, toughness, stiffness, corrosion resistance, biocompatibility, and high-temperature operating characteristics. This chapter discusses the applications, metallurgy, properties, compositions, and grades of commercially pure titanium and alpha and near-alpha, alpha-beta, and beta titanium alloys. It describes primary and secondary fabrication processes, including melting, forging, forming, heat treating, casting, machining, and joining as well as powder metallurgy and direct metal deposition. It also compares and contrasts the properties of wrought, cast, and powder metal titanium products and discusses corrosion behaviors.

Stainless steels derive their name from their corrosion-resisting properties first observed in 1912. Two groups, working independently, concurrently discovered what came to be known as austenitic and ferritic stainless steels. Martensitic and precipitation-hardened stainless steels would be developed later. This chapter discusses each of these four major types of stainless steel and their respective compositions, properties, and uses. It explains how alloying, heat treating, and various hardening processes affect corrosion performance, and includes a detailed discussion on the optimization of martensitic stainless steels for cutlery applications.

This article examines the composition and properties of magnesium and its alloys. It discusses alloy and temper designations, applications and product forms, and commercial alloy systems, and explains how alloying elements affect physical and mechanical properties, processing characteristics, and corrosion behaviors.

This article discusses the general purpose of alloying and identifies some of the material properties and behaviors that can be improved by adding various elements to the base metal. It explains how alloying can make metals stronger and more resistant to corrosion and wear as well as easier to cast, weld, form, and machine. It also discusses some of the alloying techniques that have been developed to address problems stemming from dissimilarities between the base metal and alloying or inoculate material.

This chapter provides basic engineering information on aluminum alloys with an emphasis on their use in applications where weight is a significant design factor. It discusses the advantages and limitations of various types of aluminum along with their compositions, designations, and achievable strengths. It explains how some alloys are hardened through solution strengthening and cold working, while others are strengthened by precipitation hardening. It also describes production and fabrication processes such as melting, casting, rolling, forging, forming, extruding, heat treating, and joining, and includes a section on the causes and effects of corrosion and how they are typically controlled.

This chapter briefly outlines some of the basic aspects of failure analysis, describing some of the basic steps and major concerns in conducting a failure analysis. A brief review of failure types from fracture, distortion, wear-assisted failure, and environmentally assisted failure (corrosion) is also provided.

With typical alloy systems, casting is often the most convenient method by which to produce components. This is true for stainless steels, both for corrosion-resisting and for heat-resisting applications. This chapter discusses stainless steel casting alloys and their metallurgy. Foundry methods are discussed to the degree they are specific to the stainless alloys.

Beryllium is an extraordinary metal with an unusual combination of physical and mechanical properties. It has low density, high stiffness, and excellent dimensional stability. It is also transparent to x-rays and can be machined to extremely close tolerances. This chapter discusses the properties, compositions, and processing characteristics of beryllium and its alloys. It provides information on powder production and consolidation, commercial designations and grades, wrought products, and forming processes. It also discusses the issue of corrosion, the use of protective treatments and coatings, and health and safety concerns.

Failure analysis of steel welds may be divided into three categories. They include failures due to design deficiencies, weld-related defects usually found during inspection, and failures in field service. This chapter emphasizes the failures due to various discontinuities in the steel weldment. These include poor workmanship, a variety of hydrogen-assisted cracking failures, stress-corrosion cracking, fatigue, and solidification cracking in steel welds. Hydrogen-assisted cracking can appear in four common forms, namely underbead or delayed cracking, weld metal fisheyes, ferrite vein cracking, and hydrogen-assisted reduced ductility.

This article discusses the role of alloying in the production and use of common refractory metals, including molybdenum, tungsten, niobium, tantalum, and rhenium. It provides an overview of each metal and its alloys, describing the compositions, properties, and processing characteristics as well as the effect of alloying elements. It also discusses strengthening mechanisms and, where appropriate, corrosion behavior.