Managing corrosion continues to be a challenge for operators of modern boilers worldwide. This chapter addresses the corrosion-related problems that can occur in boilers burning municipal solid waste (MSW). It describes corrosion mechanisms associated with different environments and alloys. It also discusses corrosion protection methods for furnace waterwalls and superheater tubes in waste-to-energy boilers.

This chapter outlines the topics covered in the book and explains why and to whom the book was written. The book is intended for engineers, metallurgists, and failure analysts who work with materials and components that operate in high-temperature corrosive environments. It covers eight basic modes of high-temperature corrosion as well as the effect of external and residual stresses. It also provides an extensive amount of engineering data associated primarily with commercial alloys.

Cold spray coatings technology has the potential to provide surface enhancement for applications in sectors such as defense and aerospace, oil and gas, power generation, medical, automotive, electronics, and railways. The ability to deposit clean metallic coatings is used in applications requiring corrosion/oxidation protection, erosion/wear protection, additive manufacturing, and fabricating free forms. This chapter discusses the function, advantages, and benefits of some of these applications.

Stainless steels and nickel-base alloys are recognized for their resistance to general corrosion and other categories of corrosion. This chapter examines the effects of specific alloying elements, metallurgical structure, and mechanical conditioning on the corrosion resistance of these alloys. Some categories of corrosion covered are pitting, crevice, intergranular, stress-corrosion cracking, general, and high-temperature corrosion.

This appendix provides composition data and application-related information on a wide range of superalloys in both wrought and cast form.

This chapter focuses on various factors to be considered at design stage to minimize corrosion. It begins by providing information on design considerations and general corrosion awareness. This is followed by a description of several factors influencing materials-component failure. Details on design and materials selection, which assist in controlling corrosion, are then provided. The chapter ends with a discussion on the design factors that influence corrosion.

Alloys containing elements that form volatile or low-melting-point halides are susceptible to high-temperature corrosion attack. This chapter explains how to determine whether such phases are likely to form, and the rate at which they occur, based on thermodynamic data and phase stability diagrams. It provides an extensive amount of high-temperature corrosion data for metals and alloys in gaseous environments containing chlorine and hydrogen chloride; fluorine and hydrogen fluoride; bromine and hydrogen bromide; and iodine and hydrogen iodide.

This article examines the role of alloying in the production and use of nickel and its alloys. It explains how nickel-base alloys are categorized and lists the most common grades along with their compositional ranges and corresponding UNS numbers. It describes the role of nearly 20 alloying elements and how they influence strength, ductility, hardness, and corrosion resistance. It also addresses processing issues, explaining how alloying and intermetallic phases affect forming, welding, and machining operations.

This chapter focuses on resistance characteristics and methods of protecting different forms of high-temperature gaseous corrosion, namely high-temperature oxidation, sulfidation, carburization, hydrogen effects, and hot corrosion.

The design process is the first and most important step in corrosion control. Major savings in operating costs are possible by anticipating corrosion problems so as to provide proper design for equipment before assembly or construction begins. This chapter describes the role of the design team in producing a successful final design, general considerations in corrosion-control design, and design details that accelerate corrosion. The details that must be considered when attempting to control corrosion by design include plant/site location, plant environment, component/assembly shape, fluid movement, surface preparation and coating procedures, and compatibility, insulation, and stress considerations. Design solutions for specific forms of corrosion, namely crevice corrosion, galvanic corrosion, erosion-corrosion, and stress-corrosion cracking, are then considered. A brief section is devoted to the discussion on corrosion allowance used for steel parts subject to uniform corrosion. Finally, the chapter describes the design considerations for using weathering steels.

This chapter describes the definitions, designation, chemical composition, room-temperature properties, elevated-temperature properties, and corrosion resistance of cast high alloy steels and stainless steels. In addition, the corrosion resistance of cast corrosion-resistant alloys is also covered.

Ceramics normally have high melting temperatures, excellent chemical stability and, due to the absence of conduction electrons, tend to be good electrical and thermal insulators. They are also inherently hard and brittle, and when loaded in tension, have almost no tolerance for flaws. This chapter describes the applications, properties, and behaviors of some of the more widely used structural ceramics, including alumina, aluminum titanate, silicon carbide, silicon nitride, zirconia, zirconia-toughened alumina (ZTA), magnesia-partially stabilized zirconia (Mg-PSZ), and yttria-tetragonal zirconia polycrystalline (Y-TZP). It also provides information on materials selection, design optimization, and joining methods, and covers every step of the ceramic production process.

Sulfur is one of the most common corrosive contaminants in high-temperature industrial environments and its presence can cause a number of problems, including sulfidation. This chapter describes the sulfidation behavior of a wide range of alloys as observed in three types of industrial environments. One environment consists of sulfur vapor, hydrocarbon streams, H2S, and H2-H2S gas; sulfides are the only corrosion products that form under these conditions. Another environment consists of H2, CO, CO2, H2S, and other gases, causing the formation of oxides as well as sulfides in most alloys. The third environment, for which less data exists, contains either SO2 or O2-SO2 mixtures.

Ceramic-matrix composites possess many of the desirable qualities of monolithic ceramics, but are much tougher because of the reinforcements. This chapter explains how reinforcements are used in ceramic-matrix composites and how they alter energy-dissipating mechanisms and load-carrying behaviors. It compares the stress-strain curves for monolithic ceramics and ceramic-matrix composites, noting improvements afforded by the addition of reinforcements. It then goes on to discuss the key attributes, properties, and applications of discontinuously reinforced ceramic composites, continuous fiber ceramic composites, and carbon-carbon composites. It also describes a number of ceramic-matrix composite processing methods, including cold pressing and sintering, hot pressing, reaction bonding, directed metal oxidation, and liquid, vapor, and polymer infiltration.

This chapter discusses the effects of corrosion on boiler tube surfaces exposed to water and steam. It describes the process of corrosion, the formation of scale, and the oxides of iron from which it forms. It addresses the primary types of corrosion found in boiler environments, including general corrosion, under-deposit corrosion, microbially induced corrosion, flow-accelerated corrosion, stress-assisted corrosion, erosion-corrosion, cavitation, oxygen pitting, stress-corrosion cracking, and caustic embrittlement. The discussion is supported by several illustrations and relevant case studies.

This chapter presents the primary considerations and mechanisms for corrosion and how they are involved in the selection of materials for process equipment in petroleum refineries and petrochemical plants. In addition, specific information on mechanical properties, corrosion, sulfide stress cracking, hydrogen-induced cracking, stress-oriented hydrogen-induced cracking, hydrogen embrittlement cracking, stress-corrosion cracking, velocity-accelerated corrosion, erosion-corrosion, and corrosion control is provided.