Search Results for light water reactors

Irradiation-assisted stress-corrosion cracking (IASCC) has been a topic of engineering interest since it was first reported in the 1960s, having been observed in stainless steel cladding on light water reactor fuel elements. This chapter summarizes the results of decades of investigation, showing that IASCC can essentially be defined as the intergranular cracking of austenitic alloys in high-temperature water, where both the material and its environment have been altered by radiation. Of the many interactions that can occur when metals and water are exposed to radiation, the international consensus is that the three with the greatest impact on crack growth rates are the formation of material defects, radiation-induced segregation, and chemical reactions that increase the corrosion potential of water. The chapter discusses each of these in great detail, and includes information on predictive modeling as well.

This chapter examines the stress-corrosion cracking (SCC) failure of stainless steel pipe welds in boiling water reactor (BWR) service. It explains where most of the failures have occurred and provides relevant details about the materials of construction, fabrication techniques, environmental factors, and cracking characteristics. It includes a model that accounts for the primary factors involved in intergranular SCC, namely, tensile stresses above the yield stress of the base material, a sensitized microstructure, and reactor cooling water. The chapter also provides proven remedies and mitigation techniques corresponding to a wide range of issues related to stress, sensitization, and operating conditions.

This chapter describes two types of auxiliary equipment required in most induction heating installations: cooling systems and device timers. Water- and vapor-based systems used for cooling the power supply and the induction coil are described. The chapter concludes with a brief discussion of timers, with emphasis on open-loop timing systems.

Beryllium, despite its relatively simple atomic structure, possesses a wide range of useful engineering properties. It has the highest strength-to-weight ratio and modulus of elasticity among structural metals and is an important alloy addition in copper, nickel, and aluminum alloys. It also has excellent thermal properties, low atomic mass, a small x-ray absorption cross section, and a large neutron scattering cross section. This brief introductory chapter provides an overview of the unique qualities of beryllium along with typical applications and uses.

This chapter reviews weld corrosion in three key application areas: petroleum refining and petrochemical operations, boiling water reactor piping systems, and components used in pulp and paper plants. The discussion of each area addresses general design and service characteristics, types of weld corrosion issues, and prevention or mitigation strategies.

This chapter takes a practical approach to the problem of stress-corrosion cracking (SCC) in stainless steels, explaining how different application environments affect different grades of stainless steel. It describes the causes of stress-corrosion cracking in chloride, caustic, polythionic acid, and high-temperature environments and the correlating effects on austenitic, ferritic, duplex, martensitic, and precipitation hardening stainless steels and nickel-base alloys. It also discusses the contributing effects of sensitization and hydrogen embrittlement and the role of composition, microstructure, and thermal history. Sensitization is particularly detrimental to austenitic stainless steels, and in many cases, eliminating it will eliminate the susceptibility to SCC. The chapter includes an extensive amount of data and illustrations.

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.

This chapter covers the failure modes and mechanisms of concern in hydroprocessing reactor vessels and the methods used to assess lifetime and performance. It begins with a review of the materials used in the construction of pressure-vessel shells, the challenges they face, and the factors that determine shell integrity. The discussion addresses key properties and design parameters including allowable stress, fracture toughness, the effect of microstructure and composition on embrittlement, high-temperature creep, and subcritical crack growth. The chapter also provides information on the factors that affect cladding integrity and ends with a section on life-assessment techniques.

Nickel and nickel-base alloys are specified for many applications, such as oil and gas production, power generation, and chemical processing, because of their resistance to stress-corrosion cracking (SCC). Under certain conditions, however, SCC can be a concern. This chapter describes the types of environments and stress loads where nickel-base alloys are most susceptible to SCC. It begins with a review of the physical metallurgy of nickel alloys, focusing on the role of carbides and intermetallic phases. It then explains how SCC occurs in the presence of halides (such as chlorides, bromides, iodides, and fluorides), sulfur-bearing compounds (such as H2S and sulfur-oxyanions), high-temperature and supercritical water, and caustics (such as NaOH), while accounting for temperature, composition, microstructure, properties, environmental contaminants, and other factors. The chapter also discusses the effects of hydrogen embrittlement and provides information on test methods.

Nonferrous metals are of commercial interest both as engineering materials and as alloying agents. This chapter addresses both roles, discussing the properties, processing characteristics, and applications of several categories of nonferrous metals, including light metals, corrosion-resistance alloys, superalloys, refractory metals, low-melting-point metals, reactive metals, precious metals, rare earth metals, and metalloids or semimetals. It also provides a brief summary on special-purpose materials, including uranium, vanadium, magnetic alloys, and thermocouple materials.

Organic coatings (paints and plastic or rubber linings), metallic coatings, and nonmetallic inorganic coatings (conversion coatings, cements, ceramics, and glasses) are used in applications requiring corrosion protection. These coatings and linings may protect substrates by three basic mechanisms: barrier protection, chemical inhibition, and galvanic (sacrificial) protection. This chapter begins with a section on organic coating and linings, providing a detailed account of the steps involved in the coating process, namely, design and selection, surface preparation, application, and inspection and quality assurance. The next section discusses the methods by which metals, and in some cases their alloys, can be applied to almost all other metals and alloys: electroplating, electroless plating, hot dipping, thermal spraying, cladding, pack cementation, vapor deposition, ion implantation, and laser processing. The last section focuses on nonmetallic inorganic coatings including ceramic coating materials, conversion coatings, and anodized coatings.

This chapter covers the corrosion behavior of beryllium in aqueous environments. It describes the chemical reactions that drive the corrosion process, the conditions required for equilibrium, and the factors that affect corrosion resistance. It discusses the stability of the native oxides that form on the surface of beryllium and their ability to withstand acids, bases, and corrosive agents found in rain and seawater. It explains how carbides, inclusions, ions, and impurities contribute to corrosion damage, particularly pitting, and how corrosion reduces the ductility and fracture strength of certain beryllium 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.

This chapter addresses the issue of stress-corrosion cracking (SCC) in carbon and low-alloy steels. It discusses crack initiation, propagation, and fracture in aqueous chloride, hydrogen sulfide, sulfuric acid, hydroxide, ammonia, nitrate, ethanol, methanol, and hydrogen gas environments. It explains how composition and microstructure influence SCC, as do mechanical properties such as strength and fracture toughness and processes such as welding and cold work. It also discusses the role of materials selection and best practices for welding.

This chapter describes the process steps in the production of smelter grade aluminum, the environmental issues with aluminum production, and the importance of recycling. It also provides a discussion on the refining, or Bayer, process and the smelting, or Hall-Héroult, process.

Optoelectronic components can be readily classified as active light-emitting components (such as semiconductor lasers and light emitting diodes), electrically active but non-emitting components, and inactive components. This chapter focuses on the first category, and particularly on semiconductor lasers. The discussion begins with the basics of semiconductor lasers and the material science behind some causes of device failure. It then covers some of the common failure mechanisms, highlighting the need to identify failures as wearout or maverick failures. The chapter also covers the capabilities of many key optoelectronic failure analysis tools. The final section describes the common steps that should be followed so as to assure product reliability of optoelectronic components.

This chapter discusses the types of fibers and matrix materials used in ceramic matrix composites and the role of interfacial coatings. It describes the methods used to produce ceramic composites, including powder processing, slurry infiltration and consolidation, polymer infiltration and pyrolysis, chemical vapor infiltration, directed metal oxidation, and liquid silicon infiltration.

This chapter discusses radiography methods using x-rays, gamma rays, and neutrons. It begins with a discussion on the applications and principles of radiography followed by sections providing information on the sources of radiation, classifications, and characteristics of x-ray tubes. Three primary attenuation processes of electromagnetic radiation, namely photoelectric effect, Compton scattering, and pair production, are covered. The chapter then discusses the principles of shadow formation, the process involved in the conversion of radiation into a form suitable for observation, and the characteristics of x-ray film. It provides information on various exposure factors in film radiography. The chapter provides a description of the characteristics that differentiate neutron radiography from x-ray or gamma ray radiography. The application of neutron radiography is described in terms of its advantages for improved contrast on low atomic number materials, discrimination between isotopes, or inspection of radioactive specimens.

This chapter describes some of events and developments that helped drive the commercialization of beryllium and its acceptance as an engineering material. It traces the growth of the domestic beryllium industry from its origins in the 1920s to the present time, and provides a status update on the primary beryllium producers throughout the world.