Sputtering is a nonthermal vaporization process in which atoms are ejected from the surface of a solid by momentum transfer from energetic particles of atomic or molecular size. Ionized gases in plasma nitriding chambers often possess enough energy to sputter atoms from workload, fixturing, and racking surfaces that are then redeposited to the benefit or detriment of the nitriding process. This article explains how and why sputtering occurs during plasma nitriding and how to recognize and control its effects. It reviews the factors that influence the intensity of sputtering and its effects, whether positive or negative, on treated parts. It also provides recommendations for improving outcomes when nitriding titanium alloys, ferrous metals, particularly stainless steels, and components with complex geometries.

Sputtering is a nonthermal vaporization process in which the surface atoms are physically ejected from a surface by momentum transfer from an energetic bombarding species of atomic/molecular size. It uses a glow discharge or an ion beam to generate a flux of ions incident on the target surface. This article provides an overview of the advantages and limitations of sputter deposition. It focuses on the most common sputtering techniques, namely, diode sputtering, radio-frequency sputtering, triode sputtering, magnetron sputtering, and unbalanced magnetron sputtering. The article discusses the fundamentals of plasma formation and the interactions on the target surface. A comparison of reactive and nonreactive sputtering is also provided. The article concludes with a discussion on the several methods of process control and the applications of sputtered films.

In secondary ion mass spectroscopy (SIMS), an energetic beam of focused ions is directed at the sample surface in a high or ultrahigh vacuum (UHV) environment. The transfer of momentum from the impinging primary ions to the sample surface causes sputtering of surface atoms and molecules. This article focuses on the principles and applications of high sputter rate dynamic SIMS for depth profiling and bulk impurity analysis. It provides information on broad-beam instruments, ion microprobes, and ion microscopes, detailing their system components with illustrations. The article graphically illustrates the SIMS spectra and depth profiles of various materials. The quantitative analysis of ion-implantation profiles, instrumental features required for secondary ion imaging, the analysis of nonmetallic samples, detection sensitivity, and the applications of SIMS are also discussed.

This article provides information on the classification of various composites manufacturing processes based on similar transport processes. The composites manufacturing processes can be grouped into three categories: short-fiber suspension methods, squeeze flow methods, and porous media methods. The article presents an overview of the modeling philosophy and approach that is useful in describing composite manufacturing processes.

This article provides a comprehensive review and critical assessment of numerical modeling of heat and mass transfer in fusion welding. The different fusion welding processes are gas tungsten arc welding, gas metal arc welding, laser welding, electron beam welding, and laser-arc hybrid welding. The article presents the mathematical equations of mass, momentum, energy, and species conservation. It reviews the applications of heat transfer and fluid flow models for different welding processes. Finally, the article discusses the approaches to improve reliability of, and reduce uncertainty in, numerical models.

This article illustrates the momentum-trapping scheme in the incident bar and stress-reversal technique which is used to change the strain rate during the course of Hopkinson bar compression or tension experiments. It describes techniques to recover the sample after it has been subjected to a cycle of compression followed by tension or tension followed by compression with illustrations. The article provides information on the recovery dynamic testing of hard materials such as ceramics and ceramic composites and explains high-temperature dynamic recovery tests. The recovery of the sample that has been subjected to a single stress pulse allows a number of interesting applications, a few of which are reviewed.

This article examines the critical features of four key areas of modeling transport phenomena associated with casting processes. These include heat and species transport in a metal alloy, flow of the liquid metal, tracking of the free metal-gas surface, and inducement of metal flow via electromagnetic fields. Conservation equations that represent important physical phenomena during casting processes are presented. The article provides a discussion on how the physical phenomena can be solved. It provides information on a well-established array of general and specific computational tools that can be readily applied to modeling casting processes. The article also summarizes the key features of the conservation equations in these tools.

A major effort in the development of thermal spray applications has been the improvement of process reliability and predictability in response to process changes. The ability to model a process is a prerequisite to understanding and controlling it. This article provides an overview of thermal spray process modeling, as it applies to the engineering of new thermal spray equipment and coating development.

This article is a comprehensive collection of formulas, tables, and analytical solutions, addressing hundreds of heat-transfer scenarios encountered in science and engineering. It also demonstrates how to set up and solve real-world problems, while accounting for material properties, environmental variables, boundary and state conditions, and the primary modes of heat transfer: conduction, convection, and radiation.

Computational fluid dynamics (CFD) provides an efficient, alternate, virtual approach for simulating and analyzing quenching processes with an impact on component design, manufacturing process, and quality. This article provides domain insights for quenching researchers and CFD practitioners for the modeling of the industrial quenching process and for supporting the diverse multifunctional needs in an industry, ranging from primary metallurgical companies (steel, aluminum, and other alloys), original equipment manufacturers, engineering companies, captive and commercial heat treating facilities, quench system manufacturers, and quench fluid suppliers. It describes the governing differential equations for the fluid flow and heat-transfer phenomena during quenching. The article also discusses different modeling categories to determine a CFD methodology for quenching.

This article presents conservation equations for heat, species, mass, and momentum to predict transport phenomena during solidification processing. It presents transport equations and several examples of their applications to illustrate the physics present in alloy solidification. The examples demonstrate the utility of scaling analysis to explain the fundamental physics in a process and to demonstrate the limitations of simplifying assumptions. The article concludes with information on the solidification behavior of alloys as predicted by full numerical solutions of the transport equations.

This article is a comprehensive collection of formulas, tables, and analytical solutions, addressing hundreds of heat-transfer scenarios encountered in science and engineering. With detailed explanations and dimensioned drawings, the article demonstrates how to set up and solve real-world problems, accounting for material properties, environmental variables, boundary and state conditions, and the primary modes of heat transfer: conduction, convection, and radiation. The article also includes reference data and provides closed-form solutions for common heat-transfer applications such as insulated pipes, cooling fins, radiation shields, and composite structures and configurations.

This article is a comprehensive collection of fluid dynamic equations for properties of fluids, fluid statics, fluid motion, dimensional analysis, and boundary layer flow. It presents equations for analyzing problems in fluid mechanics, continuity equation, momentum equation, and energy equation for solving various problems related to fluid dynamics.

This article discusses the effects of parameters on corrosivity and explains why it is critical to examine the parameter interactions prior to capturing the synergistic effects of the parameters on corrosion. It examines the methods of internal corrosion prediction for multiphase pipelines. The article reviews methodologies to perform internal corrosion direct assessment for pipelines. Real-time monitoring techniques for assessing actual corrosion at critical locations are discussed. The article also presents the case studies for multi-technique electrochemical corrosion monitoring.

In order to model macrosegregation, one must consider convection and the partitioning of segregating elements at the dendritic length scale. This article describes microsegregation with diffusion in the solid. It presents a continuum model of macrosegregation and illustrates the simulation of macrosegregation and microsegregation.

Physical vapor deposition (PVD) coatings are harder than any metal and are used in applications that cannot tolerate even microscopic wear losses. This article describes the three most common PVD processes: thermal evaporation, sputtering, and ion plating. It also discusses ion implantation in the context of research and development applications.