This article describes the surface modification treatments used to modify the tribological properties of titanium alloys. These include physical vapor deposition and thermochemical conversion treatments. The physical vapor deposition includes ion implantation, sputtering, evaporation, and ion plating surface modification treatments. The thermochemical conversion surface treatments include nitriding, carburizing, boriding, and solid lubrication.

Laser surface hardening is a noncontact process that provides a chemically inert and clean environment as well as flexible integration with operating systems. This article provides a brief discussion on the various conventional surface-modification techniques to enhance the surface and mechanical properties of ferrous and nonferrous alloys. The techniques are physical vapor deposition, chemical vapor deposition, sputtering, ion plating, electroplating, electroless plating, and displacement plating. The article describes five categories of laser surface modification, namely, laser surface heat treatment, laser surface melting such as skin melting or glazing, laser direct metal deposition such as cladding, alloying, and hardfacing, laser physical vapor deposition, and laser shock peening. The article provides detailed information on absorptivity, laser scanning technology, and thermokinetic phase transformations. It also describes the influence of cooling rate on laser heat treatment and the effect of processing parameters on temperature, microstructure, and case depth hardness.

Coatings and other surface modifications are used for a variety of functional, economic, and aesthetic purposes. Two major applications of thermal spray coatings are for wear resistance and corrosion resistance. This article discusses thermal (surface hardening) and thermochemical (carburizing, nitriding, and boriding) surface modifications, electrochemical treatments (electroplating, and anodizing), chemical treatments (electroless plating, phosphating, and hot dip coating), hardfacing, and thermal spray processes. It provides information on chemical and physical vapor deposition techniques such as conventional CVD, laser-assisted CVD, cathodic arc deposition, molecular beam epitaxy, ion plating, and sputtering.

This article focuses on transport phenomena and modeling approaches that are specific to vapor-phase processes (VPP). It discusses the VPP for the synthesis of materials. The article reviews the basic notions of molecular collisions and gas flows, and presents transport equations. It describes the modeling of vapor-surface interactions and kinetics of hetereogeneous processes as well as the modeling and kinetics of homogenous reactions in chemical vapor deposition (CVD). The article provides information on the various stages of developing models for numerical simulation of the transport phenomena in continuous media and transition regime flows of VPP. It explains the methods used for molecular modeling in computational materials science. The article also presents examples that illustrate multiscale simulations of CVD or PVD processes and examples that focus on sputtering deposition and reactive or ion beam etching.

Metallographic contrasting methods include various electrochemical, optical, and physical etching techniques, which in turn are enhanced by the formation of a thin transparent film on the specimen surface. This article primarily discusses etching in conjunction with light microscopy and describes several methods for film formation, namely, heat tinting, color etching, anodizing, potentiostatic etching, vapor deposition, and film deposition by sputtering. It provides information on the general procedures and precautions for etchants and reagents used in metallographic microetching, macroetching, electropolishing, chemical polishing, and other similar operations.

Vapor-deposition processes fall into two major categories, namely, physical vapor deposition (PVD) and chemical vapor deposition (CVD). This article describes major deposition processes such as sputtering, evaporation, ion plating, and CVD. The list of materials that can be vapor deposited is extensive and covers almost any coating requirement. The article provides a table of some corrosion-resistant vapor deposited materials. It concludes with an overview of the applications of CVD and PVD coatings and a discussion on coatings for graphite, the aluminum coating of steel, and alloy coatings for aircraft turbines, marine turbines, and industrial turbines.

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.

Ion-beam-assisted deposition (IBAD) refers to the process wherein evaporated atoms produced by physical vapor deposition are simultaneously struck by an independently generated flux of ions. This article discusses the energy utilization of this process. It describes the physical and chemical processes occurring at the film-vacuum interface during IBAD and dual-ion-beam sputtering with illustrations. The article also reviews the methods used for large-area, high-volume implementation of IBAD and the modes of film formation for IBAD. It contains a table that presents information on deposition and synthesis of inorganic compounds by IBAD and concludes with a discussion on the improved coating properties, advantages, limitations, and applications of IBAD.

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.

This article focuses on different thin-film deposition techniques used to make superconducting films and discusses the properties and advantages of high-critical-temperature and low-critical-temperature materials in a number of applications, including signal processing and analog electronic devices. The article gives a brief introduction on superconducting materials, substrates and buffer layers and discusses the major deposition techniques such as, electron-beam co-evaporation, sputtering from either a composite target or multiple sources and laser ablation. The article also describes the in-situ film growth techniques for producing atomic oxygen by radio frequency excitation or microwave discharge or with ozone.

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.