This article introduces thermal spray coatings and describes the various types of coating processes and coating devices, including the flame spray, electric-arc spray, plasma spray, transferred plasma arc, high-velocity oxyfuel, and detonation gun. It provides information on the surface preparation methods and finishing treatments of coated parts. The article also explains the tests to evaluate the coating quality and the effects of coating structures and mechanical properties on coated parts. It concludes with a discussion on the uses of thermal spray coatings.

A sacrificial coating applied to a steel substrate can add 20 years or more of life to the substrate, depending on its thickness and composition. Different techniques to apply sacrificial coatings offer various characteristics that contribute to corrosion resistance. This article discusses thermal spray, hotdipping, and electroplating processes used to apply coatings in steel structures. It describes the corrosion attributes of the resulting coatings and discusses the methods of protecting steel from corrosion using aluminum and zinc coatings.

Thermal spray coatings (TSCs) are surface coatings engineered to provide wear-, erosion-, abrasion-, and corrosion-resistant coatings for original equipment manufacture and for the repair and upgrading of in-service equipment. This article presents an overview of five thermal spray processes and the specific flame and arc spray processes used to preserve large steel components and structures. It describes the TSC selection guide and an industrial process procedure guide for applying aluminum and zinc TSCs onto steel.

Ceramic coatings are applied to metals to protect them against oxidation and corrosion at room temperature and at elevated temperatures. This article provides a detailed account of the factors to be considered when selecting a ceramic coating and describes the characteristics of various coating materials, namely, silicate glasses, oxides, carbides, silicides, and cermets. It reviews ceramic coating methods: brushing, spraying, dipping, flow coating, combustion flame spraying, plasma-arc flame spraying, detonation gun spraying, pack cementation, fluidized-bed deposition, vapor streaming, troweling, and electrophoresis. The article also includes information on the evaluation of the quality of ceramic coatings.

This article provides a general technical description of thermal spray coatings used for corrosion protection in atmospheric and aqueous environments. It further discusses two basic coating approaches of corrosion protection, namely, the sacrificial coating of thermal spray aluminum (TSA) and thermal spray zinc (TSZ), and the barrier-type coating of corrosion-resistant materials. The emphasis is on sacrificial coatings. The article describes the steps involved in the application of TSA and TSZ: surface preparation, coating deposition, and postspray treatment. It discusses their field exposure tests and application history. The article also contains helpful information on the dense barrier coatings by high-velocity spraying processes along with their corrosion performance.

This article presents the major thermal spray processes and their subsets, presenting each of the commercially significant processes together with some of their important variations. Each process is presented along with the attributes that influence coating structure and performance. The article summarizes the essential equipment components and necessary controls. The various thermal spray processes are conventional flame spray, detonation gun, high-velocity oxyfuel spray, electric arc spray, and plasma arc spray. Other processes, such as cold spray, underwater plasma arc spray, and extended-arc and other high-energy plasma arc spray, are also considered.

This article provides an overview of key abradable thermal spray coating systems based on predominant function and key design criteria. It describes two families of coatings which have evolved for use at higher temperature: flame (combustion)-sprayed abradable powders and atmospheric plasma-sprayed abradable powders. Three classic examples of flame spray abradables are nickel-graphite powders, NiCrAl-bentonite powders, and NiCrFeAl-boron nitride powders. The article provides information on various abradable coating testing procedures, namely, abradable incursion testing; aging, corrosion, thermal cycle and thermal shock testing; hardness testing; and erosion resistance testing.

This article describes the technology of thermal spraying with regard to tribological applications. It introduces the basics of tribology and presents the fundamentals of thermal spraying and the relevant process variants and suitable materials. Specific application areas are described regarding the different forms of elementary movement in the corresponding tribological system. The article provides an overview of thermal spray coatings and possible uses for friction and wear control, besides operating as corrosion protection and a thermal barrier. The article provides examples that illustrate how tribological performance can be improved.

This article provides an overview of thermal spray processes. It describes the microstructural character of thermal spray coatings as well as the criteria for coating selection. The optimization, parameterization, and surface preparation and treatments for the thermal spray coatings are also discussed. The article illustrates the adhesion of polymer coatings and the thermal spray process used to remove lead-base paint. It provides information on the specifications, standardization, and guidelines for thermal spray applicators.

Thermal spray is a generic term for a group of coating processes used to apply metallic, ceramic, cermet, and some polymeric coatings for a broad range of applications. This article provides a brief description of commercially important thermal spray processes, namely, powder-fed flame spray, wire- or rod-fed flame spray, electric arc spray, plasma arc spray, vacuum plasma spray, high-velocity oxyfuel spray, detonation gun deposition, and cold spray, and their advantages. It provides details on the microstructural characteristics of thermal spray coatings. The article also presents information on a wide variety of materials that can be thermal sprayed, such as metals, ceramics, intermetallics, composites, cermets, polymers, and functionally gradient materials. Tables are included, which list the thermal spray processes and coating properties of importance for various industrial applications.

This article begins with a description of the advantages and disadvantages of thermal spraying. It provides a discussion on the importance of substrate processing prior to coating and the role of undercutting in repair. The article reviews the steps for substrate preparation, namely, cleaning, roughening, masking, and preheating. Information on the equipment and process variables of dry abrasive grit blasting are also provided. The article describes the roles of spray stream and the spray pattern for all thermal spray processes. It discusses the defects arising from poor temperature control and from the variables influencing the manipulation of the spray torch. The article concludes with helpful information on calculating the process efficiency of thermal spraying.

Significant expansion of thermal spray technology occurred with the invention of plasma spray, detonation gun, and high-velocity oxyfuel (HVOF) deposition technologies. This article provides a brief history of the major initiating inventions/developments of thermal spray processes. It provides information on feedstock materials developed for specific thermal spray processes.

Corrosion of marine- and land-based infrastructure is of major concern and its control forms an important objective. Thermal spray coatings (TSCs) are widely used for corrosion protection. This article focuses on two types of TSCs: cathodic or noble coatings and anodic or sacrificial coatings. It describes the factors affecting the performance of sacrificial TSCs in atmospheric and immersion environments. The article provides information on the applications of sacrificial TSCs, non-sacrificial coatings, and sealants/top coats, and exemplifies the use of sacrificial TSCs on structures for corrosion protection.

This article is a brief guide to information sources on thermal spray technology. The sources provided by ASM International and the Thermal Spray Society (TSS) include magazines and journals as well as reference books, including the ASM Handbook series, conference proceedings, newsletters, education courses, and videos. The article provides information on the specifications, standards, and quality control for coatings.