Preface
Most of the metals in use today have been extracted from thermodynamically stable ores. Hence, when metallic materials are exposed to the environment, they have a strong propensity to revert back to their natural, stable compounds through corrosion. For this reason, the deleterious effects of corrosion have been a concern since ancient times. Today, the wasting away of metals through corrosion is a very costly problem, and numerous studies have estimated that corrosion-related damages account for approximately 3–4% of the gross domestic product of industrialized nations. For the United States alone, the losses due to corrosion are estimated to be on the order of $500 billion per year. One of the most effective ways to prevent these losses is the use of coatings. Coatings were first used in ancient times, when they were made from egg whites, tree sap, and pitch. Today, however, polymer technology and nanotechnology allow engineers to design both functionality and aesthetics into coatings. In this modern world, almost every man-made object is protected or beautified with coatings. As a result, the worldwide coatings industry generates approximately $100 billion per year. As ever higher demands are put on coatings, requiring them to be environmentally friendly, self-cleaning, self-healing, corrosion-indicating, superdurable, and so on, the traditional coatings of yesteryear are gradually becoming obsolete, giving rise to research and development focused on intelligent coatings.
This book comprises a collection of articles written by experts in advanced coating technologies. The introductory chapter describes the fundamental electrochemical principles of metal protection using coatings. Chapter 2 discusses the significance of corrosion and its economic impact, considering a wide variety of current coatings, along with the importance of intelligent coatings. Chapter 3 reviews organic and inorganic pretreatments for metals and alloys, including the use of chromate and phosphate conversion coatings, as well as recent lanthanide-based conversion-coating compositions. In Chapter 4, we introduce economical routes for synthesizing organometallic compounds, the use of organometallic precursors in chemical vapor deposition processes to produce protective coatings, and growth mechanisms for coating applications. Chapter 5 demonstrates the effect of cerium ions on the development of self-healing coatings, and Chapter 6 covers corrosion protection systems that employ zinc-rich hybrid coatings containing polypyrrole and nanoparticles. In Chapter 7, we discuss work on vitreous porcelain enamel coatings containing europium and dysprosium, which have been developed for their luminescent properties. Chapter 8 deals with the self-healing of damaged coatings containing corrosion inhibitors in nano or micro containers. From a processing standpoint, Chapter 9 provides hard-to-find information on critical parameters involved in transitioning a coating from the laboratory to the pilot plant, and Chapter 10 considers a novel smart quasi-ceramic silicone conversion coating. We also discuss the results of various analytical techniques applied to coatings, and we compare the anticorrosion properties of the quasi-ceramic coating with other commercially available coatings. Chapter 11 explores the use of a conducting polymer as a superhydrophobic coating. Chapter 12 covers various mechanisms of corrosion inhibition using encapsulated corrosion inhibitors, and Chapter 13 discusses the utilization of thermochromic vanadium dioxide in the development of smart coatings. Microencapsulation of corrosion inhibitors in one-part coatings containing organosilane and diisocyanate is the subject of Chapter 14, while, in Chapter 15, we consider the protection of magnesium alloys using a stannate-based self-healing coating. Chapter 16 addresses the use of conducting electroactive polymers for corrosion prevention, and Chapter 17 discusses the control of corrosion in titanium-alloy biomedical implants by means of a series of protective coatings including passive films. Chapter 18 details the use of optical fiber sensors in corrosion monitoring. Chapter 19 points out the importance of waterborne resins formulated with nanoclay as protective, intelligent coatings for cultural heritage objects. Finally, the importance and applicability of Raman and FTIR spectroscopic techniques are the focus of Chapter 20.
We hope that this book provides a useful compilation of information for students from diverse scientific and engineering backgrounds. It can serve as a reference for research students and a technical guide for those from the industrial sector. The editors thank the organizers of the Technical Corrosion Collaboration (TCC), particularly Richard Hays, Deputy Director; as well as the Corrosion Policy and Oversight Office of the United States Under Secretary of Defense for Acquisition, Technology, and Logistics, which gave us an opportunity to collaborate in this area of scientific and industrial importance. We are hopeful that this book will pave new ways for innovative developments in coatings.