Preface

This book deals with the properties, processing, and applications of lightweight materials—aluminum, magnesium, beryllium, titanium, titanium aluminides, engineering plastics, structural ceramics, and composites with polymer, metal, and ceramic matrices. This book is intended primarily for technical personnel who want to learn more about lightweight materials. It is useful to designers, structural engineers, material and process engineers, manufacturing engineers, production personnel, faculty, and students.

The first chapter is an introduction that gives a brief history of lightweight materials development during the 20th century. Somewhat surprisingly, with the exception of ceramics, none of these lightweight materials existed in usable forms until the 20th century. The second part of the introduction gives a survey of each of the lightweight materials and their current applications.

The second through sixth chapters deal with lightweight metals. Each chapter covers the basic metallurgy, properties of the available alloys, processing, and applications. Aluminum is perhaps the most important of the lightweight metals, used in a wide range of commercial, industrial, and defense applications. Magnesium, an even lighter metal than aluminum, is used where extremely light weight is paramount. The other three metals (beryllium, titanium, and titanium aluminides) have important applications in defense and aerospace. As a result of its outstanding corrosion resistance and biocompatibility, titanium has important applications in the chemical processing industry and as implants in the human body.

Plastics are pervasive in our world—we all use plastic items every day. Although the seventh chapter covers plastics in general, the emphasis is on the so-called engineering plastics. While engineering plastics are not near as strong as structural metals, due to their very low densities, they are often competitive on a specific strength (strength/density) and specific stiffness (modulus/density) basis. However, there are certain precautions that must always be followed when using plastics in load bearing applications.

The eighth and ninth chapters cover composite materials having matrices of polymers and metals. Although fiberglass composites have been used since the 1940s, the development of new high performance fibers such as carbon fiber in the early 1960s first led to their widespread use in military aircraft. This technology has been gradually transitioned to the commercial aircraft market where high performance composites will be used for large portions of the airframes of all new commercial aircraft.

Ceramics, covered in the tenth chapter, are not modern materials. They were one of the first materials used by ancient man. However, it was not until the 1950s when structural ceramics were developed that can be used in a much wider range of applications than traditional ceramics. Due to the brittle nature of ceramics, they have been historically confined to applications that place the ceramic in compression, to keep cracks from propagating. This situation is starting to change with the development of the newer toughened ceramic materials and ceramic-matrix composites. Ceramic-matrix composites are the subject of the eleventh chapter.

The twelfth, and final chapter, covers three separate topics. First, some methodologies used in the general materials selection process are discussed. Next, there are some specific guidelines for each of the lightweight materials. The last section covers the importance of the automotive sector to the lightweight materials industries.

I would like to acknowledge the help and guidance of the editorial staff at ASM for their valuable contributions.