PREFACE TO THE THIRD EDITION fracture mechanisms in composites and quantitative fractography have been added to Chapter 7 and the section on microvoid coalescence was updated. Chapter 8 contains new discussion of fracture toughness measurements in ceramics based on microhard- ness indentation test methods. JIc test procedures are updated. a discussion of impact esting in polymers has been added to Chapter 9 Chapter 10 now begins with expanded coverage of generic toughening mechanisms found in metals, plastics, and ceramics, and their respective composites. The section on mechanical fibering has been moved from Chapter 4 to Chapter 10 and is included with consideration of fracture toughness anisotropy. Sections on toughness in various material groups have been streamlined and updated and now include treatment of the toughness of composites. New sections on liquid metal embrittlement and EAC of polymeric solids have been added to Chapter 1l and recent Keac test methods are presented. The subject of fatigue has been updated and expanded in Chapters 12 and 13 and sections on the fatigue of composites have been added to both chapters. Other new sections in Chapter 12 include discussions of the Bauschinger effect, rainflow- counting methods to account for damage during random cyclic loading, and expanded coverage of the macrofractography of fatigue fracture surfaces. Parts of Chapter 13 have been condensed to achieve a better balance of topic coverage and other sections have been updated(especially the topics concerming the growth of short cracks and the infuence of load interactions on FCP); a new section on the fatigue of ceramics has been added. Finally, additional failure analysis case histories are briefly discussed a The many changes and additions made in the third edition of this book benefited nd other topics are updated in Chapter 14 greatly from the considerable support of many individuals who critically evaluated he strengths and weaknesses of the previous edition, reviewed sections of new ma terial, and provided advanced copies of their manuscripts and original photograp These individuals include R. Queeney, N. S. Stoloff, C. E. Price, L. L. Clements, D B. williams, G. A. Miller, R. Landgraf, R Jaccard, J. A. Manson, E. E. Underwood, w.A. Herman, T. Pecorini, T. Clark, R Marissen, S.Suresh, R.Arsenault, A.Yee R. Benn, J. Weber, E. Thompson, A. G. Evans, R. O Ritchie, B. Smith, A Benscoter R. Bucci, T Crooker W. Hoffelner, and J. Mecholsky. My apologies to those whom I may have inadvertently failed to mention The manuscript was typed with great care and dedication by betty Zdinak.Addi tional production assistance was rendered by Andrea Weiss, william Herman, Sharon Siegler and Kenneth Vecchio--I thank them all My wife Linda and children, Michelle and Jason, persevered once again. Their patience and understanding was exceptional and greatly appreciated Richard w. Hertzberg