This book covers virtually all technical aspects related to the selection, processing, use, and analysis of superalloys. The text of this new second edition has been completely revised and expanded with many new figures and tables added. In developing this new edition, the focus has been on providing comprehensive and practical coverage of superalloys technology. Some highlights include the most complete and up-to-date presentation available on alloy melting. Coverage of alloy selection provides many tips and guidelines that the reader can use in identifying an appropriate alloy for a specific application. The relation of properties and microstructure is covered in more detail than in previous books.

Following three printings of the First Edition (1978), the publisher has asked for a Second Edition to bring the contents up to date. In doing so the authors aim to show how the newer microscopies are related to the older types with respect to theoretical resolving power (what you pay for) and resolution (what you get). The book is an introduction to students, technicians, technologists, and scientists in biology, medicine, science, and engineering. It should be useful in academic and industrial research, consulting, and forensics; how ever, the book is not intended to be encyclopedic. The authors are greatly indebted to the College of Textiles of North Carolina State University at Raleigh for support from the administration there for typing, word processing, stationery, mailing, drafting diagrams, and general assistance. We personally thank Joann Fish for word process ing, Teresa M. Langley and Grace Parnell for typing services, Mark Bowen for drawing graphs and diagrams, Chuck Gardner for photographic ser vices, Deepak Bhattavahalli for his work with the proofs, and all the other people who have given us their assistance. The authors wish to acknowledge the many valuable suggestions given by Eugene G. Rochow and the significant editorial contributions made by Elizabeth Cook Rochow.

In the spring of 1963, a well-known research institute made a market survey to assess how many scanning electron microscopes might be sold in the United States. They predicted that three to five might be sold in the first year a commercial SEM was available, and that ten instruments would saturate the marketplace. In 1964, the Cambridge Instruments Stereoscan was introduced into the United States and, in the following decade, over 1200 scanning electron microscopes were sold in the U. S. alone, representing an investment conservatively estimated at $50,000- $100,000 each. Why were the market surveyers wrongil Perhaps because they asked the wrong persons, such as electron microscopists who were using the highly developed transmission electron microscopes of the day, with resolutions from 5-10 A. These scientists could see little application for a microscope that was useful for looking at surfaces with a resolution of only (then) about 200 A. Since that time, many scientists have learned to appreciate that information content in an image may be of more importance than resolution per se. The SEM, with its large depth of field and easily that often require little or no sample prepara interpreted images of samples tion for viewing, is capable of providing significant information about rough samples at magnifications ranging from 50 X to 100,000 X. This range overlaps considerably with the light microscope at the low end, and with the electron microscope at the high end.