The Sagamore Army Materials Research Conferences have been held in the beautiful Adirondack Mountains of New York State since 1954. Organized and conducted by the Army Materials and Mechanics Research Center (Watertown, Massachusetts) in cooperation with Syracuse University, the Conferences have focused on key issues in Materials Science and Engineering that impact directly on current or future Army problem areas. A select group of speakers and attendees are assembled from academia, industry, and other parts of the Department of Defense and Government to provide an optimum forum for a full dialogue on the selected topic. This book is a collection of the full manuscripts of the formal presentations given at the Conference. The emergence and use of nontraditional materials and the excessive failures and reject rates of high technology, materials intensive engineering systems necessitates a new approach to quality control. Thus, the theme of this year's Thirty-First Conference, "Materials Characterization for Systems Performance and Reliability," was selected to focus on the need and mechanisms to transition from defect interrogation of materials after production to utilization of materials characterization during manufacturing. The guidance and help of the steering committee and the dedicated and conscientious efforts of Ms. Karen Ka100stian, Con­ ference Coordinator, and Mr. William K. Wilson, and Ms. Mary Ann Holmquist are gratefully acknowledged. The continued active interest and support of Dr. Edward S. Wright, Director, AMMRC; Dr. Robert W. Lewis, Associate Director, AMMRC; and COL L. C. Ross, Commander/ Deputy Director, AMMRC; are greatly appreciated.