This publication documents Proceedings of the Symposium on Metal lurgy and Technology of Refractory Metal Alloys, held in Washington, D.C. at the Washington Hilton Hotel on April 25-26, 1968, under sponsorship of the Refractory Metals Committee, Institute of Metals Division, of the Metallurgical Society of AIME, and the National Aeronautics and Space Administration. The Symposium presented critical reviews of selected topics in refractory metal alloys, thereby contributing to an in-depth understanding of the state-of-the-art, and establishing a base line for further research, development, and application. This Symposium is fifth in a series of conferences on refractory metals, sponsored by the Metallurgical Society of AlME. Publications issuing from the conferences are valuable technical and historical source books, tracing the evolution of refractory metals from early laboratory alloying studies to their present status as useful engineering materials. Refractory metals are arbitrarily defined by melting point. A 0 melting temperature of over 3500 F was selected as the minimum for this Symposium, thus excluding chromium and vanadium, which logically could be treated with other refractory metals in Groups VA and VIA of the periodic table. The Refractory Metals Committee is planning reviews of chromium and vanadium in subsequent conferences.

The principal reasons which induced the authors to write this book and the features of the book are set forth in the preface to the Russian edition. That section of the science of metals which in Russian is called "metallovedenie" or the "physical chemistry of metals" is generally referred to in scientific and technical literature published in the English language by the term "physical metallurgy." These concepts are much broader than the term" metallography," used in the scientific and technical literature of various countries, and applied solely to research on the interrelationships of the structure and proper ties of metals and alloys. Each science must have its own subject and its own method of research. Certainly, all specialists will agree that metals and alloys, including their solid solutions, mechanical mix tures, and metallic compounds, form the subject of "physical metallurgy" or "physical chemis try of metals." The aim of this science. is to produce a theory and to elucidate the experimental relationships which ought finally to make it possible to calculate quantitatively alloys Of given properties for any working conditions and parameters.

Over 220,000 entries representing some 56,000 Library of Congress subject headings. Covers all disciplines of science and technology, e.g., engineering, agriculture, and domestic arts. Also contains at least 5000 titles published before 1876. Has many applications in libraries, information centers, and other organizations concerned with scientific and technological literature. Subject index contains main listing of entries. Each entry gives cataloging as prepared by the Library of Congress. Author/title indexes.

This report summarizes the information generated since the middle of 1961 on the chemical, physical, and mechanical properties of refractory metals that are coated with oxidation-resistant coatings of advanced-experimental or commercial status. It is a supplement to DMIC Report 162, Coatings for the Protection of Refractory Metals from Oxidation, dated November 24, 1961. Recent data on specific silicide- and aluminide- type coatings for columbium, molybdenum, tantalum, and tungsten and their alloys reflect general advances in coating quality and performance, understanding of the behavior of coated systems, and more complete realization of the problems associated with the use of coated hardware.

This report summarizes the achievements on fourteen programs that were conducted in support of the Metals Sheet Rolling Program. These included programs for developing practices to produce large sheets from two grades of unalloyed tungsten (via powder metallurgy and arc melting, respectively), as well as for the Mo-0.5Ti, Mo-0.5Ti-0.1Zr-0.03C (TZM), Cb-10W-1Zr-0.1C (D-43), Cb-10W-2.5Zr (Cb-752), and Ta-30Cb-7.5V alloys. In addition, pilot sheet-rolling programs were also carried out for the Cb-27Ta-10W-1Zr (FS-85), Cb-5Mo-5V-1Zr (B-66), Ta-7W-3Re (GE-473), and Ta-9.6W-2.4Hf-0.01C (T-222) compositions.

Results of tensile stress-strain tests and completely reversed sheet-bending fatigue tests conducted at room temperature on unnotched sheet specimens of Ta-lOW tantalum alloy, D-3l niobium alloy, pure tungsten, and Mo-0.5Ti molybdenum alloy are presented. Fatigue data from tests on similar specimens of 2024-T3 aluminum alloy and 17-7 PH stainless steel are compared with previous data from axial-load tests on larger specimens of these materials to determine whether the small size of the specimens used in this investigation produces representative results. Comparisons of the various materials on the basis of applied-stress- ultimate-strength and strength-density ratio also are presented.