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 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.

This book presents the findings of experimental and theoretical (including first-principles molecular dynamics simulation) studies of nanostructured and nanocomposite metal-based materials, and nanoscale multilayer coatings fabricated by physical or chemical vapor deposition, magnetron sputtering, electrospark alloying, ionic layer absorption, contact melting, and high-current electron beam irradiation. It also discusses novel methods of nanocomposite formation, as well as the structure of the deposited films, coatings and other nanoscale materials, their elemental and phase composition, and their physical–mechanical, tribological, magnetic and electrical properties. Lastly, it explores the influence of a various surface modification methods, such as thermal annealing, pulsed laser modification, and thermomechanical and ultrasonic treatment, as well as different properties of nanostructured films.

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.

I NFORMATION ON REFRACTORY COMPOSITES FOR USE ABOVE