This report is the third of a series which will periodically summarize the status of the various contracts involved in the Department of Defense Refractory Metals Sheet Rolling Program. Under this program, selected candidate materials are being carried through one or more of the following consecutive phases: Phase I, development of a sheet-production practice; Phase II, establishment of minimum design data; and Phase III, evaluation of sheetfabrication characteristics. To the present time, 13 contracts have been funded or planned in support of the Phase I, II, and III activities. This report summarizes the status of each of these individual contracts as of November 1, 1964. The first section describes the overall program of the Department of Defense Refractory Metals Sheet Rolling Program. Following, in the order of their discussions, are sections dealing with fabricable molybdenum alloys, unalloyed tungsten, columbium alloys, and tantalum alloys. (Author).

Government-sponsored tungsten research and development efforts encompass a broad rage of technological activities. Typifying the extreme limits of efforts since January, 1960, studies have ranged from preparation of unalloyed metal to development of high-integrity fabricated shapes of tungsten-base materials. Nine major areas outline the broad over-all effort, and each is summarized within this report by brief technical discussions of 104 separate studies on 79 research programs. Included are preparation of metal, consolidation, primary and secondary working, joining, fabrication and performance of rocket nozzles, oxidation and other high-temperature reactions, protective coatings, properties, and physical metallurgy.

A detailed picture is presented of the physical and chemical phenomena that affect the behavior of cobalt-base superalloys. Solid-solution strengthening is obtained from the high-melting metallic elements molybdenum, tungsten, tantalum, and columbium. These elements also participate in precipitation reactions involving their carbides. Precipitation of intermetallic compounds such as Ni3Ti is an important process in cobalt alloys containing appreciable amounts of nickel and titanium. The relationships among microstructure, heat treatment, and mechanical properties of the important commercial alloys are considered, and whenever possible, explained on the basis of the physical and chem cal processes that occur. (Author).