This memorandum summarizes information on refractory materials and composites that was presented at the Thirteenth Meeting of the Refractory Composites Working Group in Seattle, Washington on July 18-20, 1966. The memorandum is based on 34 papers that were presented at the meeting. They are reviewed and discussed briefly within the framework of the following four broad areas: materials technology, process technology, specific hardware applications and tests, and evaluation techniques. Included in the section on materials technology are discussions dealing with bulk refractory materials, coated systems, and fiber-reinforced composites. The section on process technology discusses cladding and general fabrication processes. The specific hardware applications and tests cover rocket-motor components, and cladding of a probe used in the glass industry. The section on evaluation techniques covers thermal testing, and non-destructive testing. (Author).

Although a considerable amount of information concerning the applications for arc plasmas in the materials sciences is available, it is contained in literally thousands of separate manuals, technical notes, textbooks, and government and industrial reports. Each source generally deals with only one specific application or, at best, a narrow range of utilization. This book was developed to provide a comprehensive and up-to-date compilation of information in the technology of arc plasma utilization. The book is divided into two general categories: flame spraying and materials evaluation. In the flame spraying section a comprehensive review of the plasma spraying process is presented. The design and operation of plasma spraying equipment are described. Included are a description of the nature of a plasma, and the design and operation of plasma generators, powder feed systems and accessory control equip ment. The general process procedures, and associated process variables are de scribed. Particular emphasis is given to the particle heating process and the mechanisms for adherence and cohesion of coatings. Competitive flame spraying equipment is also detailed (combustion process, detonation and electric arc) and compared with the plasma spray process. A discussion and compilation of flame sprayed ceramic and metal materials, their properties and applications are also included.

The Nb program is nearing completion of laboratory tory rolling studiory materials, *Heat resistant alloys, *Sheets, Niobium alloys, Molybdenum alloys, Tantalum alloys, Tungsten alloys, Titanium alloys, Zirconium alloys, Tungsten, Powder metallurgy, Electric arcs, Manufacturing methods, Mechanical proper ies, Forging, Heat treatment, Melting, Extrusion, Deformation, Hardness, Rolling mills, Processing. Identifiers: Floturning. The Nb program is nearing completion of laboratory tory rolling studies, and a single composition for larger scale rolling studies will be selected in the near future. In the Mo program, it has been shown that true hot forging of billets to sheet bar results in higher recrystallization temperatures of TZM and Mo-0.5Ti sheet than are obtained when normal forging temperatures are used. The Ta program is in the early stages of ingot production and primary breakdown fabrication of the Ta-30Nb-7.5V alloy. Three methods of fabricating W sheet are being investigated: rolling of powder-metallurgy billets, fabrication of arc-melted ingots, and floturning of cylindrical blanks. Properties obtained on both powdermetallurgy and arc-melted tungsten sheet compare very favorably. Evaluation of the formability of Mo-alloy sheet has been delayed until sheet is available from the production program. (Author).