This report supplements DMIC Report 152 which is a compilation of binary and ternary phase diagrams of columbium, molybdenum, tantalum, and tungsten. Forty new binary and 80 new ternary diagrams are included, some of these being revised versions of the previously published diagrams. Included with each binary diagram and with some ternary diagrams is a short discussion listing terminal solubilities and crystal struc tures of intermediate pahses. Many of the diagrams are tentative and are subject to revision as additional data become available. (Author).

The results of a state-of-the-art survey covering niobium and 18 of its most promising alloys are presented. All data are given in tabular and graphical form covering some of the more important physical, mechanical, and metallurgical properties for each material. References are given at the conclusion of each material section.

This report presents the results of a state-of-the-art survey covering tantalum and seven of its alloys. All data are given in tabular and graphical form covering some of the more important physical, mechanical, and metallurgical properties for each material. References are given at the conclusion of each material section.

To aid in quick identification and easy location of specific technical data and information in the various reports and memoranda which have been prepared and distributed by the Defense Metals Information Center, as well as by DMIC's forerunner, the Titanium Metallurgical Laboratory, a classification by major subject matter was prepared. The classification covers reports through DMIC Report 193 and memoranda through DMIC Memorandum 183. (Author).

Various alloying additions have been discovered which render unalloyed chromium much less susceptible to low-temperature embrittlement as well as to nitridation in air at elevated temperatures. These include additions of the Group IIIA metals, magnesia, and carbides based on the Groups IVA and VA metals. Of these additions, only the carbides contribute significantly to the hot strengthening of chromium. The combination of selected carbides and solid-solution-strengthening elements such as tungsten, molybdenum, and/or tantalum, has resulted in experimental alloys which retain useful strengths at temperatures through 1316 C (2400 F). These high strengths are achieved at some sacrifice in the low-temperature ductility of chromium. Also, despite the improvements afforded in the oxidation and nitridation resistance of chromium through alloying, no alloys are available which are capable of service in long-time exposures in air above 982 C (1800 F) without suffering some property degradation.