The Physical Metallurgy of Cobalt-base Superalloys

The Physical Metallurgy of Cobalt-base Superalloys

Author: H J Wagner

Publisher:

Published: 1962

Total Pages: 102

ISBN-13:

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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).


A Discussion of the Physical Metallurgy of the 18 Per Cent Nickel Maraging Steels

A Discussion of the Physical Metallurgy of the 18 Per Cent Nickel Maraging Steels

Author: Albert M. Hall

Publisher:

Published: 1963

Total Pages: 34

ISBN-13:

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Various aspects of the physical metallurgy of the 18 % nickel maraging steels are discussed in this report in the light of the knowledge which has thus far been accumulated on these steels. The 18 % nickel type of maraging steel was singled out for discussion because of its especially attractive combination of strength and fracture toughness, the comparative simplicity with which it can be hardened, and the relative ease with which it can be formed and joined. The highnickel maraging steels are considered to be outstanding members of a loose-knit family of agehardenable or precipitation-hardenable martensitic steels. Some comparisons and analogies are drawn among various members of this family with particular reference to the 18% nickel steels. (Author).


The Effects of Heat-treating and Testing Environments on the Properties of Refractory Metals

The Effects of Heat-treating and Testing Environments on the Properties of Refractory Metals

Author: F. F. Schmidt

Publisher:

Published: 1964

Total Pages: 36

ISBN-13:

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Studies on the effects of heat-treating and testing environments for the refractory metals have been limited primarily to the unalloyed metals and a few alloys of columbium and molybdenum. Most of this work has relied on compositional changes as a means of assesing the effects of various environments on these materials. It has been shown that all of these materials are subject to contamination or purification in various test environments. The residual gases H2, CO(or N2), and H20, constitute the major sources of contamination when testing columbium and tantalum materials in vacua. Under the same conditions, molybdenum and molybdenum alloys containing carbon and reactive-metal additions are subject to serious decarburization. Nonreactive gaseous atmospheres also cause serious changes in material chemistry, since small quantities of noxious gases are contained in the atmosphere. Several promising methods of circumventing material chemistry changes during various longtime, high-temperature exposures are being used and/or evaluated. (Author).