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A Novel Biaxial Testing Apparatus for the Determination of Forming Limit under Hot Stamping Conditions
Published on: April 4, 2017
Cobalt-base high-temperature alloys.
1Department of Materials Science, Graduate School of Engineering, Tohoku University, Sendai 980-8579, Japan.
Science (New York, N.Y.)
|April 8, 2006
Summary
New cobalt-base superalloys exhibit superior high-temperature strength. These advanced alloys are strengthened by a unique L1(2) structure compound, offering promising potential for next-generation materials.
Area of Science:
- Materials Science
- Metallurgy
- High-Temperature Alloys
Background:
- Conventional nickel-base superalloys face limitations in extreme high-temperature applications.
- The need for advanced materials with enhanced high-temperature strength is critical for next-generation technologies.
Purpose of the Study:
- To identify and characterize novel cobalt-base superalloys with superior high-temperature mechanical properties.
- To investigate the strengthening mechanisms in these new alloy systems.
Main Methods:
- Metallurgical analysis and characterization of cobalt-base alloys.
- Identification of strengthening phases with the L1(2) structure.
Main Results:
- Cobalt-base superalloys demonstrating higher high-temperature strength than conventional nickel-base superalloys were identified.
- A ternary compound, gamma' Co3(Al,W), with the L1(2) structure was found to precipitate coherently in the cobalt matrix, providing high-temperature strengthening.
- A similar ternary compound, gamma' Ir3(Al,W), was also identified.
Conclusions:
- Cobalt-base superalloys strengthened by gamma' Co3(Al,W) offer significant advantages for high-temperature applications.
- Co-Ir-Al-W-base systems with gamma+gamma' structures show great promise as next-generation high-temperature materials.
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