コバルト基の高温合金
1Department of Materials Science, Graduate School of Engineering, Tohoku University, Sendai 980-8579, Japan.
まとめ
新しいコバルトベースの超合金には,より優れた高温強度があります. これらの高度な合金は,ユニークなL1(2) 構造化合物によって強化され,次世代の材料に有望な可能性を秘めています.
科学分野:
- マテリアルサイエンス 材料科学
- メタルルジーは,金属の製造業です.
- 高温合金 高温合金
背景:
- 従来のニッケル基超合金には,極端な高温のアプリケーションで限界があります.
- 高温耐久性を高める先進的な材料の必要性は,次世代技術にとって極めて重要です.
研究 の 目的:
- 優れた高温機械特性を持つ新しいコバルト基超合金を特定し,特徴づけること.
- これらの新しい合金システムにおける強化メカニズムを調査する.
主な方法:
- コバルト基合金の金属学分析と特徴付け.
- L1(2) 構造による強化段階の識別.
主要な成果:
- 従来のニッケル基超合金よりも高い高温強度を示すコバルト基超合金が特定されました.
- L1(2) 構造の三元化合物であるガンマ'Co3(Al,Wがコバルトマトリックスに一貫して沈殿し,高温強化を提供することが判明しました.
- 同じような三元化合物であるgamma' Ir3 ((Al,W)) も同定された.
結論:
- Gamma' Co3 ((Al,W) により強化されたコバルトベースの超合金には,高温の用途に重要な利点があります.
- Gamma+gamma'構造を持つCo-Ir-Al-Wベースのシステムは,次世代の高温材料として大きな期待を示しています.
さらに関連する動画
関連する概念動画
Types of Chemical Bonds
Chemical bonding theories were pioneered by American chemist Gilbert N. Lewis. He developed a model called the Lewis model to explain the type and formation of different bonds. Chemical bonding is central to chemistry; it explains how atoms or ions bond together to form molecules. It explains why some bonds are strong and others are weak, or why one carbon bonds with two oxygens and not three; why water is H2O and not H4O.
Bonding in Metals
Metallic bonds are formed between two metal atoms. A simplified model to describe metallic bonding has been developed by Paul Drüde called the “Electron Sea Model”.
Metallic Solids
Metallic solids such as crystals of copper, aluminum, and iron are formed by metal atoms. The structure of metallic crystals is often described as a uniform distribution of atomic nuclei within a “sea” of delocalized electrons. The atoms within such a metallic solid are held together by a unique force known as metallic bonding that gives rise to many useful and varied bulk properties.
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability. Many...
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability. Many...
Metal-Ligand Bonds
The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain coordination compounds. Ions of the metals, especially the transition metals, are likely to form complexes.
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
Ferromagnetism
Materials like iron, nickel, and cobalt consist of magnetic domains, within which the magnetic dipoles are arranged parallel to each other. The magnetic dipoles are rigidly aligned in the same direction within a domain by quantum mechanical coupling among the atoms. This coupling is so strong that even thermal agitation at room temperature cannot break it. The result is that each domain has a net dipole moment. However, some materials have weaker coupling, and are ferromagnetic at lower...
Strength and Heat of Hydration
The hydration of cement is an exothermic reaction in which heat is generated as cement hydrates. This heat of hydration is critical to cement's strength development. The rate at which this heat is generated affects the temperature rise, with a majority of the heat being released early in the hydration process, half within the first three days, and about 75% within the first week.
The heat of hydration for each cement compound is significant; for instance, tricalcium aluminate (C3A) and...
The heat of hydration for each cement compound is significant; for instance, tricalcium aluminate (C3A) and...


