Abstract
Already during solidification of the melt, in the aluminum alloy AA 6013 occur precipitates, which are a part of a very complex microstructure and have a significant influence on the recrystallization and fracture behaviour. The chemical composition as well as the high value of microhardness suggest that it is a quasicrystal or crystalline approximant. Convergent beam electron diffraction (CBED) and selected area diffraction (SAD) investigations in combination with the interpretation of electron backscatter diffraction (EBSD) patterns led to the conclusion that the precipitates are crystalline approximants. Their chemical composition can bedescribed with the formula Al19Fe4MnSi2 and their crystallographic point group is
Abstract
In der Aluminiumlegierung AA 6013 treten Primärteilchen auf, welche sich bereits bei der Erstarrung der Schmelze bilden. Sowohl ihre chemische Zusammensetzung als auch ihre große Härte legen die Vermutung nahe, dass es sich von der Struktur her dabei um Quasikristalle oder kristalline Approximanten handeln könnte. CBED- und SAD-Untersuchungen in Kombination mit der Interpretation von EBSD-Aufnahmen führten zu der Schlussfolgerung, dass es sich bei diesen Ausscheidungen um einen kristallinenApproximanten handelt. Dessen kristallographische Punktgruppe ist
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© 2002 Carl Hanser Verlag, München
Articles in the same Issue
- Frontmatter
- Articles/Aufsätze
- Phosphorus grain boundary diffusion and segregation in Fe–2.2 wt.% Si alloy
- Intermetallic compounds formed during the soldering reactions of eutectic Sn–9Zn with Cu and Ni substrates
- Thermal fatigue resistance in Pb-based solder alloys for electronic packaging
- Rolling and recrystallization textures in Al –Mg alloys
- Structures similar to a quasicrystal in technical aluminum alloys
- Processing map for hot working of hot rolled Mg– 11.5Li –1.5Al alloy
- Applications of computational thermodynamics
- Phase diagram of the Fe –Co –R system with R ⩽33.3 at.% Sm0.5Nd0.5
- Microstresses caused by uniaxial deformation and by mechanical surface treatments
- The influence of basic vs. rutile electrode on the composition of duplex stainless steel weldments
- Mixed mode I/III fracture toughness of Armco iron at 77 K
- Suitability assessment of replacement of conventional hot-working steels with maraging steel
- Suitability assessment of replacement of conventional hot-working steels with maraging steel
- Notifications/Mitteilungen
- Personal/Personelles
- Conferences/Tagungen
Articles in the same Issue
- Frontmatter
- Articles/Aufsätze
- Phosphorus grain boundary diffusion and segregation in Fe–2.2 wt.% Si alloy
- Intermetallic compounds formed during the soldering reactions of eutectic Sn–9Zn with Cu and Ni substrates
- Thermal fatigue resistance in Pb-based solder alloys for electronic packaging
- Rolling and recrystallization textures in Al –Mg alloys
- Structures similar to a quasicrystal in technical aluminum alloys
- Processing map for hot working of hot rolled Mg– 11.5Li –1.5Al alloy
- Applications of computational thermodynamics
- Phase diagram of the Fe –Co –R system with R ⩽33.3 at.% Sm0.5Nd0.5
- Microstresses caused by uniaxial deformation and by mechanical surface treatments
- The influence of basic vs. rutile electrode on the composition of duplex stainless steel weldments
- Mixed mode I/III fracture toughness of Armco iron at 77 K
- Suitability assessment of replacement of conventional hot-working steels with maraging steel
- Suitability assessment of replacement of conventional hot-working steels with maraging steel
- Notifications/Mitteilungen
- Personal/Personelles
- Conferences/Tagungen