G. Sauthoff - Academia.edu (original) (raw)

Papers by G. Sauthoff

Materials Science and Engineering: A, 2011

The influence of hot-deformation and tempering temperature on the microstructure evolution of a 1... more The influence of hot-deformation and tempering temperature on the microstructure evolution of a 12%Cr heat resistant steel during short-term creep at 80-250 MPa and 650 • C was investigated. Quantitative determination of dislocation density and sub-grain size in the initial microstructure and after creep was investigated by STEM-HAADF. A correlation between microstructure evolution and creep response is established. All crept samples showed a significant increase of sub-grain size and a reduction of dislocation density. Hot-deformed samples showed better creep strength than non hot-deformed samples due to homogenization of the microstructure. The tempering temperature affected the dislocation density and the sub-grain size evolution, influencing the creep behavior.

Gegenüber warmfesten austenitischen Metalllegierungen zeichnen sich warmfeste ferritische Legieru... more Gegenüber warmfesten austenitischen Metalllegierungen zeichnen sich warmfeste ferritische Legierungen in der Regel durch eine bessere Wärmeleitfähigkeit und geringere Wärmeausdehnung aus, was günstig für Anwendungen in Energiewandlungsanlagen ist. Allerdings ist die Warmfestigkeit der ferritischen Werkstoffe geringer als die der austenitischen. Spezielle ferritische Eisen-Chrom-und Eisen-Aluminium-Legierungen werden durch Bildung intermetallischer Phasen gehärtet und bezüglich Warmfestigkeit, Verformbarkeit und Korrosionsbeständigkeit optimiert.

Scripta Materialia

ABSTRACT

Intermetallics

The creep behaviour of g-TiAl with L1 0 structure without second phases, g-TiAl with precipitated... more The creep behaviour of g-TiAl with L1 0 structure without second phases, g-TiAl with precipitated particles of a 2 -Ti 3 Al with D0 19 structure, and g-TiAl with the H-phase Ti 2 AlC has been studied at low stresses in the temperature range 900±1200 C. The obtained data allow the construction of creep deformation mechanism maps for the studied alloys which may be used for an extrapolation of the observed creep behaviour. At higher stresses dislocation creep occurs in all alloys, which is well described by the Dorn equation with stress exponents in the range 3±5. Extended Coble creep with threshold stress was observed only for the studied two-phase alloys. A strong temperature dependence of the threshold stress for Coble creep was found for the TiAl alloy with carbide particles. #

Acta Metallurgica, 1981

ABSTRACT

ChemInform, 1991

ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance t... more ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Acta Metallurgica, 1973

ABSTRACT

Scripta Metallurgica, 1981

MRS Proceedings, 1984

ABSTRACT The deformation behaviour of the ordered intermetallic (Fe,Ni)Al phase with B2 structure... more ABSTRACT The deformation behaviour of the ordered intermetallic (Fe,Ni)Al phase with B2 structure is studied as a function of composition and temperature with stress strain tests and creep tests. The alloy composition has been varied with respect to stoichiometry and the Fe/Ni ratio. The creep resistivity depends on the alloy composition in a complex manner: a deviation from the stoichiometric compositions leads to a reduction of the creep resistance, and there is a maximum of the creep resistance for the ternary alloys with about 10% Fe.

Materials Science and Engineering, 1986

The creep behaviour of the ordered intermetallic (Fe, Ni)Al phase with a B2 structure was studied... more The creep behaviour of the ordered intermetallic (Fe, Ni)Al phase with a B2 structure was studied as a function of stress (for strain rates between 10 -9 and 10 -5 s-l), temperature (650-11 O0 °C) and composition. The secondary creep behaviour is described as that of disordered alloys by the Dorn equation. A low energy dislocation structure is formed in the nickel-rich alloys, whereas it is not observed in the iron-rich alloys because of insufficient driving force and dislocation mobility.

Acta Metallurgica, 1969

By means of transmission electron microscopy the size distribution of Ni,Si-particles precipitate... more By means of transmission electron microscopy the size distribution of Ni,Si-particles precipitated from the solid solution of Si in Ni has been measured as a function of concentration, ageing time and temperature. In all cases the distribution and mean particle size agree with the theory of diffusioncontrolled Ostwald ripening if a variable diffusion coefficient

The creep behaviour of g-TiAl with L1 0 structure without second phases, g-TiAl with precipitated... more The creep behaviour of g-TiAl with L1 0 structure without second phases, g-TiAl with precipitated particles of a 2 -Ti 3 Al with D0 19 structure, and g-TiAl with the H-phase Ti 2 AlC has been studied at low stresses in the temperature range 900±1200 C. The obtained data allow the construction of creep deformation mechanism maps for the studied alloys which may be used for an extrapolation of the observed creep behaviour. At higher stresses dislocation creep occurs in all alloys, which is well described by the Dorn equation with stress exponents in the range 3±5. Extended Coble creep with threshold stress was observed only for the studied two-phase alloys. A strong temperature dependence of the threshold stress for Coble creep was found for the TiAl alloy with carbide particles. #

Materials Science Forum, 2005

ABSTRACT

Microscopy and Microanalysis, 2006

Materials Science and Engineering: A, 2011

The influence of hot-deformation and tempering temperature on the microstructure evolution of a 1... more The influence of hot-deformation and tempering temperature on the microstructure evolution of a 12%Cr heat resistant steel during short-term creep at 80-250 MPa and 650 • C was investigated. Quantitative determination of dislocation density and sub-grain size in the initial microstructure and after creep was investigated by STEM-HAADF. A correlation between microstructure evolution and creep response is established. All crept samples showed a significant increase of sub-grain size and a reduction of dislocation density. Hot-deformed samples showed better creep strength than non hot-deformed samples due to homogenization of the microstructure. The tempering temperature affected the dislocation density and the sub-grain size evolution, influencing the creep behavior.

Gegenüber warmfesten austenitischen Metalllegierungen zeichnen sich warmfeste ferritische Legieru... more Gegenüber warmfesten austenitischen Metalllegierungen zeichnen sich warmfeste ferritische Legierungen in der Regel durch eine bessere Wärmeleitfähigkeit und geringere Wärmeausdehnung aus, was günstig für Anwendungen in Energiewandlungsanlagen ist. Allerdings ist die Warmfestigkeit der ferritischen Werkstoffe geringer als die der austenitischen. Spezielle ferritische Eisen-Chrom-und Eisen-Aluminium-Legierungen werden durch Bildung intermetallischer Phasen gehärtet und bezüglich Warmfestigkeit, Verformbarkeit und Korrosionsbeständigkeit optimiert.

Scripta Materialia

ABSTRACT

Intermetallics

The creep behaviour of g-TiAl with L1 0 structure without second phases, g-TiAl with precipitated... more The creep behaviour of g-TiAl with L1 0 structure without second phases, g-TiAl with precipitated particles of a 2 -Ti 3 Al with D0 19 structure, and g-TiAl with the H-phase Ti 2 AlC has been studied at low stresses in the temperature range 900±1200 C. The obtained data allow the construction of creep deformation mechanism maps for the studied alloys which may be used for an extrapolation of the observed creep behaviour. At higher stresses dislocation creep occurs in all alloys, which is well described by the Dorn equation with stress exponents in the range 3±5. Extended Coble creep with threshold stress was observed only for the studied two-phase alloys. A strong temperature dependence of the threshold stress for Coble creep was found for the TiAl alloy with carbide particles. #

Acta Metallurgica, 1981

ABSTRACT

ChemInform, 1991

ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance t... more ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Acta Metallurgica, 1973

ABSTRACT

Scripta Metallurgica, 1981

MRS Proceedings, 1984

ABSTRACT The deformation behaviour of the ordered intermetallic (Fe,Ni)Al phase with B2 structure... more ABSTRACT The deformation behaviour of the ordered intermetallic (Fe,Ni)Al phase with B2 structure is studied as a function of composition and temperature with stress strain tests and creep tests. The alloy composition has been varied with respect to stoichiometry and the Fe/Ni ratio. The creep resistivity depends on the alloy composition in a complex manner: a deviation from the stoichiometric compositions leads to a reduction of the creep resistance, and there is a maximum of the creep resistance for the ternary alloys with about 10% Fe.

Materials Science and Engineering, 1986

The creep behaviour of the ordered intermetallic (Fe, Ni)Al phase with a B2 structure was studied... more The creep behaviour of the ordered intermetallic (Fe, Ni)Al phase with a B2 structure was studied as a function of stress (for strain rates between 10 -9 and 10 -5 s-l), temperature (650-11 O0 °C) and composition. The secondary creep behaviour is described as that of disordered alloys by the Dorn equation. A low energy dislocation structure is formed in the nickel-rich alloys, whereas it is not observed in the iron-rich alloys because of insufficient driving force and dislocation mobility.

Acta Metallurgica, 1969

By means of transmission electron microscopy the size distribution of Ni,Si-particles precipitate... more By means of transmission electron microscopy the size distribution of Ni,Si-particles precipitated from the solid solution of Si in Ni has been measured as a function of concentration, ageing time and temperature. In all cases the distribution and mean particle size agree with the theory of diffusioncontrolled Ostwald ripening if a variable diffusion coefficient

The creep behaviour of g-TiAl with L1 0 structure without second phases, g-TiAl with precipitated... more The creep behaviour of g-TiAl with L1 0 structure without second phases, g-TiAl with precipitated particles of a 2 -Ti 3 Al with D0 19 structure, and g-TiAl with the H-phase Ti 2 AlC has been studied at low stresses in the temperature range 900±1200 C. The obtained data allow the construction of creep deformation mechanism maps for the studied alloys which may be used for an extrapolation of the observed creep behaviour. At higher stresses dislocation creep occurs in all alloys, which is well described by the Dorn equation with stress exponents in the range 3±5. Extended Coble creep with threshold stress was observed only for the studied two-phase alloys. A strong temperature dependence of the threshold stress for Coble creep was found for the TiAl alloy with carbide particles. #

Materials Science Forum, 2005

ABSTRACT

Microscopy and Microanalysis, 2006