On the improvement of the ductility of molybdenum by spinel (MgAl2O4) particles
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J. H. Schneibel
,
M. P. Brady
Abstract
In a 1967 patent, D. M. Scruggs found that the room temperature ductility of molybdenum is improved by adding several volume percent of MgAl2O4 spinel particles. The present work substantiates Scruggs’ claim – with increasing MgAl2O4 volume fraction the ductility of Mo– MgAl2O4 is found to pass through a maximum near 2.5 vol%. Scruggs postulated that gettering of detrimental impurities was responsible for this effect. In the present work, fracture initiated at microcracks that formed on the Mo– MgAl2O4 specimen surfaces during tensile testing. The ductility maximum is interpreted in terms of the change in the microcrack size (which is assumed to scale with the grain size) and the ultimate tensile stress, as the MgAl2O4 volume fraction increases. Fracture occurs once a critical local stress-intensity factor, which is approximately independent of the MgAl2O4 volume fraction, is reached.
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The authors acknowledge scanning Auger microscopy by H. M. Meyers III. This work was sponsored by the Office of Fossil Energy, Advanced Research Materials (ARM) Program, U.S. Department of Energy, under contract no. DE-AC05-00OR22725 with Oak Ridge National Laboratory managed by UT-Battelle, LLC (for JHS and MPB), and under contract no. DE-AC03-76SF0098 with the Lawrence Berkeley National Laboratory (for ROR).
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© 2005 Carl Hanser Verlag, München
Articles in the same Issue
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- Editorial
- Editorial
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- A unified microstructural metal plasticity model applied in testing, processing, and forming of aluminium alloys
- Implications of non-negligible microstructural variations during steady-state deformation
- Tertiary creep of metals and alloys
- Interactions between particles and low-angle dislocation boundaries during high-temperature deformation
- Strain-rate sensitivity of ultrafine-grained materials
- Transient plastic flow at nominally fixed structure due to load redistribution
- Vacancy concentrations determined from the diffuse background scattering of X-rays in plastically deformed copper
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- About stress reduction experiments during constant strain-rate deformation tests
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- Variational approach to subgrain formation
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- Creep properties at 125 °C of an AM50 Mg alloy modified by Si additions
- Dependence of mechanical strength on grain structure in the γ′ and oxide dispersions-trengthened nickelbase superalloy PM 3030
- On the improvement of the ductility of molybdenum by spinel (MgAl2O4) particles
- Hot workability and extrusion modelling of magnesium alloys
- Characterization of hot-deformation behaviour of Zircaloy-2: a comparison between kinetic analysis and processing maps
- Requirements for microstructural investigations of steels used in modern power plants
- Influence of Lüders band formation on the cyclic creep behaviour of a low-carbon steel for piping applications
- Creep and creep rupture behaviour of 650 °C ferritic/martensitic super heat resistant steels
- Toughening mechanisms of a Ti-based nanostructured composite containing ductile dendrites
- Notifications/Mitteilungen
- Personal/Personelles
- News/Aktuelles
- Conferences/Konferenzen
Articles in the same Issue
- Frontmatter
- Editorial
- Editorial
- Articles Basic
- Identifying creep mechanisms in plastic flow
- A unified microstructural metal plasticity model applied in testing, processing, and forming of aluminium alloys
- Implications of non-negligible microstructural variations during steady-state deformation
- Tertiary creep of metals and alloys
- Interactions between particles and low-angle dislocation boundaries during high-temperature deformation
- Strain-rate sensitivity of ultrafine-grained materials
- Transient plastic flow at nominally fixed structure due to load redistribution
- Vacancy concentrations determined from the diffuse background scattering of X-rays in plastically deformed copper
- Effect of heating rate in α + γ dual-phase field on lamellar microstructure and creep resistance of a TiAl alloy
- About stress reduction experiments during constant strain-rate deformation tests
- Finite-element modelling of anisotropic single-crystal superalloy creep deformation based on dislocation densities of individual slip systems
- Variational approach to subgrain formation
- Articles Applied
- Pseudoelastic cycling of ultra-fine-grained NiTi shape-memory wires
- Creep properties at 125 °C of an AM50 Mg alloy modified by Si additions
- Dependence of mechanical strength on grain structure in the γ′ and oxide dispersions-trengthened nickelbase superalloy PM 3030
- On the improvement of the ductility of molybdenum by spinel (MgAl2O4) particles
- Hot workability and extrusion modelling of magnesium alloys
- Characterization of hot-deformation behaviour of Zircaloy-2: a comparison between kinetic analysis and processing maps
- Requirements for microstructural investigations of steels used in modern power plants
- Influence of Lüders band formation on the cyclic creep behaviour of a low-carbon steel for piping applications
- Creep and creep rupture behaviour of 650 °C ferritic/martensitic super heat resistant steels
- Toughening mechanisms of a Ti-based nanostructured composite containing ductile dendrites
- Notifications/Mitteilungen
- Personal/Personelles
- News/Aktuelles
- Conferences/Konferenzen
