Atomic structures and compositions of internal interfaces. [Produced by internal oxidation of alloys]

Technical Report · Mon May 10 04:00:00 EDT 1993

DOI:https://doi.org/10.2172/6787567· OSTI ID:6787567

Seidman, D N ^[1]; Merkle, K L ^[2]

---

1. Northwestern Univ., Evanston, IL (United States). Dept. of Materials Science and Engineering
2. Argonne National Lab., IL (United States). Materials Science Div.

This research program addresses fundamental questions concerning the relations between atomic structures and compositions of homophase and heterophase interfaces. Metal/ceramic heterophase interfaces are created via the process of internal oxidation of metallic alloys. The interfaces are studied via a combination of conventional transmission electron microscopy, high resolution electron microscopy, field-ion microscopy and atom probe microscopy. The latter technique is employed to chemically sequence the interfacial region, and to show that the terminating (222) plane of MgO and CdO consists solely of oxygen atoms forthe Cu/MgO (111) and Ag/CdO (111) heterophase interfaces, respectively; this is achieved with no deconvolution of the experimental data. The evolution of metal/ceramic heterophase interfaces is studied by following the process of internal oxidation on an atomic scale from its very earliest stages. It is demonstrated that during the early stages of internal oxidation that metal atom clusters as well as hypo and hyperstoichiometric metal-oxygen clusters are present. Solute-atom segregation to grain boundaries is studied in binary metal alloys employing the free energy simulations and the overlapping distribution Monte Carlo methodologies for dilute Pt(Au), Cu(Ni) and Pd(Ni) alloys for both twist and tilt boundaries.

• Research Organization: Northwestern Univ., Evanston, IL (United States). Dept. of Materials Science and Engineering; Argonne National Lab., IL (United States)
• Sponsoring Organization: DOE; USDOE, Washington, DC (United States)
• DOE Contract Number: FG02-89ER45403
• OSTI ID: 6787567
• Report Number(s): DOE/ER/45403-4; ON: DE93014840
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102 -- Metals & Alloys-- Structure & Phase Studies
360105* -- Metals & Alloys-- Corrosion & Erosion
ALKALINE EARTH METAL COMPOUNDS
ALLOYS
CADMIUM COMPOUNDS
CADMIUM OXIDES
CHALCOGENIDES
CHEMICAL REACTIONS
COPPER ALLOYS
DOCUMENT TYPES
ELECTRON MICROSCOPY
ELEMENTS
INTERFACES
ION MICROSCOPY
MAGNESIUM ADDITIONS
MAGNESIUM ALLOYS
MAGNESIUM COMPOUNDS
MAGNESIUM OXIDES
METALS
MICROSCOPY
OXIDATION
OXIDES
OXYGEN COMPOUNDS
PROGRESS REPORT
SILVER
TRANSITION ELEMENTS