Developing grain boundary diagrams as a materials science tool: A case study of nickel-doped molybdenum

Journal Article · Fri Jul 01 04:00:00 EDT 2011 · Physical Review. B, Condensed Matter and Materials Physics

DOI:https://doi.org/10.1103/PHYSREVB.84.014105· OSTI ID:21596814

Xiaomeng, Shi; Jian, Luo ^[1]

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1. School of Materials Science and Engineering, Center for Optical Materials Science and Engineering Technologies, Clemson University, Clemson, South Carolina 29634 (United States)

Impurity-based, premelting-like, grain boundary (GB) ''phases'' (complexions) can form in alloys and influence sintering, creep, and microstructural development. Calculation of Phase Diagrams (CalPhaD) methods and Miedema-type statistical interfacial thermodynamic models are combined to forecast the formation and stability of subsolidus quasiliquid GB phases in binary alloys. This work supports a long-range scientific goal of developing ''GB (phase) diagrams'' as a new materials science tool to help controlling the materials fabrication processing and resultant materials properties. Using nickel-doped molybdenum as a model system, a type of GB diagram (called ''{lambda} diagram'') is computed to represent the temperature- and composition-dependent thermodynamic tendency for general GBs to disorder. Subsequently, controlled sintering experiments are conducted to estimate the GB diffusivity as a function of temperature and overall composition, and the experimental results correlate well with the computed GB diagram. Although they are not yet rigorous GB-phase diagrams with well-defined transition lines, the predictability and usefulness of such {lambda} diagrams are demonstrated. Related interfacial thermodynamic models and computational approaches are discussed.

• OSTI ID: 21596814
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Journal Name: Physical Review. B, Condensed Matter and Materials Physics Journal Issue: 1 Vol. 84; ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALLOY SYSTEMS
ALLOYS
BINARY ALLOY SYSTEMS
DIAGRAMS
DOPED MATERIALS
ELEMENTS
FABRICATION
GRAIN BOUNDARIES
IMPURITIES
INFORMATION
MATERIALS
MATHEMATICAL MODELS
METALS
MICROSTRUCTURE
MOLYBDENUM
NICKEL ADDITIONS
NICKEL ALLOYS
PARTICLE MODELS
PHASE DIAGRAMS
REFRACTORY METALS
SINTERING
STABILITY
STATISTICAL MODELS
TEMPERATURE DEPENDENCE
THERMODYNAMIC MODEL
TRANSITION ELEMENT ALLOYS
TRANSITION ELEMENTS