Microstructural effects on distortion and solid-liquid segregation during liquid phase sintering under microgravity conditions

Journal Article · Sat Aug 01 04:00:00 EDT 1998 · Metallurgical and Materials Transactions B: Process Metallurgy and Materials Processing Science

DOI:https://doi.org/10.1007/s11663-998-0145-4· OSTI ID:651078

Johnson, J L; Upadhyaya, A; German, R M ^[1]

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1. Pennsylvania State Univ., University Park, PA (United States). Dept. of Engineering Science and Mechanics

Tungsten heavy alloys with compositions ranging from 78 to 98 wt pct tungsten were liquid phase sintered at 1507 C under microgravity conditions for 120 minutes. The sintered microstructures were quantitatively measured for solid volume fraction, grain size, connectivity, and contiguity. Links between these microstructural parameters were analyzed and compared to previously derived empirical equations. The macrostructures of the samples were also quantified and correlated to the underlying microstructures. Critical values of solid volume fraction, contiguity, and connectivity required for free-standing structural rigidity were defined for various degrees of bond rigidity as represented by the dihedral angle. The results are used to predict the degree of solid-liquid segregation due to density differences between the solid and the liquid.

• Sponsoring Organization: USDOE
• OSTI ID: 651078
• Journal Information: Metallurgical and Materials Transactions B: Process Metallurgy and Materials Processing Science, Journal Name: Metallurgical and Materials Transactions B: Process Metallurgy and Materials Processing Science Journal Issue: 4 Vol. 29; ISSN MTBSEO
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CHEMICAL COMPOSITION
CORRELATIONS
LIQUID METALS
MICROSTRUCTURE
SEGREGATION
SINTERING
SOLIDS
TEMPERATURE RANGE 1000-4000 K
TUNGSTEN BASE ALLOYS