Toughening MoSi{sub 2} with Niobium metal -- Effects of size and orientation of ductile laminae

Journal Article · Sat Jan 01 04:00:00 EST 1994 · Acta Metallurgica et Materialia

DOI:https://doi.org/10.1016/0956-7151(94)90064-7· OSTI ID:143907

Shaw, L; Abbaschian, R ^[1]

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1. Univ. of Florida, Gainesville (United States). Dept. of Materials Science and Engineering

Effects of size and orientation of ductile laminae on the toughness of brittle matrix composites have been evaluated using MoSi{sub 2} composites reinforced with Nb laminae. Nb laminae with thicknesses ranging from 0.127 to 1.0 mm were hot pressed with MoSi{sub 2} powder to prepare the composites. Toughness of the composites was measured using four-point bend test on chevron-notched specimens. It was found that the toughness of the composites increased with increasing size of the niobium laminae. Furthermore, toughening was observed at crack propagation directions perpendicular to the laminae plane, indicating that ductile laminae offer two dimensional toughening. A model based on the bridging contribution of the ductile phase has been proposed to analyze the chevron-notched specimens of the ductile-phase-reinforced brittle matrix composites. The analysis showed that the dependence of the toughness of the composites on the size and orientation of the ductile laminae could be interpreted in terms of their bridging capability and bending contributions.

• OSTI ID: 143907
• Journal Information: Acta Metallurgica et Materialia, Journal Name: Acta Metallurgica et Materialia Journal Issue: 1 Vol. 42; ISSN 0956-7151; ISSN AMATEB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COMPOSITE MATERIALS
DUCTILITY
FRACTURE PROPERTIES
MECHANICAL PROPERTIES
MICROSTRUCTURE
MOLYBDENUM SILICIDES
NIOBIUM ALLOYS