Ta and Nb reinforced MoSi sub 2

Conference · Wed Apr 11 04:00:00 EDT 1990

OSTI ID:6963448

Carter, D H ^[1]; Martin, P L ^[2]

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1. Los Alamos National Lab., NM (USA)
2. Rockwell International Corp., Thousand Oaks, CA (USA). Science Center

MoSi{sub 2} matrix composites have been recognized lately as potential materials for structural applications at elevated temperatures. Specifically, MoSi{sub 2} composites may exhibit useful properties at temperatures to 1400{degrees}C. Previous work improved the yield strength of MoSi{sub 2} at 1400{degrees}C by a factor of five through SiC whisker reinforcement. Current research is directed towards increasing the fracture toughness of MoSi{sub 2} through the addition of ductile phase reinforcements such as niobium and tantalum. The reaction between Nb and MoSi{sub 2} to form (Mo,Nb){sub 5}Si{sub 3} proceeds with faster kinetics at hot isostatic press temperatures as low as 1100{degrees}C when compared to the reaction between Ta and MoSi{sub 2} to form (Mo,Ta){sub 5}Si{sub 3}. This reaction product exhibits very poor properties, as evidenced by crack propagation through this layer during fracture. The feasibility of hot working these composites to produce tailored microstructures is examined. 11 refs., 10 figs.

• Research Organization: Los Alamos National Lab., NM (USA)
• Sponsoring Organization: DOE/DP
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 6963448
• Report Number(s): LA-UR-90-1310; CONF-900466--24; ON: DE90010596
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360602 -- Other Materials-- Structure & Phase Studies
360603* -- Materials-- Properties
ALLOYS
CARBIDES
CARBON COMPOUNDS
COMPOSITE MATERIALS
CREEP
CRYSTAL STRUCTURE
ELEMENTS
FABRICATION
HOT WORKING
INTERMETALLIC COMPOUNDS
MATERIALS
MATERIALS WORKING
MECHANICAL PROPERTIES
METALS
MICROSTRUCTURE
MOLYBDENUM COMPOUNDS
MOLYBDENUM SILICIDES
NIOBIUM
REFRACTORY METAL COMPOUNDS
REINFORCED MATERIALS
SILICIDES
SILICON CARBIDES
SILICON COMPOUNDS
TANTALUM
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS