The interface in tungsten fiber reinforced niobium metal-matrix composites

Technical Report · Fri Sep 01 00:00:00 EDT 1989

DOI:https://doi.org/10.2172/5827839· OSTI ID:5827839

The creep resistance of tungsten fiber reinforced niobium metal- matrix composites was evaluated. The interface region between the fiber and matrix was characterized by microhardness and electron probe microanalysis measurements which indicated that its properties were between those of fiber and matrix. However, the measured properties of the composite exceeded those calculated by the rule of mixtures even when the interface zone was assumed to retain all the strength of the fiber. The composite structure appeared to enhance the strengths of both the fibers and the matrix above what they exhibited in stand-alone tests. The effect of fiber orientation and matrix alloy composition on the fiber/matrix interface were also evaluated. Small alloying additions of zirconium and tungsten to the niobium matrix affected the creep resistance of the composites only slightly. A decrease in the creep resistance of the composite with increasing zirconium content in the matrix was ascribed to an increase in the diffusion rate of the fiber/matrix interdiffusion reaction, and a slight increase in the creep resistance of the composite was observed with an addition of 9 w % tungsten to the matrix. In addition, Kirkendall void formation was observed a the fiber/matrix interface; the void distribution differed depending on the fiber orientation relative to the stress axis. 36 refs., 26 figs., 6 tabs.

• Research Organization: NASA Lewis Research Center, Cleveland, OH (United States)
• DOE Contract Number: AI03-86SF16310
• OSTI ID: 5827839
• Report Number(s): DOE/NASA/16310-10; NASA-TM-102122; ON: DE89017744
• Resource Relation: Other Information: Thesis (Ph.D.). Portions of this document are illegible in microfiche products
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COMPOSITE MATERIALS
INTERFACES
NIOBIUM BASE ALLOYS
MECHANICAL PROPERTIES
TUNGSTEN
ZIRCONIUM ALLOYS
CREEP
DIFFUSION
ELECTRON PROBES
FAILURES
FIBERS
REGRESSION ANALYSIS
RUPTURES
TENSILE PROPERTIES
VOIDS
ALLOYS
ELEMENTS
MATERIALS
MATHEMATICS
METALS
NIOBIUM ALLOYS
PROBES
STATISTICS
TRANSITION ELEMENTS
360603* - Materials- Properties
360602 - Other Materials- Structure & Phase Studies