Brazed joint properties and microstructure of SCS-6/{beta}21S titanium matrix composites

Journal Article · Wed Nov 01 04:00:00 EST 1995 · Welding Journal

OSTI ID:131642

Hoffman, E K; Bird, R K; Dicus, D L ^[1]

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1. National Aeronautics and Space Administration, Hampton, VA (United States). Langley Research Center

The properties and microstructure of brazed joints of SCS-6 SiC fiber reinforced {beta}21S (Ti-15Mo-2.7Nb-3Al-0.2Si, wt-%) titanium matrix composite (TMC) were investigated. Brazed joint specimens were fabricated from TMC using two different forms of commercially available Ti-15Cu-15Ni braze filler metal. The brazed joint specimens were tested in air at room temperature and 1,500 F (815 C) using overlap tensile shear (OLTS) tests. Metallurgical and fractographic analyses were used to characterize the microstructure, brazing filler metal/TMC interactions, and joint failure modes. The fractographic results indicated that TMC delamination is a dominant failure mode for this type of joint. At room temperature, the TMC brazed joint specimens failed by TMC delamination and TMC tensile failure, with the brazed joint remaining intact. Therefore, the performance of the brazed joint specimens at room temperature is limited by the interlaminar strength of the TMC and not by the braze strength. At 1,500 F, the TMC brazed joint specimens exhibited a combination of delamination and braze shear failure. Thus, the high-temperature performance of the brazed joint specimens may be limited by both the TMC interlaminar properties and the strength of the braze.

• OSTI ID: 131642
• Journal Information: Welding Journal, Journal Name: Welding Journal Journal Issue: 11 Vol. 74; ISSN 0043-2296; ISSN WEJUA3
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ALLOYS
BRAZED JOINTS
COMPOSITE MATERIALS
FAILURES
MECHANICAL PROPERTIES
MECHANICAL TESTS
MICROSTRUCTURE
MOLYBDENUM ALLOYS
NIOBIUM ALLOYS
SILICON ADDITIONS
SILICON CARBIDES
TITANIUM BASE ALLOYS