Development of high toughness, high strength aluminide-bonded carbide ceramics
- Oak Ridge National Lab., TN (United States); and others
Cemented carbides are widely used in applications where resistance to abrasion and wear are important, particularly in combination with high strength and stiffness. In the present case, ductile aluminides have been used as a binder phase to fabricate dense carbide cermets by either sintering of mixed powders or a melt-infiltration sintering process. The choice of an aluminide binder was based on the exceptional high temperature strength and chemical stability exhibited by these alloys. For example, TiC-based composites with a Ni{sub 3}Al binder phase exhibit improved oxidation resistance, Young`s moduli > 375 GPa, high fracture strengths (> 1 GPa) that are retained to {ge} 900{degrees}C, and fracture toughness values of 10 to 15 MPa{radical}m, identical to that measured in commercial cobalt-bonded WC with the same test method. The thermal diffusivity values at 200{degrees}C for these composites are {approximately} 0.070 to 0.075 cm{sup 2}/s while the thermal expansion coefficients rise with Ni3Al content from {approximately} 8 to {approximately}11 x 10{sup {minus}6}/{degrees}C over the range of 8 to 40 vol. % Ni{sub 3}Al. The oxidation and acidic corrosion resistances are quite promising as well. Finally, these materials also exhibit good electrical conductivity allowing them to be sectioned and shaped by electrical discharge machining (EDM) processes.
- Research Organization:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- OSTI ID:
- 494116
- Report Number(s):
- ORNL/TM-13399; ON: DE97005392; TRN: 97:003310-0012
- Resource Relation:
- Other Information: PBD: Apr 1997; Related Information: Is Part Of Advanced Industrial Materials (AIM) program. Annual progress report. FY 1996; PB: 292 p.
- Country of Publication:
- United States
- Language:
- English
Similar Records
FeAl-TiC and FeAl-WC composites - melt infiltration processing, microstructure and mechanical properties
Processing and properties of FeAl-bonded composites