Ti-modified niobium-silicide based directionally solidified in-situ composites
- General Electric Co., Schenectady, NY (United States). Corporate Research and Development Center
- Wright State Univ., Dayton, OH (United States). Dept. of Mechanical and Materials Engineering
This paper examines microstructure-property relationships in high-temperature directionally solidified (DS) in-situ composites based on Nb silicides, such as Nb{sub 3}Si and Nb{sub 5}Si{sub 3}. These in-situ composites are based on the Nb{sub 3}Si-Nb binary eutectic, and are alloyed with Ti. They were prepared using cold crucible Czochralski crystal growth. Ternary Nb-Ti-Si alloys with Ti concentrations from 9 to 45%, and Si concentrations from 10 to 25%, were directionally solidified to generate aligned two- and three-phase composites containing a Nb solid solution with Nb{sub 3}Si and Nb{sub 5}Si{sub 3} silicides. Fracture toughness values generally greater than 10 MPa{radical}m were measured in these composites. For a given Si concentration, the fracture toughness of the Ti-containing composites was increased {approximately}6 MPa{radical}m over that of the binary alloy composites. The effects of Si concentration, and a range of Nb:Ti ratios, on microstructure, phase equilibria, and fracture toughness were examined.
- OSTI ID:
- 571911
- Report Number(s):
- CONF-961202--
- Country of Publication:
- United States
- Language:
- English
Similar Records
Microstructure, creep and fracture toughness of directionally solidified NiAl/(Cr,Mo) alloys modified with Hf, Si, Ta, Ti additions
The effects of in-situ processing methods on the microstructure and fracture toughness of V-V{sub 3}Si composites