Effects of microstructures, alloying additions, and processing routes on the room- and elevated-temperature fracture toughnesses of gamma-base titanium aluminides were investi-gated. Microstructure was found to have a strong influence on the fracture toughness both at room and elevated temperatures. Lamellar microstructure materials exhibited high fracture toughness compared with duplex microstructure materials, which in turn possessed high fracture toughness compared with the equiaxed microstructure materials. Alloying additions affected the fracture toughness at elevated temperatures significantly. The addition of chromium improved the low-temperature fracture toughness (below 800 °), while the addition of niobium increased the fracture toughness above 800 °. Grain size refining, as a result of isothermal forging after casting and heat treatment, had less influence on the fracture toughness.
|Number of pages||9|
|Journal||Metallurgical and Materials Transactions A|
|Publication status||Published - 1995 Feb|
ASJC Scopus subject areas
- Condensed Matter Physics
- Mechanics of Materials
- Metals and Alloys