Tensile properties and strain rate sensitivity of Ti-47Al-2Cr-0.2Si sheet material with different microstructures

Journal Article · Thu Aug 01 04:00:00 EDT 1996 · Scripta Materialia

DOI:https://doi.org/10.1016/1359-6462(96)00143-1· OSTI ID:271592

Clemens, H ^[1]; Glatz, W ^[2]; Appel, F ^[3]

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1. Plansee AG, Reutte (Austria)
2. Montanuniversitaet, Leoben (Austria). Inst. fuer Metallkunde und Werkstoffpruefung
3. GKSS Research Centre, Geesthacht (Germany). Inst. for Materials Research

New materials based on gamma titanium aluminides (gamma alloys) have emerged as potential candidates for high temperature applications such as aerospace structural components (e.g., airframes, turbine components, thermal protection systems) and automotive parts (e.g., exhaust valves, turbocharger rotors). Because of their low density, high Young`s modulus, high-temperature strength retention, good oxidation and burn resistance, the so-called second generation gamma alloys are able to exceed the application temperature of advanced titanium alloys and also to replace nickel- and iron-based superalloys up to 800C. However, poor formability and low room temperature (RT) ductility resulting in low fracture toughness have limited possible applications. The present paper deals with the dependence of tensile properties of Ti-47Al-2Cr-0.2Si (composition in atomic-%) sheet material on microstructure and test conditions. Four different microstructures, i.e., fine-grained primary annealed (PA), near gamma (NG), duplex (DU) as well as coarse-grained fully lamellar (FL) have been investigated with emphasis on the influence of grain size, phase distribution, and strain rate on tensile properties at 700 C. Fractography was conducted by scanning electron microscopy (SEM) to examine the influence of temperature on the fracture behavior and to determine the onset of dynamic recrystallization effects.

• OSTI ID: 271592
• Journal Information: Scripta Materialia, Journal Name: Scripta Materialia Journal Issue: 3 Vol. 35; ISSN 1359-6462; ISSN XZ503X
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
36 MATERIALS SCIENCE
AEROSPACE INDUSTRY
ALUMINIUM ALLOYS
AUTOMOBILES
CHEMICAL COMPOSITION
CHROMIUM ALLOYS
FRACTOGRAPHY
FRACTURE PROPERTIES
GRAIN SIZE
INTERMETALLIC COMPOUNDS
LAMELLAE
MATERIALS
MICROSTRUCTURE
RECRYSTALLIZATION
SCANNING ELECTRON MICROSCOPY
SILICON ADDITIONS
STRAIN RATE
TEMPERATURE DEPENDENCE
TENSILE PROPERTIES
TITANIUM ALLOYS