The effect of impurity content on thermally activated deformation in NiAl single crystals

Journal Article · Mon Aug 15 00:00:00 EDT 1994 · Scripta Metallurgica et Materialia; (United States)

DOI:https://doi.org/10.1016/0956-716X(94)90007-8· OSTI ID:6983339

Kitano, K; Pollock, T M ^[1]; Noebe, R D ^[2]

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1. Carnegie Mellon Univ., Pittsburgh, PA (United States). Dept. of Materials Science and Engineering
2. National Aeronautics Space Agency, Cleveland, OH (United States). Lewis Research Center

NiAl-base materials are attractive candidates for high temperature structural applications due to their low density, excellent oxidation resistance and high thermal conductivity. However, in single crystal and polycrystalline form, NiAl suffers from low tensile ductility and toughness. The mechanisms responsible for the limited ductility of NiAl single crystals are still in question. For this reason, thermally activated deformation in NiAl single crystals has been studied with the use of strain-rate change experiments. The preliminary results suggest that the intrinsic mobility of a <111>, and to a lesser extent a <100> dislocations, is limited below the DBTT in NiAl. To examine the influence of interstitial impurities and the possibility that strain-aging embrittlement is the mechanism responsible for the limited ductility of NiAl, further experiments on high purity NiAl crystals have been conducted for comparison to the results on commercial purity crystals.

• OSTI ID: 6983339
• Journal Information: Scripta Metallurgica et Materialia; (United States), Journal Name: Scripta Metallurgica et Materialia; (United States) Vol. 31:4; ISSN 0956-716X; ISSN SCRMEX
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360103* -- Metals &amp; Alloys-- Mechanical Properties
ALLOYS
ALUMINIUM ALLOYS
COMPARATIVE EVALUATIONS
CRYSTALS
DATA
DEFORMATION
DUCTILE-BRITTLE TRANSITIONS
DUCTILITY
EVALUATION
EXPERIMENTAL DATA
HEAT RESISTANT MATERIALS
HEAT RESISTING ALLOYS
INFORMATION
INTERMETALLIC COMPOUNDS
MATERIALS
MECHANICAL PROPERTIES
MONOCRYSTALS
NICKEL ALLOYS
NUMERICAL DATA
TENSILE PROPERTIES