Point defect behavior in the B2 type intermetallic compounds CoAl

Journal Article · Tue Oct 01 04:00:00 EDT 1996 · Scripta Materialia

DOI:https://doi.org/10.1016/1359-6462(96)00204-7· OSTI ID:382486

Kogachi, M; Tanahashi, T ^[1]

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1. Osaka Prefecture Univ., Sakai (Japan)

The B2 type intermetallic compounds consisting of VIII and IIIb component atoms, such as the NiAl and CoAl, exhibit different types of point defects with deviation of alloy composition from the stoichiometry. Thus the determination of detailed defect structure is a very important subject for more clarification of its correlation to various properties in these compounds. Some work focusing on this problem has been recently presented by means of the powder X-ray diffraction (XRD) for the compounds NiAl, CoAl, and FeAl. The results for the former two compounds revealed that other than substantial amounts of Ni(Co) vacancies and antistructure defects (ASD), appreciable amounts of the Al-vacancy and Al-ASD which are neglected in the triple defect model (TRD model) were formed in the Al-rich composition region. It is an interesting problem to compare the defect behavior in NiAl with that in other compounds belonging to the same group: e.g., CoAl and FeAl. The aim of the present paper is thus to determine the defect structure appearing in the B2 type intermetallic compounds CoAl as a function of composition from the XRD and density measurements.

• OSTI ID: 382486
• Journal Information: Scripta Materialia, Journal Name: Scripta Materialia Journal Issue: 7 Vol. 35; ISSN XZ503X
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ALLOYS
BULK DENSITY
CHEMICAL COMPOSITION
COBALT ALLOYS
CORRELATIONS
INTERMETALLIC COMPOUNDS
MECHANICAL PROPERTIES
PHYSICAL PROPERTIES
POINT DEFECTS
STOICHIOMETRY
VACANCIES
VOIDS
X-RAY DIFFRACTION