A critical review of the physical and mechanical properties of NiAl is presented. The physical properties examined include electronic structure and bonding, crystal structure and phase stability, thermodynamic properties, elastic properties, and electrical, magnetic, and thermal properties. Discussion of crystal defects in NiAl include both constitutional and thermal point defects, the core structure and energy of line defects, and planar defects (shear faults, grain boundaries, and free surfaces). The mechanical properties, substructure, and mechanisms of ductility of NiAl single crystals and polycrystals are reviewed in detail, while alloying effects and the deformation of NiAl martensite are briefly described. The fracture toughness, modes of fracture, and cyclic properties reported in the literature are assessed. A critical analysis of diffusion data for NiAl is followed by a discussion of the activation energy and mechanisms of diffusion. This information is related to the creep properties of NiAl, and additional critical comments concerning the substructure and creep mechanisms of NiAl are provided. A review of the environmental resistance of NiAl is followed by a brief discussion of several current and potential applications of NiAl. Concluding remarks include suggestions for future research on NiAl.

Overview No. 104 The physical and mechanical properties of NiAl

Considerable work has been performed on NiAl over the last three decades, with an extremely rapid growth in research on this intermetallic occurring in the last few years due to recent interest in this material for electronic and high temperature structural applications. However, many physical properties and the controlling fracture and deformation mechanisms over certain temperature regimes are still in question. Part of this problem lies in the incomplete characterization of many of the alloys previously investigated. Fragmentary data on processing conditions, chemistry, microstructure and the apparent difficulty in accurately measuring composition has made direct comparison between individual studies sometimes tenuous. Therefore, the purpose of this review is to summarize all available mechanical and pertinent physical properties on NiAl, stressing the most recent investigations, in an attempt to understand the behavior of NiAl and its alloys over a broad temperature range.

Physical and mechanical properties of the B2 compound NiAl

Structure and chemical bonding in zintl-phases containing lithium

Survey on tables and figures containing data on alloys and compounds between 3d-elements and Cu, Ag and Au, respectively.

Alloys and compounds of 3d elements with main group elements

Stable and epitaxial metal/III-V semiconductor heterostructures

Defect structure of β-LiAl

Li7 self diffusion in LiAl—An NMR study

Electronic structure of β′-NiAl

Measurements of the AC susceptibility and Faraday balance susceptibility performed on CoxGa1-x slow-cooled samples are reported for compositions 0.48<or=x<or=0.58. Measurements were performed in the temperature range 0.5K<T<400K and for magnetic fields of below about 1 mT and 0.75T. Spin-glass behaviour is identified for the composition range 0.50<or=x<0.56. The transition region between spin glass and ferromagnetism was investigated near x=0.56. This corresponds to a critical concentration of antistructure defects of about 7.0%.

https://iopscience.iop.org/article/10.1088/0305-4608/12/2/010/pdf

J.O. Brittain

Papers

Defect structure of β-LiAl

Li7 self diffusion in LiAl—An NMR study

Electronic structure of β′-NiAl

Magnetic properties of CoGa alloys and the transition from spin glass to ferromagnetism

Li self-diffusion in pure and doped β-LiAl using pulsed-field gradient NMR