Transmission electron microscopy studying of structural features of NiTi B2 phase formed under pulsed electron-beam impact
- Institute of Strength Physicists and Materials Science SB RAS, Tomsk, 634055 (Russian Federation)
- National Research Tomsk State University, Tomsk, 634050 (Russian Federation)
By transmission electron microscopy method the evolution of structural-phase states on a depth of close to equiatomic NiTi modified layer has been studied. Modification performed by pulse impact on its surface low-energy high-current electron beam (beam energy density 10 J/sm{sup 2}, 10 pulses, pulse duration 50mks). It is established that during the treatment in the layer thickness of 8–10 μm, the melting of primary B2 phase and contained therein as Ti2Ni phase particles occurs. The result is change in the concentration ratio of titanium and nickel in the direction of increasing titanium content, which was confirmed by X-ray analysis in the form of increased unit cell parameter B2 phase. Analysis of the electron diffraction pattern showed that the modified layer is characterized as a highly distorted structure on the basis of bcc lattice. Lattice distortions are maximal near the surface and extends to a depth of melt. In subjacent layer there is gradual decline lattice distortions is observed.
- OSTI ID:
- 22492569
- Journal Information:
- AIP Conference Proceedings, Vol. 1683, Issue 1; Conference: International conference on advanced materials with hierarchical structure for new technologies and reliable structures 2015, Tomsk (Russian Federation), 21-25 Sep 2015; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
- Country of Publication:
- United States
- Language:
- English
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