Structural-Phase State and Microhardness of a Precursor from Equiatomic W-Ta-Mo-Nb-Zr-Cr-Ti Powder Mixture after High-Energy Mechanical Activation

The influence of mechanical activation and gamma-irradiation on the structural-phase state of Ti-Al-C powder reagents was studied. The following compositions were used for research: 1) 78% Ti + 14% Al + 8% C; 2) 80% Ti + 12% Al + 8% C; 3) 81% Ti + 10% Al + 9% C. Mechanical activation of these compositions leads to an increase in the diffuse background, a decrease in the intensity of diffraction reflections of mixture components and a broadening of peaks, as well as micro-deformations. Depending on the ratio of components, the structural parameters can either increase in comparison with the initial ones, or decrease. The effect of gamma radiation with a dose rate of 1 Gy/s and accumulated dose of 3·104 Gy on the mechanocomposites of the Ti-Al-C system causes unsystematic change in crystal lattices of elements, which can be explained by radiation-stimulated diffusion. Gamma-irradiation also reduces micro-deformations that occur after mechanical activation, while crystallites of the components remain nanoscale.

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Influence of High Energy Impact on the Structural-Phase State and Tribological Properties of the Surface Layer of Metal-Ceramic Composite Materials

Journal of Surface Investigation X-ray Synchrotron and Neutron Techniques ◽

10.1134/s1027451018030151 ◽

2018 ◽

Vol 12 (3) ◽

pp. 485-491

Author(s):

V. E. Ovcharenko ◽

K. V. Ivanov ◽

Yu. F. Ivanov ◽

A. A. Mohovikov

Keyword(s):

Surface Layer ◽

Composite Materials ◽

Ceramic Composite ◽

Phase State ◽

Structural Phase ◽

High Energy ◽

Structural Phase State ◽

Energy Impact ◽

Metal Ceramic ◽

Ceramic Composite Materials

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Influence of High-Energy Milling in Hydrogen on the Structural-Phase State of Alloys Based on the Laves Phases

Materials Science ◽

10.1007/s11003-019-00245-8 ◽

2019 ◽

Vol 55 (1) ◽

pp. 9-16

Author(s):

Yu. B. Basaraba ◽

Т. М. Zasadnyi ◽

Т. І. Lutsyshyn ◽

І. E. Marchuk

Keyword(s):

Phase State ◽

Structural Phase ◽

High Energy ◽

Laves Phases ◽

Structural Phase State ◽

High Energy Milling ◽

Milling In Hydrogen

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Structural-Phase State and Strength Properties of Pressure-Synthesized Ni3Al Intermetallic Compound

Materials Science Forum ◽

10.4028/www.scientific.net/msf.906.95 ◽

2017 ◽

Vol 906 ◽

pp. 95-100 ◽

Cited By ~ 6

Author(s):

V.E. Ovcharenko ◽

E.N. Boyangin ◽

A.P. Pshenichnikov ◽

T.A. Krilova

Keyword(s):

Grain Size ◽

Intermetallic Compound ◽

Powder Mixture ◽

Delay Time ◽

Phase State ◽

Structural Phase ◽

Strength Properties ◽

Synthesis Product ◽

Structural Phase State ◽

High Temperature Synthesis

The article studies dependences of grain size in Ni3Al intermetallic compound synthesized under pressure in 3Ni+Al powder mixture in conditions of bulk exothermal reaction upon pre-pressure acting on the powder mixture and upon a delay time of applying pressure to a high-temperature synthesis product. It is proved that an increase in the pre-pressure on the parent powder mixture reduces the grain size, and an increase in the delay time increases the grain size in the synthesized intermetallic compound. Reducing the grain size from 10 to 1.75μm increases the strength of the intermetallic compound under pressure from 336 to 482 MPa (1.4 times).

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