E. A. Petrikova

Numerical Simulation of Thermal Processes Involved in Surface Alloying of Aluminum with Titanium by an Intense Pulsed Electron Beam

The temperature fields arising in a Ti film – Al substrate system and bulk Ti specimen irradiated with a submillisecond intense electron beam are calculated in the one-dimension approximation. It is found that the temperature fields in the irradiated bulk Ti specimen and Ti film – Al substrate system differ greatly. Electron beam irradiation conditions which allow solid-phase and liquid-phase alloying of aluminum with titanium are defined

Fractography of the fatigue fracture surface of silumin irradiated by high-intensity pulsed electron beam

Irradiation mode has been revealed allowing to increase the silumin fatigue service life in three times, it was established that this fact is caused by the formation of multi-modal, multi-phase, submicro - and nano-structure able to lead to a significant increase in the critical length of crack.

Structure and properties of surface alloys synthesized by pulsed electron-beam treatment of a coating-substrate system

Nanostructured multiphase Al-Ti-Cu surface alloys are synthesized by pulsed electron-beam treatment of the coating-substrate system. In certain conditions, the strength and tribological characteristics of the initial material may be greatly improved.

Surface layer of commercially pure VT1-0 titanium after electric-explosion alloying and subsequent treatment by a high-intensity pulsed electron beam

The structure, phase composition, and mechanical, tribological, and corrosional properties of commercially pure VT1-0 titanium are investigated after electric-explosion alloying and subsequent treatment by a high-intensity pulsed electron beam. Treatment conditions that greatly increase the properties of the titanium are identified. The physical factors at work here are considered.

Surface of high-chromium steel modified by an intense pulsed electron beam

The formation of nanostructural multiphase surface layers in high-chromium 12Х18Н10Т and 20Х13 stainless steel under the action of an intense pulsed electron beam in a SOLO system is studied. The Fe–Cr–C system is thermodynamically analyzed. Alloying Fe–Cr alloys with carbon considerably changes their structural and phase state and determines the regions of existence of the carbides M23C6, M7C3, M3C2, and M3C with α and γ phases. The temperature field formed in the surface layer of the steel under the action of the electron beam is numerically calculated. When the energy density of the electron beam is 10 J/cm2, regardless of the pulse length of the electron beam (50–200 μs), the maximum temperature at the sample surface corresponding to the end of the pulse is less than the melting point of the steel. The structure and the mechanical and tribological properties of the surface layer of high-chromium 12Х18Н10Т and 20Х13 steel formed under the action of the intense pulsed electron beam are investigated. It is found that electron-beam treatment of the steel with melting and subsequent high-speed crystallization is accompanied by solution of the initial carbide particles of composition M23C6—specifically, (Cr, Fe)23C6—and hence saturation of the crystal lattice in the surface layer with carbon and chromium atoms. In addition, submicronic cells of dendritic crystallization are formed, and nanoparticles of titanium carbide and chromium carbide are deposited. Overall, electron-beam treatment improves the surface and tribological properties of the materials. For 12Х18Н10Т steel, the hardness of the surface layer is increased by a factor of 1.5 and the wear resistance by a factor of 1.5, while the frictional coefficient is decreased by a factor of 1.6. For 20Х13 steel, the microhardness is increased by a factor of 1.5 and the wear resistance by a factor of 3.2, while the frictional coefficient is decreased by a factor of 2.3.

An increase in fatigue service life of eutectic silumin by electron-beam treatment

Silumin of the eutectic composition is treated by a high-intensity electron beam and a multiple increase in material fatigue service life is revealed. The structure of the modified layer and the failure surface of silumin subjected to fatigue multicycle destruction tests are investigated by scanning electron microscopy. Factors responsible for an increase in its fatigue service life are established and analyzed.

Structure, phase composition, and properties of the titanium surface modified by electron-ion-plasma methods

The results of studying the phase and elemental compositions, imperfect substructure, and mechanical and tribological properties of commercially pure VT1-0 titanium subjected to combined treatment, which involves nitriding in low-pressure gas-discharge plasma and nitride coating deposition, are presented. The regularities are analyzed, the physical mechanisms of structural modification are discussed, and the optimal impact modes allowing a multiple increase in the microhardness and wear resistance of the material are revealed.

Modification of the titanium film–aluminum substrate system by a high-intensity pulsed electron beam with a submillisecond duration

Numerical simulation of the thermal processes that occur during doping of an Al surface with titanium by the method of liquid-phase mixing of a film–substrate system using an intense pulsed electron beam is carried out. As a result of our studies, it is shown that melting of the Ti-film–Al-substrate system makes it possible to form a multiphase submicrocrystalline structure with high strength and tribological properties in the surface layer.

Modification of the surface layer of the system coating (TiCuN)/substrate (A7) by an intensive electron beam

In order to study the conditions of modification of the surface layer of the system coating (TiCuN)/substrate (A7) an analysis of processes occurring in the surface layer of the system wear-resistant coating/substrate irradiated by an intensive pulsed electron beam at a submillisecond exposure time has been carried out on the example of aluminum and titanium nitride. Irradiation has been carried out under conditions ensuring melting and crystallization of the surface layer of the material by a nonequilibrium phase diagram. It has been experimentally established that irradiation of the system coating (TiCuN)/substrate (A7) by an intensive electron beam is accompanied by changes in the phase composition of the material. It is evident that nanostructuring of the aluminum layer adjacent to the coating, and formation in it of nitride phase particles will contribute to hardening of the surface layer of the material, creating a transition sublayer between a solid coating and a relatively soft volume. The carried out analysis shows that binary nitrides based on TiN1-x are most likely to form under nonequilibrium conditions, since the homogeneity range of this compound is rather large. On the other hand, formation of the ternary compound Ti3CuN, which can be formed after an arc plasma-assisted deposition of titanium nitride of the composition TiCuN and by the subsequent intensive pulsed electron beam exposure, cannot be excluded.

Hardening of the Surface Layer of Silumin by Electron Beam

In the present work has been carried out the treatment of silumin by high-intensity electron beam with different density of the input energy. The structure and phase composition of surface layer have been studied by the methods of X-ray diffraction and electron microscopy both scanning and diffraction transmission. The mechanisms are responsible for improvement of properties of modified material have been revealed. It has been shown that electron beam treatment of silumin is accompanied by the formation of multilayer submicro-and nanocrystalline structure and result in increasing the microhardness of the surface layer (towards the core) is ~ 3.5 times, the Youngs modulus in a ~ 1.4 times, the ultimate bending strength (in ~ 1.2 times) and tensile strength (in ~ 1.4 times), the bending plastic limit (in ~ 1.2 times) and tensile (in ~ 1.8 times).