# Introduction o improve the physical and mechanical characteristics of the surface layers of parts in order to increase the durability and reliability of used durable and anti-friction coatings applied by various methods. Surface properties used in modern engineering austenitic stainless steels and titanium alloys can be improved by application of multilayer wear-resistant and anti-friction coatings. As such coatings have been used transition metal compounds IY-YI of the periodic system (dichalcogenides, nitrides, carbides, oxides), applied vacuum ion-plasma methods. Having a range of features of the crystal structure and properties of high anisotropy in various crystallographic directions resulted in widespread use for these purposes dichalcogenides of transition metals. Very promising and has several advantages are vacuum ionplasma methods of applying such coatings based on ion (cathode) sputtering. Development of the theory of managing the growth of coatings based on transitionmetal dihalcogenides and their relationship with the technology application, explain the process of the formation of coatings with high tribological properties and mechanism of anti-friction properties, as well as comprehensive investigations of the crystal structure and physical properties of coatings are important scientific and technical challenge. Author: Russian Academy of Sciences, Joint-Stock Company "Technom-T", Moscow, Russia. e-mail: technomt@technom-t.ru II. # Subjects and Methods Coatings based on dichalcogenides of transition metals from Groups IV-VI of the periodic table, inparticular, molybdenum and tungsten disulfides and diselenides (MoS 2 , MoSe 2 , WS 2 , and WSe 2 ), were deposited via the HF cathode sputtering technique described in [1][2][3][4][5][6]. In disk-on-sphere friction tests, the specific load and the constant sliding rate were ~105 N/cm2 and 0.019 m/s, respectively [1][2][3][4][5][6]. The coatings were formed on polished samples fabricated from compact Al 2 O 3 ceramics and SH-15 and 12H18N10T steels. The crystalline structure of the coatings was investigated by means of reflection electron diffraction using an EMR-102 electronograph, and the surface morphology was examined using JXA-841 and JSM-35C electron microscopes. The elemental composition of the prepared coatings was analyzed via characteristic X-ray spectroscopy( a JEM-100C instrument equipped with a CEVEX attachment) and X-ray photoemission spectroscopy (an ESCALAB-5 device). # III. # Experimental Results To protect work surfaces from wear of friction pairs technology for production of wear-resistant antifriction coatings of variable thickness with high tribological properties [2], is an effective means of protecting the parts, especially made of corrosionresistant austenitic steels or titanium alloys from wear. Used in modern engineering austenitic stainless steels and titanium alloys have a number of advantages, but these materials are due to the peculiarities of physical and mechanical properties tend to grasp, followed by catastrophic wear, especially under high vacuum. From the coating process parameters to be considered the most important temperature substrate further bias potential applied to the charge of the sample holder, as well as alloying of the applied coating by applying to the working chamber of reactive gas (or gas mixture) and a complex manufacturing replaceable target structure. Studies have found that when the temperature of the substrate were formed quasi-amorphous, polycrystalline or textured coatings. Crystallite orientation axis textures [10 1 0], perpendicular to the substrate surface was observed for MoS 2 , MoSe 2 , WS 2 , WSe 2 in the temperature range 473-973K, and the axis [11 2 0] -to MoS 2 at T = 673-773K [1-4] . Texture growth with the axis [10 1 0] formed in all dichalcogenides, whereas the texture with the [11 2 0] T was detected in the coatings of molybdenum disulfide in the temperature range 673-773K. Dependence of the structure from the location of the samples on the plate of holder of substrates. Research was conducted at the location of coating growth patterns in different places (in the center and the periphery) of the plate of substrate holder. It was found that the location of the sample in the center of the plate o? holder crystallites grow with a preferred orientation in the form of texture with the axes [1010] and [11 2 0], with appropriate substrate temperatures (Fig. 1). The axis [0001] was completely disoriented in a plane parallel to the substrate surface. At a distance from the center to the periphery of the board was observed smooth tilting axes [10 1 0] and [11 2 0] direction crystallite orientation with simultaneous central axis [0001] at the center of the radius of the sample holder, wherein the angle of inclination of the axes reached up to 30 0 . Coincidence direction of the electron beam in the column c electronograph radius vector of the center of the plate leads to a symmetric diffraction pattern, and when the sample is moved parallel to the beam view of the diffraction pattern remains unchanged. The results obtained are confirmed by studies of surface morphology of the coating (Fig. 2). Micrograph shows that the crystallites are oriented with a small angular spread. With increasing distance from the center of the board, they form closed concentric circles. This morphology of the films stored at different coating dichalcogenides (MoSe 2 , WS 2 , WSe 2 ) (Fig. 1,2). Range of crystallization under the same deposition conditions (substrate temperature varied only) shifted into a zone of higher temperatures. The highest transition temperature of the amorphous structure to a crystalline textured observed for tungsten diselenide WSe 2 (Fig. 3). Studies shows, that the texture with the axes [1010] and [11 2 0] in the coatings on the basis of textures are dichalcogenides growth, since they do not occur in its infancy, and in the later stages. For example, if a molybdenum disulfide coating on polished samples of steel or Al [0001] along the radii from the center of the plate (Fig. 4). As follows from the diffraction pattern, the second axis [0001] at an angle of crystallites to a surface of the substrate up to 15 0 and the principal axis is tilted texture [10 1 0] toward the center respectively. Improving tribological properties of the coatings is possible with the changes in technology application. For example, increasing the hardness of the substrate reduces the coefficient of friction and increased durability of coatings based dichalcogenides. Improved tribological characteristics occurs when doping atoms of molybdenum disulfide additional element. The combination of applying a wear-resistant outer sublayer with doping atoms antifriction layers additional element can significantly improve the tribological characteristics. Doped coating. Were obtained from the doped molybdenum disulfide coating composition MoS2Dx that appearance is not much different from conventional coatings MoS2. As dopant D can be selected elements or compounds that do not form strong (chemical) bonds with the host lattice MoS 2 . When friction testing scheme disk sphere coatings with a hexagonal crystal structure of molybdenum disulfide 2H-MoS 2 were obtained sufficiently low coefficient of friction, but in general the corresponding friction natural molybdenum disulfide. However, friction tests in the same conditions coating composition MoS 2 D x led to getting unusually low values of the coefficient of friction (effect of superlow friction) (Fig. 5). Electron diffraction studies of coatings MoS 2 D x showed that there was a significant increase them ¬ methods and by electron-beam evaporation (REP) coatings of pure molybdenum and chromium and their compounds such as nitrides and oxides with body-centered cubic lattice, in the center of the plate to form a coating samples with texture axis [110]. As the distance to the periphery was a gradual slope texture axis [110] to the center (up to the transition to the texture of a [111] axis) while being oriented to the [100] direction along radii from the center of the plate. I.e. also in this case maintained a similar growth mechanism. Microphotographs (Fig. 4) is not visible almost two-dimensional elongation of the crystals, as in the case of transition-metal dichalcogenides, due to the lack of such a large anisotropy of the surface energy of crystal faces. Cr 2 O 3 coating had a hexagonal structure, space group D 6 3d -3RS. Crystal growth Cr 2 O 3 obey the same law -in the center of the plate texture is formed with the axis [10 1 0] perpendicular to the substrate surface. crease the lattice period along the axis c (up to 1.38-1.43 nm against 1.2295 nm for compounds with a stoichiometric composition (hexagonal 2H-MoS 2 ) in practically constant period along the a axis . Increasing the distance between the layers when placing the D atoms in the inter-packet spaces due to the fact that the energy of the van der Waals interaction varies in proportion to ~ r -6 , should lead to a decrease in this interaction practically an order of magnitude [1][2][3][4][5][6]. ume XIV Issue II Version I 2 ; 2 -MoS 2 Ð?" ? ,; 3 - (Mo 2 N-M k N m X n -MoS 2 ); 4 -(Mo 2 N-M k N m X n -MoS 2 Ð?" ? ) Studies were carried out properties of the composite anti-friction wear-resistant coating based on tungsten diselenide and disulfide WS2 and WSe2, deposited on a substrate made of structural strength titanium alloy VT23, and gallium alloyed coating WS2Gax and WSe2Gax (Fig. 7), deposited on a substrate by reactive electron-beam plasma spraying (RAP) as wear Cr 2 O 3 sublayer thickness of 2.0-2.5 microns. # Disscussion of Results Based on the concepts of migration processes of atoms on the surfaces of solids, along with a rough structure of atomically smooth areas, created a generalized mathematical model of the application and obtained the properties of ion-plasma coatings, determining their structure during application and physico-mechanical properties of the coatings when applying such coatings [1][2][3][4][5][6]. # Volume XIV Issue II Version I On the basis of established generalized theoretical model: -Application developed atomic cluster model of crystal growth in the coating vapor deposition or the flow of sputtered particles in vacuum, caused by the presence of two phases on the surface of the atoms (condensed and migratory) and phase transitions occurring in a temperature range on the substrate; -Proposed and experimentally substantiated mechanism of action of anti-friction coatings doped dichalcogenides explaining the effect of superlow friction solid laminates and defining opportunities for ultralow friction. The essence of atomic cluster model of crystal growth is as follows: Atoms in the adsorption sites in the "sedentary state" on a solid surface are condensed phase. Migratory phase can be represented as two-dimensional gas on the surface that follows an exponential distribution of particle energies (Maxwell distribution). The ratio of the two phases determines the structural state of the growing coating. Then the crystal size L in a growing number of the coating is determined by the ratio of the condensed phase (defined by B) and the migratory phase (defined by C). L = A [(1-?)? + ??] 1\2 / 1 / where A -value depending on the structure and properties of deposited material. Flux of sputtered material in vacuum ion-plasma deposition methods, along with the atomic phase contains a certain number of cluster phase consisting of N atoms (for N = 1,2,3 and more). Such polarized clusters in the coating on the surface can be oriented properly and around the center of the board and play a role in the crystallization step coverage, identifying the growing structure. Decisive influence should provide flow distribution of the deposited particles on the cosine law. Thus facets with the highest surface energy should rise with a slope in the direction of maximum density of flux, which particles with the cosinusoidal distribution of the target is in the center. Under the influence of these factors together formed texture with two axes preferred orientation of crystallites, with properties approaching the single crystal (Fig. 1 , 2). With increasing temperature observed broadening of the distribution curve of the particle energy, the displacement magnitude of the potential barrier at higher temperatures should be an increase in the width of the crystallization. As indicated above, this occurs, for example, in the case of transition metal dichalcogenides, wherein the smallest width of the crystallization for MoS 2 (373 ... 413 K, and, most -for WSe 2 (493 ... 563 K). Therefore, when the displacement magnitude of potential barrier to absolute zero can be achieved practically hopping phase transition type crystallization (Fig. 9), which may occurs, for example, in Antifriction mechanism of action, explaining the occurrence of the effect of superlow friction solid laminates based dichalcogenides and defining high tribological properties of the coatings during friction, cracking easily justified crystals on planes (0001) dichalcogenide packages where there are weak van der Waals interactions of the type, not related to the exchange or socialization electrons, and allow ease of sliding such packets to each other. Terms of superlow friction coefficients are presented in [1][2][3][4][5][6]. Determining factor in this process is to not break the binding energies of Ur in the contact zone, and the shift of the atomic planes overcoming potential barriers sliding over each other surfaces Ub. In the study of changes in the surface layers during friction dichalcogenides found that the structure of crystals with preferred orientation (texture ) with the axis [1010] turns into a texture with the [0001] direction perpendicular to the substrate. The emergence of superlow friction due to the presence of migratory phase on friction surfaces (0001), in a state of two-dimensional gas. In [1][2][3][4][5][6] the superconducting. # ume XIV Issue II Version I ? s = A a [(1-?)? s + ?? s ] 1\2 / 2 / where A a -value depending on the structure and properties of applied substance. The particles of this phase (atoms , molecules, clusters) can be adsorbed from the environment or introduced into the lattice of solid as it is formed . For superlow friction coefficients in normal air must shift the phase transition in the temperature range of less than 300 K , i.e. the binding energy of atoms adsorbed on the (0001) plane dihalcogenide to ensure free movement on the surface to be less than the kinetic energy of the atom under normal conditions. Mass transfer without heat loss and energy costs possible along the equipotential surface. Having alloy monolayers of particles on the surfaces of friction increases the distance between the planes (0001) and reduces the interaction energy between the layers U r . Such particles when opportunities for migration of the diffusion surface (0001) provide ease of sliding the opposed planes (0001) relative to each other and thus by moving the particles along the field lines of the surface ( 0001 ) arises the possibility of movement without energy dissipation. In the absence of a condensed phase is preserved only migratory phase ? s = A a (?? s ) 1\2 / 3 /, provides the effect of superlow friction. V. # Superlow Interaction between Particles Discovered physical phenomenon of mass transport along the lines of equipotential surface fields without energy dissipation in the absence of resistance forces is a process of moving the motion of matter, manifested in the form of ultra-low friction, superconductivity and superfluidity. This movement is possible under normal conditions in the form of particles moving between the solid surface along the lines of equipotential fields determined the shape and structure of the Fermi surface. An unusual feature of the motion of particles (atoms, molecules, clusters) of homogeneous singular planes (0001) dichalcogenides is uniform motion without energy dissipation. Similar phenomena have been observed to create the conditions for the movement of particles in the absence of frictional forces (superfluidity) and resistance to movement of particles (superconductivity). Intercalation dichalcogenides which are semiconductors, led to the emergence of their superconducting properties, which was a consequence of placement of dopant atoms in the interlayer spaces. Superlow friction phenomena and superconductivity observed in layered crystal structures of type dichalcogenides (MX 2 ) and diboride (MB 2 ) metals [1][2][3][4][5][6]. In magnesium diboride MgB 2 was discovered hightemperature superconductivity for a simple chemical compound critical temperature of 39 K, due to the presence in MgB 2 energy gap is not one but two . In the superconducting magnesium diboride present two kinds of Cooper pairs. Their interaction provides a sufficiently high temperature Superconductivity. It is important to note that each class has its electron pairs size, or its coherence length. Wherein magnesium diboride is only one value of the London penetration depth. In [5,6] studied the movement of negatively charged electron around the positive proton in the hydrogen system with the absence of dissipation in the uniform motion. To preserve the symmetry of Riemann and Lobachevsky fields opposite curvature in such systems, there exists the possibility of geometrical rectilinear motion of a particle in the absence of centripetal forces, the conservation movement at a constant speed . In this case, there is no change in the energy of the moving particles, i.e. the absence of dissipation. Anisotropic properties dihalcogenides and diboride preserves mass transfer phenomena dissipationless along equipotential surfaces fields determined the shape and structure of the Fermi surface at a sufficiently high temperature. Placement of dopant particles in the interlayer spaces along the plane ( 0001 ) causes the mass to move at a constant speed without dissipation of energy, i.e. there is the possibility of zero change of the interaction energy with the solid surface during the movement (a phenomenon superlow friction). High-temperature transport mass without dissipation is possible along the lines of equipotential surfaces (0001) layered anisotropic compounds in the presence of a layered structure of the solid body spaces van der Waals forces. Owing to the special status of the layered solid body -the availability of space Van der Waals forces -which are long-range forces of the dispersion and no free valence electrons capable of forming strong exchange interactions, there is the possibility of moving particles without dissipation (scattering) energy. dispersion nature, which are based on the dipoles formed by the action of collective phonon vibrations of the atoms inside the package X -M -X . These vibrations cause additive phonon vibrations associated with the polarization of opposite sign in the nearby package. Additivity of the dispersion interaction (unlike pair interactions of exchange type) causes its long-range nature of this interaction and potential decreases with increasing size of the gap by doping dichalcogenide by law r -2 , up to n = 2. 124![Figure 1 : The electron diffraction patterns of coatings MoS 2 (a, c) and WSe 2 (b, d) a thickness of 0.5 microns, applied at a temperature 523 K (MoS 2 ) and 623 K (WSe 2 ), and the location of samples in the center of the plate (a, b) and at its periphery (c, d)](image-2.png "Figure 1 :Figure 2 :Figure 4 :") 35![Figure 3 : Dependence durability of coatings based on samples of dichalcogenides Al 2 O 3 substrate temperature Scheme disc-sphere. 1-MoS 2 ; 2-MoSe 2 ; 3 -WS 2 ; 4 -WSe 2 ; I -The amorphous structure; II -Polycrystal; III -Texture; IY -Area expansion dichalcogenide MX 2 on metal and halcogen; Ub 1,2surface potential barrier and MoS 2 and WSe 2 ; Ur 1,2energy decomposition dichalcogenides MoS 2 and WSe 2](image-3.png "Figure 3 :Figure 5 :") 6![Figure 6 : Dependence of the friction coefficient on the duration of the test coatings: 1 -MoS 2 ; 2 -MoS 2 Ð?" ? ,; 3 -(Mo 2 N-M k N m X n -MoS 2 ); 4 -(Mo 2 N-M k N m X n -MoS 2 Ð?" ? )](image-4.png "Figure 6 :") 7![Figure 7 : Electron diffraction (a, b) and micrographs (x5000) (c, d, e) coating WS 2 Ga x](image-5.png "Figure 7 :") ![the time of the transition from the normal state to the Curve 1, 2 -L value specifications for compounds MX 2 (1 or 2); Curve 3 -envelope of the inflection points of the energy distribution of particles MX 2 (1 or 2); Ub 1, 2 -MX 2 surface potential barrier (1 or 2 ); Ur 1, 2 -MX 2 binding energy (1 or 2 ); PT 1 and PT 2 -phase transitions.](image-6.png "") 9![Figure 9 : Dependence characteristics L (a) and the particle energy distribution (b) of temperature](image-7.png "Figure 9 :") © 2014 Global Journals Inc. (US) Year 2014 Superlow Interaction in Layered Structures Dissipative processes are the result of the forces of resistance arising from the exchange interaction processes. ## VI. ## Conclusions -Drawing doped multilayer coatings enables obtaining ultralow friction under normal environmental conditions and increases the durability of the coating several times. -The phenomenon of non-dissipative mass transfer along the equipotential surfaces of fields that define the shape and structure of the Fermi surface. -Established that ultra low friction, superconductivity and superfluidity are related phenomena defined phase transition through the critical value of the characteristic parameter (energy potential barrier) Fermi surfaces. Creation of the composite coatings of variable thickness of the wear layer doped to antifriction of high anti-friction and wear-resistant properties. * The structure and properties of vacuum ion-plasma coatings MVNozhenkov Journal of Surface Investigation. X-ray, Synchrotron and Neutron Techniques 2014, v.8, N1 * Influence of crystalline structure on triboengineering properties of vacuum ion-plasma coatings MVNozhenkov Journal of Friction and Wear 34 2 March 2013 * The ultra-low friction of layer structures// Mechanical Engineering Research MVNozhenkov 2013 * The low friction of solids // Friction and wear MVNozhenkov 1987 8 * Weak interactions of particles in solids // Nanoengineering MVNozhenkov 2012 3 * Crystal structure and properties of coatings deposited by vacuum ion-plasma methods // Hardening and coating technology MVNozhenkov 2012