OA17348A - Nanostructure of a revitalizing agent and method for producing a stable form of a nanostructure of a revitalizing agent. - Google Patents

Abstract

The invention is considered as nanotechnology and as a method to obtain nanomaterials which may be used in lubricant compositions for treatment of friction units as well as for restoration of friction surfaces of mechanisms' and machines' parts. The revitalizant nanostructure is a new step in a technical progress which is connected with decrease of typical sizes of materials and their transition to the level of nanophase materials, the properties of such materials may have essential changes, herewith new properties of individual nanoobjects and generated nanoobject formations arise which are substantial for technical application in different technical areas. In the base of stated technical decision there is an objective to obtain the revitalizant nanostructure out of the dehydration products of the natural and/or synthesized hydrates and/or their mixtures, at the temperature of constitution water elimination and the temperature of dehydration product stabilization 300°C - 1200°C, which in stable condition contains the oxides of the range MgO and/or SiO2 and/or AI2O3 and/or CaO and/or Fe2O3 and/or K2O and/or Na2O, where the revitalizant nanostructure consists of nanograin and a binding stage, in which according to the suggested invention the nanostructure has structureless grenade shape, the size of which spans 100 - 100000 nm, the size of nanograin spans 2 - 200 nm, in which additionally according to the invention, the elimination of constitution water proceeds at the temperature of 300 1000°C, and stabilization of the dehydration product proceeds at the temperature of 1000 1200°C, hereby the structureless grenade shape of the revitalizant nanostructure is formulated from the product mixture of natural and/or synthesized hydrates, and the binding stage of structureless grenade shape is formulated by uniform mixture of several oxides of the range MgO and/or SiO2 and/or AI2O3 and/or CaO and/or Fe2O3 and/or K2O and/or Na2O, where nanograin of structureless grenade shape is formulated by one or several oxides of the range MgO and/or SiO2 and/or AI2O3 and/or CaO and/or Fe2O3 and/or K2O and/or Na2O, with nanoparticle hardness of 7-10 units on the Mohs scale. In the base of stated technical decision there is an objective to upgrade the way of obtaining a stable form of the revitalizant nanostructure, including the dehydration stage of natural and/or synthesize hydrates and/or their mixtures at the temperature of constitution water removal from 300 to 1000°C where the indicated oxides have been chosen from the groups which include MgO and/or SiO2 and/or Al2O3 and/or CaO and/or Fe2O3 and/or K2O and/or Na2O, the supply of the obtained product onto the friction surface or in friction zone where, according to the stated invention, the formation of the stable form of the revitalizant nanostructure additionally includes the stabilization stage (getting a structural permanent form) that is carried out after the dehydration stage. The stabilization stage includes stabilization of the dehydration product at the temperature of 1000 - 1200°C over a period of 1 - 3 hours, thereby the revitalizant nanostructure stabilizes over the range 100 - 100000 nm, and the stage of obtaining a stable geometrical form (form of rolling) that takes place after stabilized dehydration product supply onto the friction surface or friction zone, and which depends on the lubricating or friction mode, when h ≤ Ra ≤ size of the stabilized revitalizant nanostructure, where h- is the thickness of lubricating layer or the distance between friction surfaces, Ra - the roughness of the surface in which additionally, according to the invention, the stage of obtaining a stable geometrical form of revitalizant nanostructure (form of rolling) takes place at boundary lubricating mode or boundary friction mode, where h ≤ Ra ≤ size of the stabilized revitalizant nanostructure or s stage of obtaining a stable geometrical form of the revitalizant nanostructure (form of rolling) takes place at a mixed lubricating or friction mode, when h = Ra ≤ size of the stabilized revitalizant nanostructure or the stage of obtaining a stable geometrical form of the revitalizant nanostructure (form of rolling) takes place at dry friction mode when h tends to 0, Ra ≤ size of the stabilized revitalizant nanostructure. To the authors' opinion, the existence of the stage of the revitalizant nanostructure stabilization and the stage of formation of the stable forms of rolling in the friction zone leads to restoration of the friction surfaces at the cost of carbidization of the surface layer which transfers it into active nanostructured condition (process of revitalization), and in addition the revitalizant nanostructure actually forms "rolling bearings" which stimulate stabilization of the friction surface layers and friction minimization over the whole period of the friction surfaces service.

Description

The invention relates to the nanotechnology, namely to possible forms of nanostructures and to the methods of obtaining such nanomaterials which can be applied in lubricating compounds for treatment of friction units as well as for restoration of friction surfaces of mechanisms and vehicles parts.

The common knowledge is that in view of decreasing of characteristic dimensions of materials and their conversion into level of nanophase materials the properties of such materials may be subject to substantial changes, therewith separate nanoobjects and organised formations of nanoobjects acquire new properties which are essential for technical application in different technical fields.

The common knowledge includes, for example, the technical solution Suspension of Organic-Inorganic Nanostructures Containîng Nanoparticles of Noble Metals (Patent of Russian Fédération No. 2364472 dated October 11, 2007), according to which the nanostructure is implemented as a polycomplex in a two-phase reaction System consisting of two voluminous contacting immiscible fluids, therewith the polycomplexes comprise organic molécules containîng 2 or more amino groups as well as particles of precious metals.

The proposed technical solution, being declared, aims at deriving the revitalizant nanostructure (lubricating compound) from déhydration products of natural and/or synthesized hydrates and/or their mixtures at the température of bound water removal and the température of déhydration product stabilization ranging from 300 °C - 1200 °C, which in stable state contains oxides of sériés MgO, SiO2, A12O3, CaO, Fe2O3, K2O, Na2O, which consists of a nanograin and a binding phase and is distinctive in that the nanostructure is of amorphous pomegranate-like form, which dimensions are in the range of 100 - 100000 nm while the dimensions of the grain range from 2 to 2000 nm, taking into account that bound water removal is taken place at the température of 300 °C - 1000 °C depending on the final material, and déhydration product stabilization takes place at the température of 700 °C - 1200 °C, and the obtained amorphous pomegranate-like form of the revitalizant nanostructure is produced of mixtures of déhydration products of natural and/or synthesized hydrates and the hardness of nanoparticles makes ~ 7-10 units on the Mohs scale.

The state of the art regarding the method of obtaining the revitalizant nanostructure in the stable form consists in the fact that the method of obtaining nanoparticles cannot be separated from methods of their stabilization.

The known example is Method for Producing Nanoparticles (Patent of Russian Fédération No. 2233791 dated March 26, 2002), which includes processes of synthesis of nanoparticles distinctive in that nanoparticle synthesis is made under chemical influences or chemical and physical influences or combinations thereof in the monomolecular layer on the surface of the fluid phase.

There exists the technical solution Method of Obtaining the Suspension of OrganicInorganic Nanostructures (Patent of Russian Fédération No. 2364472 dated October 11, 2007), which contains nanoparticles of noble metals which includes création of the reaction System which contains metallic molécules of precursors and ligands, introduction of a reducing agent thereto and synthesis of nanoparticles which is distinctive in that a two-phase reaction System is formed which consists of two contacting voluminous immiscible fluids - hydrophobie and water phases, at that organic molécules containing 2 or more amino groups act as ligands, metallic molécules of the precursor are dissolved in the hydrophobie phase and the ligands - in the water phase, wherein the reducing agent is introduced.

While investigating the state of the art of method for obtaining the stable form of revitalizant nanostructure, it was found out that the derived formations can be used in production of lubricating compounds consisting of a lubricating medium and a déhydration product of hydrates of natural minerais or mixtures of naturel minerais or synthesized hydrates, wherein the déhydration product contains oxides of MgO and/or SiO2 and/or A12O3 and/or CaO and/or Fe2O3 and/or K2O and/or Na20, obtained after removal of bound water and destruction of the crystal lattice at the température being below 900 °C, wherein due to the fact that the stable phase of the déhydration product is achieved through décomposition of natural minerais or a mixture of natural minerais or synthesized hydrates at the température hold in the range from 900 °C to 1200 °C, which provides obtaining the décomposition product grain with the size of 100 - 100000 nm, the proposed lubricating compound can be used in machine-building industry and in different fields of engineering both in case of initial treatment of friction units and during operational period of various mechanisms and vehicles, particularly to extend time between overhauls or during maintenance and repairs.

Physical and chemical properties of the material contaîning metall particles largely dépend on the nature of métal, form and size of the particles, their orientation, amount and distribution in the structure of the material. The properties of the métal nanoparticles, particularly their form, crystalline structure, crystallinity degree as well as optical, electronic and catalyst properties substantially dépend on their size.

Nowadays in the scientific and technical literature there are quite many descriptions which deal with different methods of synthesis of precious métal nanoparticles, including various methods of synthesis of colloïdal nanoparticles of precious metals in a voluminous one-phase fluid reaction System based on réduction of salts or complexes of métal ions in the presence of stabilizing ligands.

The proposed technical solution, being declared, aims at improving the method for obtaining the stable form of the revitalizant nanostructure, which comprises déhydration of naturel and/or synthesized hydrates and/or their mixtures at the température of bound water removal from 300 °C to 1000 °C; stabilization of the déhydration product at the température ranging from 700 °C to 1200 °C within 1-3 hours, mixing of the derived product with the lubricating medium, wherein the stated oxides are selected from the groups that include MgO, SiO2, A12O3, CaO, Fe2O3, K2O, Na20, introduction of the obtaîned mixture onto the friction surface within the friction zone according to which the stable form of the revitalizant nanostructure which size being in the range from 100 to 100000 nm and is transferred into the rolling stable form depending upon the friction rate on the friction surface and température in the friction zone, at that the time of transfer into the stable rolling form of the revitalizant nanostructure dépends upon roughness of the surface being treated and the rate of friction unit wear.

The proposed method for obtaining the stable form of the revitalizant nanostructure is technologically bound with the method for producing the lubricating compound itself, which comprises the process of déhydration of hydrates of métal and/or non-metal oxides at the température from 300 °C to 1200 °C, the process of mixing the obtaîned product with a lubricating medium, wherein the stated oxides are selected from the groups which include MgO, SiO2, A12O3, CaO, Fe2O3, K2O, Na2O, and the process of stabilization of the déhydration product or decay product, which is implemented through coordinated exposure to the température from 700 °C to 1200 °C and time hold from 1 to 3 hours.

FIGs. 1-7 represent the stable forms of the revitalizant nanostructure.

FIG. 1 schematically represents the revitalizant nanoparticle, wherein the controllable size is shown for friction units with different levels of initial roughness. Conventionally the revitalizant nanoparticle can be represented in form of a pomegranate, wherein its active particles (l) with the size of 2...2000 nm are presented in form of grains. The binding phase (2) prevents the particles from contacting. The hardness of the active revitalizant particles is approximately 8-9 units on the Mohs scale and their durability exceeds the durability of the binding phase. ITence, such particle can be ground to the tiniest grain.

Hydrates, which are natural nanomaterials in their original state, are used as initial substances for obtaining the revitalizant nanostructure. As a resuit of déhydration of such substances, i.e. during removal of bound water from the crystal lattice, two-phase conglomerated formations consisting of nanoparicles with the size of 2-200 nm instead of the initial substance are obtained. The above stated facts are confirmed through the conducted electron-microscopic researches (FIG. 2, 3), wherein FTG. 2 is the light-field electron-microscopic picture of the initial particle of the hydrate of the revitalizant nanostructure on the substrate of isomorphous carbon, which demonstrates nanoscale dimensionality of the revitalizant (~300 nm) and integrity of the initial particle of the hydrate. FIG. 3 is the light-field electron-microscopic picture of the hydrate particles on the substrate of isomorphous carbon after the process of déhydration. This picture testifies that removal of bound water from the hydrate particle leads to the destruction of its initial integrity and formation of two-phase conglomerated components in form of a pomegranate. FIG. 4 and 5 demonstrate the process of carbidization of the treated surface or friction surface subdivided into the following stages.

Stage one. Interaction between the revitalizant and the surface materials during formation of the modified coating can be described as the formation of a ceramic-metal coating consisting mainly of métal carbides. It was experimentally established that at this stage nanoscale dimensionality of the revitalizant nanoparticles ensures the dimensional effect of their mechanical interaction with the métal surface. This effect consists in the fact that the initial size of the revitalizant particles corresponds in scale to the sizes of the surface defects (graininess, microroughness, etc.). Such interaction causes nanoscale plastic deformation of métal and conversion of the surface layer into the active nanostructured state. This process is accompanied by intensive grinding of the métal grains, increase in density of their boundaries, improvement of conditions for carbon diffusion into the surface (vertically) and into the grains (horizontally) (FIG. 4).

Thus, according to the proposed technical solution, the revitalizant nanoparticles act as pressure concentrators. The pressure of the revitalizant particles in the contact patterns with the surface is high, as its value is inversely proportional to the square of the particle size (2200 nm), i.e. the nanostructured revitalizant forms unique P and T (pressure and température) conditions for intensive diffusion of carbon atoms inside the surface. These conditions facilitate formation of carbides from the solution of carbon in iron (low-temperature carbidization). Such interaction is achieved owning to the nanoscale dimensionality of the revitalizant.

FIG. 5 (the scheme of interaction between the revitalizant and the friction surface or restoration and carbon saturation of the surface layer with subséquent formation of carbides) shows surface hardening by the revitalizant nanostructures during which, apart from casehardening (carbidization) of the surface, another unique nanodimensional phenoinenon and its surface hardening takes place. This hardening is peculiar due to the formation of compressive stresses of constant signs through the whole depth of the modified layer. Traditional surfaceplastic deformation of parts is performed using shot, steel balls, rolling, etc. Such mechanical strengthening créâtes residual compressive (positive) stresses in the surface layer of parts, increasing fatigue strength endurance, improving surface hardness, reducing its roughness, removing surface microdefects. Revitalizant nanostructures hâve been used by XADO Chemical Group (Kharkiv, Ukraine) when using the XADO-technology, where revitalizant nano-sized particles (being not abrasive in this case) act as deformation-strengthening éléments. Formation of the considérable compressive stresses in the surface layer is confirmed by the data of X-ray strain metering (sin2\|/ method). At the same time, the effects of surface strengthening by application of the revitalizant are transferred to the nanolevel. Thus, compressive stresses which may be obtained only by shot treatment occur herein due to the nanoparticle, being not abrasive and is présent in the lubricant compound over the whole period of revitalization. Interaction of the revitalizant particle under P, T factors (high spécifie pressures and températures) deforms the part surface. Therewith, it strengthens and smoothens the part surface; its roughness is decreased to nanolevel.

As it is évident from the description of the proposed technical solution, the revitalizant nanostructure and the method of obtaining the stable form of the revitalizant nanostructure are new, they possess the inventive level and are suitable for industrial application.

Authors

V.L. Zozulya

S.L. Zozulya

S.N. Alexandrov

On behalf of the Applicants Intellectual Property Représentative Patent Agent in Ukraine

A.G. Adamenko

Claims (11)

1. The revitalizant nanostructure is formulated from déhydration products of natural and/or synthesîzed hydrates and/or their compositions at the température of constitution water removal and the température of déhydration product stabilization from 300°C to 1200°C, in its stable condition it contains the oxides from the range MgO and/or Si02 and/or A12O3 and/or CaO and/or Fe2O3 and/or K20 and/or Na20, including nanograin and the binding stage, the différence is that nanostructure has structureless grenade shape, the size of which spans 100 100000 nm, the size of nanograin spans 2 - 200 nm.

2. The revitalizant nanostructure, according to p.l, differs by the température of constitution water élimination 300°C - 1000°C.

3. The revitalizant nanostructure, according to p.l, differs by the température of déhydration product stabilization 1000°C - 1200°C.

4. The revitalizant nanostructure, according to p.l, differs by the thing that the structureless grenade shape of the revitalizant nanostructure is formulated from the product mixture of natural and/or synthesîzed hydrates.

5. The revitalizant nanostructure, according to p.l, differs by the thing that the binding stage of the structureless grenade shape is formulated by one or several oxides of the range MgO and/or SiO2 and/or A12O3 and/or CaO and/or Fe2O3 and/or K2O and/or Na2O.

6. The revitalizant nanostructure, according to p.l, differs by the thing that nanograin of the structureless grenade shape is formulated from one or several oxides from the range MgO and/or SiO2 and/or A12O3 and/or CaO and/or Fe2O3 and/or K2O and/or Na2O.

7. The revitalizant nanostructure, according to p.l, differs by the nanoparticle hardness of-7-10 units on the Mohs scale.

8. The method for producing a stable form of a nanostructure of a revitalizing includes a déhydration stage of natural and/or synthesîzed hydrates and/or their mixtures at the température of constitution water removal from 300 to 1000°C, where the stated oxides are chosen from the groups which include MgO and/or Si02 and/or A12O3 and/or CaO and/or Fe2O3 and/or K2O and/or Na20, the introduction of the obtained product onto the friction surface or to the friction zone, differs by formation of the stable form of the revitalizant structure, additionally it contains the stage of obtaining a structural-permanent form (stabilization stage), which includes stabilization of déhydration product at the température from l000°C to 1200°C during 1-3 hours, and revitalizant nanostructure stabilizes over the range 100 - 100000 nm, and the stage of obtaining a stable geometrical form (form of rolling), which takes place after application of the stabilized déhydration product to the friction surface or to the friction zone, and which dépends on lubricating friction mode, when : h < Ra < size of stabilized revitalizant nanostructure, h - lubricating layer thickness or the distance between friction surfaces, Ra - surface roughness.

9. The method for producing a stable form of a nanostructure of a revitalizing according to p.8 differs by the thing that the stage of obtaining a stable geometrical form of the revitalizant nanostructure (form of rolling) takes place at limiting lubricating friction mode, when h < Ra< size of stabilized revitalizant naiiostructure.

10. The method for producing a stable form of a nanostructure of a revitalizing according to p.8 differs by the thing that the stage of obtaining a stable geometrical form of the revitalizant nanostructure (form of rolling) takes place in combination lubricating mode or combination friction mode, when h = Ra < size of stabilized revitalizant nanostructure.

11. The method for producing a stable form of a nanostructure of a revitalizing according to p.8 differs by the thing that the stage of obtaining a stable geometrical form of the revitalizant nanostructure (form of rolling) takes place in dry friction mode, where h tends to 0, Ra < size of stabilized revitalizant nanostructure.