EE05848B1 - Composite material with frame and method of making the same - Google Patents

Abstract

The invention relates to composite material with required characteristics which are wear resistance and high resistance against multi-cyclic surface macro-deformations and a method of their preparation. The present composite material comprises structure 1 with tubes 2 and hinges 3 of tubes, inside of the tubes there is a hard phase 4, elastic material 5 for filling the gaps between tubes and binder 6 for fasting/fixing hard phase within tubes. The tubes have a possibility to move/rotate and because of this the load is distributed to the larger surface that provides reduction of local stresses, damages due to large possible deformations and resulting in high resistance against multi-cyclic surface macro-deformations.

Description

 TECHNICAL FIELD

The invention relates to a composite material containing a framework, more specifically a biosame, with specified properties, which is wear-resistant and has high multi-cycle surface deformation tolerance, and a method of producing such a composite material.

STATE OF THE ART

A material for the manufacture of wear-resistant tools is known (JPS55131403A). The material has a sintered base part containing 70-90% diamond crystals and the remaining part is solder containing Cu or Ag as the main components. The diamond powder is mixed with Fe, Ni, Co, Mo, Cr and Ta or their alloys and sintered at a temperature of 1200 °C. The cavities left in the sintered base part are filled with Cu or Ag-based solder. The disadvantage of this solution is that the resulting materials are very brittle, they lack elasticity and they break under impact. High pressure is usually required for their manufacture, because at a temperature of 1200 °C, diamond obtained without pressure graphitizes.

A composite material is known (US8409691B1) comprising a reinforcement arranged in a matrix of variable stiffness and a connection of reinforcement elements in the matrix of variable stiffness. The composite material comprises a matrix of variable stiffness and a plurality of rigidly interconnected reinforcement elements arranged in a matrix of variable stiffness, the interconnected reinforcement elements reducing the deformation of the composite material in one direction by blocking the movement of the reinforcement elements relative to each other, while allowing deformation in a second direction different from the first direction. This composite material comprises plate-shaped rigid elements connected by a fine connecting strip. The reinforcement elements do not have a shell or base plate on which to attach the elements. The matrix contains a rubber sheet with springs, plates, cables inside and individual protective plates outside. The wear resistance of this material is low due to the lack of a wear-resistant phase. The edges of this material are mobile (deformation is possible), but the surface deformation is limited and it has limited tolerance to multi-cycle (fatigue) deformations.

A solution (US8320727B1) is known which relates to a three-dimensional composite structure and a method of manufacturing the same. This composite structure comprises a regular three-dimensional (3D) microstructure and a second continuous

matrix material. The regular 3D microstructure includes one support lattice elements defined as one self-propagating chain growth polymer waveguides extending along a first direction, second support lattice elements defined as second self-propagating chain growth polymer waveguides extending along a second direction, and third support lattice elements defined as third self-propagating chain growth polymer waveguides extending along a third direction. The first, second, and third support lattice elements are interwoven with each other at lattice nodes to form a first continuous material with a three-dimensional regular microstructure. In addition, the second continuous material has different physical properties compared to the first continuous material and shares an interface with the three-dimensional regular microstructure, wherein the interface is continuous throughout. The SiC-Al composite material can be prepared, for example, by: preparing a polymer microstructure, then carbonizing the polymer microstructure to form a carbon microstructure; The carbon microstructure is coated with silicon carbide (SiC) by chemical vapor deposition (CVD) at high temperatures above 1000 °C in an inert atmosphere. The thickness of the silicon carbide layer is about 20 microns. The microstructure is then heated in an oxidizing environment (air) at temperatures above 600 °C to burn out the carbon microstructure. The result is a microstructure with a micro-supporting lattice, the walls of which are formed by hollow silicon carbide tubes. Aluminum is melted in contact with the SiC microstructure in an inert atmosphere and Al is absorbed and infiltrated into the open spaces of the microstructure. The disadvantage of this solution is the stiff nodes with low fatigue resistance.

A composite material for manufacturing parts using additive manufacturing technology (3D printing) is known (CN107022201A), the composite material contains 45-65 parts of plant fibers, 100-120 parts of plastic waste, 25-44 parts of kaolin, 3-6 parts of fine silica (silica dust), 1-2.5 parts of titanium oxide, 0.7-1.5 parts of binders, 4-10 parts of dispersants (dispersants), 5-12 parts of lubricant, 8-14 parts of reinforcing agent, 15-30 parts of inorganic filler and 0.8-2.2 parts of glass fibers. A raw material for manufacturing parts is provided, which contains glass fibers to increase the strength and wear resistance of the part, but the material cannot withstand multiple large deformations.

The closest technical nature to the invention is composite armor providing ballistic protection against an explosive (EP1363101A1), where the composite armor consists of a ceramic framework formed from several complex ceramic elements, the elements having a cylindrical part and two spherical or flat surfaces.

at the ends. These ceramic elements, made of silicon carbide, silicon nitride, aluminum oxide, etc., are attached to a regular planar honeycomb base layer made of metal tape, fiberglass, Kevlar or plastic. The gaps between the ceramic elements are filled with a binder, which is a synthetic foam. On the back of the structure there is a lower layer of synthetic material, such as Kevlar, which absorbs fragments of the ceramic elements and the projectile. The hard ceramic elements, elastic rubber and elastic fabric hold the entire structure together. Under the action of impacts, the ceramic elements of the composite armor break and move away from the structure.

ESSENCE OF THE INVENTION

The aim of the invention is to reduce the wear of the main components of the material used in tools or machine elements in aggressive conditions with abrasion and dynamic loads (impacts) and to increase the multi-cycle deformation resistance of the surface.

The presented composite material comprises a framework, a hard phase, an elastic material, a binder, wherein the composite material specifically comprises:

- a metal or plastic 3D-printed or other suitable method-made frame, the elements of which are the lower layer of the frame, the walls of the frame, the frame tubes and the joints of the tubes formed in the lower layer of the frame, which allow multiple movement or rotation of the tubes without breaking, which ensures a high tolerance of multi-cycle deformation of the surface; in this case, the tubes are located inside the frame and are inclined with respect to the lower layer of the frame and directed upwards, with the tubes being connected to the lower layer of the frame by joints at the lower end; the frame may be made of metal or plastic:

- the hard phase inside the resulting tubes, or the tubes, are filled with a hard phase to increase wear resistance, which is fixed inside the tubes by means of a binder; wherein the hard phase is technoceramic materials selected from diamond, metal carbides, such as WC, Cr3C2, TiC, Mo2C, SiC, metal nitrides, such as cubic BN, TiN, Si3N4, metal borides, metal oxides, such as Al2O3, stabilized Zr02, Ti02, Cr2O3 or MgO, or carbonitrides; sand, mineral filler or steel particles; the binder may be solder or glue;

- the gaps between the tubes in the frame are filled with elastic material to increase the resistance of the composite material surface to multi-cycle deformations, and

for shock absorption.

The method for producing a composite material includes the following steps: first, a framework is produced using metal or plastic 3D printing or another suitable method, which is formed from the bottom layer of the composite material, walls and tubes, whereby joints connected to the tubes are produced between the tubes and the bottom layer at the lower end of the tubes, which allow the tubes to move or rotate, then the tubes are filled with a hard phase (reinforcing powder) and a binder, which is solder or glue, the framework is soldered or heated in an oven or connected with glue, and finally the parts between the framework tubes are filled with an elastic material, which can be rubber or an elastic polymer. Glue or solder is used as a binder to attach the hard phase to the tubes. In order to accelerate the hardening of the glue, the framework is heated together with the hard phase and the binder in the tubes at a temperature of up to 200 °C. If the binder is solder, the framework is heated together with the hard phase and binder in the tubes at a temperature of 400-1300 °C.

LIST OF DRAWINGS

Figure 1a shows a cross-section of the composite material along line A - A in Figure 1b, Figure 1b shows a top view of the composite material;

Figure 2 illustrates the movement or rotation of composite material tubes;

Figures 3a-3d illustrate the steps of manufacturing the composite material; Figure 4 shows the removal of the top layer of the carcass under abrasive operating conditions.

EXAMPLE OF IMPLEMENTATION OF THE INVENTION

Population growth, urbanization, climate change, infrastructure development in developing countries, depletion of non-renewable resources and the need to increase the share of renewable energy (for example, geothermal energy) increases the demand for tools used for excavation and increases the need to produce biosimilar materials with high wear resistance, permissible surface macrodeformation, high resistance to impacts and fatigue cracking, low density, self-healing ability, cooling, lubrication, etc., intended for abrasive wear conditions, and the need to optimize their production technology (using additive manufacturing technology, i.e. 3D printing or other suitable technology). Possible areas of application of the invention are cutting elements of a penetration harvester

increasing wear resistance (since their replacement is very expensive and dangerous for humans), snowplow edge protection, and even the material of rover wheels (where low dead weight and high wear resistance are very important).

Possible ways to achieve the purpose of the invention are:

- use 3D printing or another suitable method to manufacture the framework, which allows the creation of new composite materials with combined properties;

- combine three basic materials - a hard phase, metal or plastic and an elastic material, adding a binder to them.

The presented composite material includes a framework 1, which is formed by the lower layer of the composite material framework 11, walls 12, tubes 2 and tube joints 3, a hard phase 4 located inside the tubes 2, an elastic material 5 for filling the gaps between the tubes 2 and a binder 6 located inside the tubes 2, with which the hard phase is attached or fixed inside the tubes. The tubes 2 have the possibility of movements or rotations, which is why the load is distributed over a larger surface, reducing damage and allowing larger deformations and higher multi-cyclic deformation tolerance of the working surface.

The composite material includes a hard phase 4, the hardness of which is higher than that of the contacting material, and which is intended to ensure wear resistance, and two materials - an elastic material 5 and a binder 6 - have a lower hardness to improve shock absorption. To ensure greater reliability under multi-cyclic loading conditions, joints 3 of the tubes 2 of the frame 1 made by 3D printing or another suitable method are used. The hard phase 4, the frame 1 and the elastic material 5 are combined, which ensures high wear resistance in abrasive conditions, low density with permissible surface macrodeformations, high resistance to impacts and fatigue. A binder 6 is added, which, together with the elastic material 5, increases impact resistance.

The material of the frame 1 is any metal or plastic that can be produced by printing or other suitable method. In one embodiment, AISI304L or 316L stainless steel powder was chosen, as well as other metals with sufficient strength, above 100 Mpa, and sufficient fatigue strength. In the case of plastic, acrylonitrile-butadiene-styrene (ABS) or polylactic acid (PLA) was used. The hard phase 4 is a mono- or composite material, with a Vickers hardness preferably above 1000HV and a fracture toughness (Kic) above 2 and a strength above

100 MPa. The hard phase material selected is diamond, metal carbides such as WC, Cr3C2, TiC, Mo2C, SiC, metal nitrides such as cubic BN, TiN, Si3N4, metal borides, metal oxides such as Al2O3, stabilized Zr02, Ti02, Cr2O3, MgO or carbonitrides; as well as sand, mineral filler such as basalt, or steel particles. In preferred embodiments, diamond, WC or BN were used.

The elastic material 5 is rubber or some other elastic polymer. In the embodiment, Metaline 685 was used.

The binder 6 used was Ag49MnNi solder, which is suitable for both diamond and WC; for softer reinforcement, epoxy glue or cyanoacrylate glue could be used.

The method for producing a composite material includes the following steps: first, a frame 1 is prepared with a lower layer of the frame 11, walls 12, tubes 2 and tube joints 3 (Figure 3a), the tubes of the frame 1 are filled with a hard phase 4 and a binder 6 (Figure 3b), then the frame 1 is heated (Figure 3c), and after heating, the frame 1 is filled with an elastic material 5 (Step 4, Figure 3d).

The frame 1 is heated together with the hard phase 4 and the binder 6 at a temperature of up to 200 °C to accelerate the curing of the adhesive.

The framework 1 is heated together with the hard phase 4 and the binder 6 at a temperature of 400-1300 °C, if the binder is solder.

Different materials are used in the designs according to the required wear resistance and operating conditions.

Example 1. To ensure higher wear resistance in abrasive (abrasive hardness more than 200HV) conditions, diamond or hard alloy particles are used as the hard phase 4, a metal printed framework 1 with tubes 2 joints 3 and rubber as the elastic material 5. Solder is used to attach the diamond or hard alloy particles to the metal supporting structure.

Example 2. To ensure average wear resistance when the proposed material is in contact with a material with a hardness of less than 200HV, sand or other mineral filler (for example, basalt) or steel particles are used as the hard phase 4, a printed metal or plastic frame 1 with joints 3 of pipes 2 and rubber as the elastic material 5. An adhesive is used to attach the sand, mineral filler or hardened steel to the metal or plastic frame.

Claims (14)

1. A composite material with a frame, the frame (1) of which is formed by the lower layer (11) of the composite material frame and the walls (12) connected thereto, and inside the frame there are tubes (2) inclined with respect to the lower layer of the frame and directed upwards, characterized in that the tubes (2) are connected to the lower layer of the frame at their lower ends by means of joints (3) that enable the tubes to move or rotate, and that the tubes (2) are filled with a hard phase (4) to increase wear resistance, which is fixed inside the tubes by means of a binder (6), and the spaces between the tubes (2) in the frame are filled with an elastic material (5) to increase the tolerance of multi-cycle deformations of the surface of the composite material. 2. A composite material with a framework according to claim 1, characterized in that the hard phase is a technoceramic material selected from diamond, metal carbides such as WC, Cr3C2, TiC, Mo2C, SiC, metal nitrides such as cubic BN, TiN, Si3N4, metal borides, metal oxides such as Al2O3, stabilized ZrO2, TiO2, Cr2O3 or MgO or carbonitrides, sand, mineral filler or steel particles. 3. A composite material with a framework according to claim 2, characterized in that the hard phase material is diamond, WC or cubic BN. 4. A composite material with a framework according to any one of claims 1 to 3, characterized in that the framework (1) is made of metal and the binder (6) is solder or glue. 5. A composite material with a framework according to any one of claims 1 to 3, characterized in that the framework (1) is made of plastic and the binder (6) is an adhesive. 6. A method for producing a composite material with a framework according to any one of claims 1 to 5, comprising the steps of producing a framework from a bottom layer (11) of the composite material, walls (12) and tubes (2) inclined and directed upwards with respect to the bottom layer (11), characterized in that joints (3) connected to the tubes (2) are produced between the tubes (2) and the bottom layer (11) at the lower end of the tubes (2) to enable movement or rotation of the tubes (2), then the tubes (2) of the framework (1) are filled with a hard phase (4) and a binder (6) to fix the hard phase (6) in the tubes (2), then the framework is heated in an oven or with a burner to harden the binder (6), after heating, the spaces between the tubes (2) of the framework (1) are filled with an elastic material (5). 7. The method according to claim 6, characterized in that the frame is made of metal. 8. The method according to claim 6, characterized in that the framework is made of plastic. 9. The method according to claim 6, 7 or 8, characterized in that the framework tubes are filled with a hard phase, which is a technoceramic material selected from diamond, metal carbides, such as WC, Cr3C2, TiC, Mo2C, SiC, metal nitrides, such as cubic BN, TiN, Si3N4, metal borides, metal oxides, such as Al2O3, stabilized ZrO2, TiO2, Cr2O3, MgO or carbonitrides, sand, mineral filler or steel particles. 10. The method according to claim 9, characterized in that diamond, WC or cubic BN is selected as the hard phase material for filling the framework tubes. 11. A method according to any one of claims 6 to 10, characterized in that the elastic material (5) used to fill the gaps between the pipes is rubber or an elastic polymer. 12. The method according to claim 6, characterized in that the binder (6) used for attaching the hard phase to the pipes is an adhesive or solder. 13. The method according to claim 6 or 12, characterized in that the framework together with the hard phase (4) and the binder (6) in the tubes are heated at a temperature of up to 200 °C to accelerate the curing of the adhesive. 14. The method according to claim 6 or 12, characterized in that the framework together with the hard phase (4) and the binder (6) in the tubes is heated at a temperature of 400 - 1300 °C, if the binder is solder.