RU2032524C1 - Sintered composite material for the abrasive and cutting tool - Google Patents

Abstract

FIELD: instrumentation engineering. SUBSTANCE: as a binder the hard-alloy sintered material contains the alloy of one or two elements chosen from the group including: lanthanum, cerium, yttrium, Dutch metal, titanium, zirconium, magnesium, calcium, and one or two elements chosen from the group including: nickel, cobalt, iron, chromium, aluminium, manganese, vanadium, molybdenum at the following ratio of the binder and the hard-alloy component, wt. -% : the metallic binder 3-25, the hard-alloy component - the rest. Cutting and abrasive parts of the tools are made of the material at different combinations of components. After the members are worn down they are detached from the carriers or are placed with them into the hydrogen medium and heated. As a result during the binder hydrogenation it is easily destroyed. The hard-alloy component is easily detached from it. After that the binder and the component are used during the repeated production of the tool. EFFECT: the process of the material regeneration by means of the binder hydrogenation-dehydrogenation results in making the cutting and abrasive tools, such as cutters, milling cutters, drill bits, grinding wheels, without waste products in mass production. 1 tbl

Description

 The invention relates to powder metallurgy, in particular to sintered carbide materials used for the manufacture of abrasive and cutting tools, for example, cutters, milling cutters, drill bits, grinding wheels, etc.

 Known sintered carbide material for abrasive and cutting tools containing a metal binder and carbide component. As a metal binder, it contains copper, tin, titanium hydride and cerium or neodymium additives, and as a carbide component diamond grains (ed. St. USSR N 476327, class C 22 C 1/10, C 22 C 29/00, 1972).

 A disadvantage of the known sintered carbide material is the difficulty of its regeneration after working off an abrasive or cutting tool associated with the chemical dissolution of a metal binder in a mixture of hydrofluoric and nitric acids, extraction of a carbide component from a solution with an irretrievable loss of the metal binder itself.

Closest to the proposed invention in technical essence and the achieved effect is a sintered carbide material for abrasive and cutting tools containing a metal binder intermetallic compound selected from the group including: Ti ₂ Cu, TiCu, Ti ₂ Cu ₃ , TiCu ₃ , Zr ₂ Cu, ZrCu, Zr ₂ Cu ₃ , ZrCu ₃ or their mixture and carbide component (refractory compounds, diamond powder), in the following ratio of components, vol. Metal Binder 5-35 Carbide Component Else
The disadvantages of the known sintered carbide material for abrasive and cutting tools is the complexity of the regeneration of the material and its loss during regeneration.

 The process of regeneration of the known sintered carbide material consists in the chemical dissolution of the metal binder of the material, after the tool has been worked out, followed by separation of the carbide component and its repeated use for preparing the charge of carbide material.

The chemical treatment is carried out in a mixture of nitric and hydrofluoric acid at a temperature of 110-120 ^C in a special acid-resistant equipment, translating to a solution of the metal bundle followed by separation of carbide component, e.g., by filtration or centrifugation. The metal binder passing into the solution represents an irrevocable (up to 30%) loss and, in addition, part of the carbide component (up to 10%) dissolves, which also constitutes an irrevocable material loss.

 Chemical processing of the material is a toxic process that requires special equipment and protective equipment.

 The duration of the regeneration process is from 3 to 5 days (including chemical treatment, separation of the carbide component, drying of the material). (See French patent N 2033432, CL 22 C 29/00, 1970).

 The aim of this invention is to reduce losses during the regeneration of sintered carbide material, simplifying and shortening the duration of the regeneration process.

This goal is achieved in that the sintered carbide material for abrasive and cutting tools containing a metal binder intermetallic compound and carbide component, as an intermetallic compound, it contains an alloy of one or two elements selected from the group including: lanthanum, cerium, yttrium, mishmetal , titanium, zirconium, magnesium, calcium, and one or two elements selected from the group consisting of: nickel, cobalt, iron, chromium, aluminum, manganese, vanadium, molybdenum with a ratio of Comrade defined by equations
for an alloy of one element selected from the group including La, Ce, Y, Mm, Ti, Zr, Mg, Ca and one element selected from the group including Ni, Co, Fe, Cr, Al, Mn, V, Mo
Ax + By x 1
y 2-6.25, where A is an element selected from the group consisting of La, Ce, Y, Mm, Ti, Zr, Mg, Ca;
In one element selected from the group comprising Ni, Co, Fe, Cr, Al, Mn, V, Mo;
x stoichiometric coefficient for element A;
y stoichiometric coefficient for element B;
for an alloy of two elements selected from the group including La, Ce, Y, Mm, Ti, Zr, Mg, Ca and one element selected from the group including Ni, Co, Fe, Cr, Al, Mn, V, Mo
(A _{1-x '} A'x') + By x '0.1-0.9
y 2-6.25 where A is the first element selected from the group comprising La, Ce, Y, Mm, Ti, Zr, Mg, Ca;
A 'is a second element selected from the group consisting of La, Ce, Y, Mm, Zr, Mg, Ca;
In one element selected from the group comprising Ni, Co, Fe, Cr, Al, Mn, V, Mo;
x 'stoichiometric coefficient for element A';
y stoichiometric coefficient for element B;
for an alloy of one element selected from the group including La, Ce, Y, Mm, Ti, Zr, Mg, Ca and two elements selected from the group including Ni, Co, Fe, Cr, Al, Mn, V, Mo
Ax + (B _{5-y '} B' _{y '} ) x 1
y '0.1-4.9, where A is an element selected from the group comprising La, Ce, Y, Mm, Ti, Zr, Mg, Ca;
In the first element selected from the group comprising Ni, Co, Fe, Cr, Al, Mn, V, Mo;
B 'is a second element selected from the group comprising Ni, Co, Fe, Cr, Al, Mn, V, Mo;
x stoichiometric coefficient for element A;
y 'is the stoichiometric coefficient for element B';
for an alloy of two elements selected from the group including La, Ce, Y, Mm, Ti, Zr, Mg, Ca and two elements selected from the group including Ni, Co, Fe, Cr, Al, Mn, V, Mo
(A _{1-x '} A' _x ') + (B _5-y' B ' _y ') x '0.1-0.9
y '0.1-4.9 where A is the first element selected from the group comprising La, Ce, Y, Mm, Ti, Zr, Mg, Ca;
And the second element selected from the group comprising La, Ce, Y, Mm, Ti, Zr, Mg, Ca;
In the first element selected from the group comprising Ni, Co, Fe, Cr, Al, Mn, V, Mo;
B 'is a second element selected from the group consisting of Ni, Co, Fe, Cr, Al, Mn, V, Mo;
x 'stoichiometric coefficient for element A';
y 'is the stoichiometric coefficient for element B'; in the following ratio of metal binder and carbide component, wt. Metal Binder 3-25 Carbide Component Else.

 In the proposed sintered carbide material, the metal binder intermetallic compound has high hardness and strength in combination with high wear resistance. As a carbide component, the material contains carbides of tungsten, titanium, tantalum, complex carbides of tungsten-titanium, tungsten-tantalum, titanium-tantalum, as well as diamond grains.

Regeneration proposed a sintered carbide material is spent hydrogenation instrument at a hydrogen pressure of from 1 to 10 atm at a temperature of from room temperature to 500 ^C. The hydrogenation process is accompanied by hydrogenation metal bond, accompanied by significant volume changes (increase 30%), which lead to the destruction of sintered material into powder (for a mass content of a metal binder of 15-25%) or the formation of cracks in the material. In all cases, during hydrogenation, the material is embrittled, the adhesion strength along the grain boundaries of the carbide component with the binder is significantly reduced.

 The use of the obtained hydrogenated powder for the repeated manufacture of cutting or abrasive elements can be carried out according to the following technological schemes.

 Scheme 1. The hydrogenated powder is loaded into a vacuum oven and heated to a dehydrogenation temperature of the binder, providing the release of hydrogen gas from the powder particles. The dehydrogenation process proceeds at the same temperatures as the hydrogenation of the binder and is accompanied by a decrease in the volume of brittle particles also up to 30% with their cracking into even smaller particles. Further, the dehydrogenated powder can be further crushed using standard mill equipment, sieved and sent to re-molding elements using standard powder technology, pressing and sintering or hot pressing, for example, in an inert gas environment.

 Scheme 2. The hydrogenated powder is additionally crushed in a mill, sieved and formed from it blanks of cutting and abrasive elements, which are then pressed and sintered or subjected to hot sintering in vacuum. In this case, the powder is dehydrogenated and gaseous hydrogen released from it purifies the material from oxides and helps to improve the quality of sintered products (reducing porosity, increasing physical and mechanical characteristics).

 In the above schemes, the losses during the regeneration of the inventive sintered material are associated only with the dust collector at the stage of sifting of the crushed powder and make up no more than 0.5%. Moreover, these losses are captured on the filters and can be returned to the main production.

PRI me R. Intermetallic alloys for a metal binder of sintered carbide material were smelted in an arc furnace with a tungsten non-consumable electrode of the MIFI-9-3 type. The alloy was ground in a vortex mill to a particle size of less than 40 μm and mixed with the powder of the carbide component of tungsten carbide, titanium carbide, tantalum carbide, tungsten carbide-titanium carbide, tungsten carbide-tantalum carbide, and artificial diamond grains. The metal binder intermetallic alloy with a carbide carbide component was pressed in the form of rectangular plates of size 15x15 mm at a specific pressure of 4 tf / cm ² and sintered in vacuum at the temperature of formation of the liquid phase (intermetallic alloy), which was 1500-1700 ^о С for 2 hours Cut-off cutters were made from carbide inserts, which were tested during cutting of steel grade 3.

Metal bonds intermetallic alloy similar to that described above was mixed with diamond grains and pressed into the form of discs 50 mm in diameter and 2 mm thick with a specific pressure of 4 ton / cm ² and sintered at 1,500-1,700 ^{° C,} 2 hours in vacuo.

 Sintered carbide discs were used as an abrasive tool when sharpening tool steel cutters.

 The wear resistance of the cutting and abrasive tools was judged by the degree of wear of the tool during processing per unit time (1 h of work).

 A comparison of the wear resistance of the tool from the proposed sintered carbide material was carried out with the wear resistance of the carbide sintered material of the VK type and with the known sintered carbide material according to the prototype.

 Comparison of wear resistance was carried out with the same amount of metal binder in the material.

 The table shows examples of the compositions of the proposed sintered carbide material and the values of relative wear resistance in comparison with the sintered material type VK and known (prototype).

 From the data given in the table it follows that the proposed sintered carbide material for abrasive and cutting tools in terms of their operational characteristics (cutting and abrasive properties) is at the level of the operational properties of industrial carbide material (VK) and the known carbide material of the prototype.

The regeneration of the spent tool with the claimed sintered carbide material was carried out by hydrogenation of the material in a hydrogen atmosphere at temperatures up to 500 ^C and the hydrogen pressure to 10 atm. within 3-4 hours. During the hydrogenation, hydrogen binder of the metal binder occurs with an increase in its volume up to 30%. Moreover, depending on the composition of the binder, hydrogen binder occurs both at room and at elevated temperature, both at a pressure of 1 atm and at elevated pressure up to 10 atm. Under moderate conditions (T 500 ^° C, P _H2 10 atm), all ligament compounds undergo hydrogenation.

 After hydrogenation, the proposed sintered carbide material is partially destroyed, but in all cases it loses bond strength along the boundaries of the refractory component and is easily crushed into powder. The hydrogenated material was crushed in a vortex mill for 0.5 h to a particle size of less than 56 μm and reused to form sintered carbide material by pressing and sintering or hot pressing in vacuum. During sintering or hot pressing in vacuum, the metal binder is dehydrogenated and acquires its original properties.

 A cutting and abrasive tool made from reclaimed material has the same performance characteristics as a tool made using non-regenerated (source) material. Thus, the duration of the regeneration process of the claimed sintered carbide material is composed of hydrogenation of the spent material (up to 4 hours) and grinding it into powder (up to 1 s with sieving) and up to 5 hours. Moreover, the amount of simultaneously regenerated material is limited only by power ( dimensions) of equipment and can reach several tons. Large volumes are especially beneficial when using a tool with mechanical fastening of cutting elements from the proposed material. This allows you to pre-disconnect the cutting elements from the holders and load them in large quantities in a hydrogen furnace. For the known sintered carbide material, the regeneration duration is 3 days.

In addition, losses during the regeneration of the known material amount to ≈30% of the metal binder and ≈10% of the refractory component. During the regeneration of the inventive sintered carbide material, losses are associated only with possible dust extraction and do not exceed 0.5%
The use of standard hydrogen furnaces instead of complex and environmentally harmful chemical processes with irretrievable losses of all components allows us to obtain significant savings in resources and energy in the preparation and processing of the inventive carbide material for metalworking, mining, oil and gas and other technical fields. The process of material regeneration by hydrogenation makes it quite simple to carry out the technological cycle of waste-free production of carbide cutting and abrasive tools on a massive scale.

Claims (1)

 SINTERED COMPOSITE MATERIAL FOR ABRASIVE AND CUTTING TOOLS, containing a solid component and an intermetallic binder, characterized in that, as an intermetallic binder, it contains an alloy of one or two elements selected from the first group including lanthanum, cerium, yttrium, mishmetal, titanium, mishmetal, titanium , magnesium, calcium and one or two elements selected from the second group, including nickel, cobalt, iron, chromium, aluminum, manganese, vanadium, molybdenum, in the following ratio of the components of the binder: for alloy Islands of any one element selected from the first group and any one element selected from the second group, the stoichiometric coefficients are respectively 1 and 2, 6.25; for an alloy of any two elements selected from the first group and any one element selected from the second group, stoichiometric coefficients are respectively 0.9 0.1 - for the first element from the first group, 0.1 0.9 for the second element from the first group, 2 6.25 for an element from the second group; for an alloy from any one element selected from the first group and any two elements selected from the second group, stoichiometric coefficients are 0.1 for an element from the first group, 4.9 0.1 for the first element from the second group, 0.1 4.9 for the second element from the second group; for an alloy of any two elements selected from the first group and any two elements selected from the second group, stoichiometric coefficients are 0.9 0.1 for the first element from the first group, 0.1 0.9 for the second element from the first group 4.9 0.1 for the first element from the second group, 0.1 4.9 for the second element from the second group, with the following ratio in the material of the solid component and the intermetillide binder, wt. Intermetallic Binder 3 25
Solid component Else.

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