CN104628385A - Boric nano titanium carbonitride solid solution powder and preparation method thereof - Google Patents

Abstract

The invention discloses a boron-containing nano-titanium carbonitride solid solution powder and a preparation method thereof, wherein B is 0.1-5%; C is 5-14%; N is 5-15%; M is 4-38%; and the balance is Ti ; The M is at least one of W, Mo, V, Cr, Ta, Nb. The preparation steps include preparing the prepared raw materials into a mixed solution and drying to obtain a precursor mixed powder; calcining the precursor mixed powder; carbothermal reduction and solid solution of the calcined powder material; and purifying the synthesized powder material. In addition to preparing boron-containing titanium carbonitride cermet blocks, the invention can also be used as spraying powder to prepare wear-resistant coatings, and can also be used as reinforcing phase powder to prepare particle-reinforced metal-based composite materials. The invention greatly reduces the reaction temperature and shortens the reaction time, and the prepared boron-containing titanium carbonitride solid solution powder has an average particle diameter of <100 nm, uniform distribution of component elements, and less impurity content.

Description

Boron-containing nano-titanium carbonitride solid solution powder and preparation method thereof

technical field

The invention relates to a method for preparing boron-containing nano-titanium carbonitride solid solution powder, and belongs to the technical field of nano-ceramic powder preparation.

Background technique

Cutting is the dominant processing method in manufacturing technology. In recent years, the depletion of tungsten resources has forced countries all over the world to actively develop alternative materials for WC-based cemented carbide tools. In the earth's crust, the reserve of Ti is 77 times that of W, and Ti(C, N)-based cermets have a series of advantages such as wear resistance, corrosion resistance, and high temperature resistance, which make them the main substitute for WC-based cemented carbide. one of the materials. The literature (Chinese invention patent, CN200810031010.6) reported that the addition of boron can significantly improve the high-temperature cutting performance of Ti(C, N)-based cermets. The preparation method of the cermet adopts the traditional powder metallurgy method, that is, the single-component powder containing boron and other single-component powders, such as Ti(C,N) or TiC or TiN powder, Ni or Co powder, the second type of carbonization One or more powders of materials (such as WC, Mo ₂ C, VC, Cr ₃ C ₂ , TaC, NbC, etc.) are added to a ball mill to grind and mix, then pressed to form, and then sintered to form the desired shape cermet blocks. Since it is difficult to uniformly mix boron-containing single component powder (such as elemental boron) with other raw material powders by ordinary ball milling, it will inevitably lead to its segregation in the cermet structure, so the boron-containing titanium carbonitride base prepared by the above method Coarse boride phases are easily produced in cermet bulk materials, resulting in unstable performance. In addition, the second type of carbide (such as WC, Mo ₂ C, VC, Cr ₃ C ₂ , TaC, NbC, etc.), which is one of the essential components of Ti(C, N)-based cermets, is usually prepared as a single powder Form addition, which will also cause segregation in the cermet structure due to uneven mixing by ball milling. Therefore, preparing all multi-component hard phase powders except Ni or Co binder phase powders into boron-containing titanium carbonitride solid solution powders with a single phase composition can fundamentally solve the problem of B elements and the second type. The technical problem of segregation of carbide elements (such as W, Mo, etc.) in the final structure of the material due to uneven mixing by ball milling.

The literature (Chinese invention patent, CN201110284340.8) reports a preparation method of titanium borocarbonitride (Ti(B,C,N)) ceramic powder. This method uses metal Ti powder as a raw material, and the raw material cost is high; and due to technical limitations, the synthesized powder cannot reach the nanometer size range, and only micron powder can be synthesized. Another technical defect of this method is that the synthetic powder contains high concentrations of impurity elements such as F, O and Si, and the upper limit of the total atomic content of impurity elements is close to 5%. There is a big gap between this and the industrial production of high-performance cermet bulk materials, which generally require the content of impurity elements to be less than 1%, and it is difficult to meet industrial needs. In addition, the Ti(B,C,N) powder does not involve solid solution of the second type of carbide elements (such as W, Mo, V, etc.).

Contents of the invention

For the above-mentioned deficiencies in the prior art, the purpose of the present invention is to provide a boron-containing nano-titanium carbonitride solid solution powder and a preparation method thereof, so as to increase the types of boron-containing titanium carbonitride cermet materials, and solve the problem of B The segregation of elements and the second type of carbide elements (such as W, Mo, etc.) in titanium carbonitride-based cermet materials. In addition, the boron-containing titanium carbonitride solid solution powder provided by the present invention has the characteristics of a high-purity nano-powder with a single phase component, which can meet the requirements for the preparation of high-performance nanometer or ultrafine titanium carbonitride cermet blocks, and can also Prepare particle-reinforced metal matrix composites and wear-resistant coatings as nano-reinforced phase powders.

Technical scheme of the present invention is realized like this:

Boron-containing nano-titanium carbonitride solid solution powder is characterized in that: the components contained in it and the weight percentages of each component are: B 0.1-5%; C 5-14%; N 5-15%; M 4- 38%; the balance is Ti; the M is at least one of W, Mo, V, Cr, Ta, Nb.

The expression of the nano-titanium carbonitride solid solution powder is (Ti,M)(B,C,N), which has the characteristics of a single phase composition, that is, (Ti,M)(B,C,N) has the only sodium chloride type The face-centered cubic lattice structure, in which the element atoms represented by Ti and M occupy the lattice positions of sodium atoms, and the element atoms of B, C and N occupy the lattice positions of chlorine atoms.

A method for preparing boron-containing nano-titanium carbonitride solid solution powder, the preparation steps are as follows,

(1) Ingredients, according to the aforementioned components and amounts,

The raw material of component Ti is metatitanic acid;

The raw material of component C is glucose;

The raw material of component B is boric acid or ammonium pentaborate;

The raw material of component M is a soluble salt of at least one metal element in W, Mo, V, Cr, Ta, Nb;

(2) Prepare the mixed solution and dry it

Dissolving the raw materials prepared in step (1) with distilled water to prepare a mixed solution, the amount of distilled water is enough to ensure that all component raw materials can be fully mixed; then the mixed solution is dried at 60~120°C for 1~5h to obtain Precursor mixed powder;

(3) Powder Calcination

Calcining the precursor mixed powder prepared in step (2) under the protection of Ar gas at 400-500°C for at least 0.5h to obtain a mixture of elements mixed uniformly at the molecular level;

(4) Carbothermal reduction, solid solution

Put _{the calcined powder material in step (3) into a vacuum carbon tube furnace, and then feed N 2 into} the reaction furnace. The N content is limited, at 1150-1400 ° C for at least 0.5-2 hours for carbothermal reduction and solid solution, to obtain boron-containing titanium carbonitride solid solution powder with an average particle size of <100 nm;

(5) Finally, put the powder synthesized in step (4) in a tube furnace and purify at 850-950°C for 0.5-1h under the protection of H ₂ gas, and finally obtain boron-containing nanoparticles with a total content of impurity element atoms less than 1%. Titanium carbonitride solid solution powder.

The raw material of component M is a soluble salt of two or more metal elements in W, Mo, V, Cr, Ta, Nb.

Compared with the prior art, the present invention has the following advantages:

1. The present invention provides a boron-containing nano-titanium carbonitride solid solution powder with a single phase composition. In addition to preparing boron-containing titanium carbonitride cermet blocks, it can also be used as a spray powder to prepare wear-resistant coatings. Particle-reinforced metal matrix composites were prepared as reinforcement phase powder.

2. The present invention uses metal oxide precursors, boron oxide precursors, and glucose as raw materials, which are rich in sources, low in price, and cost-saving.

3. The present invention greatly reduces the reaction temperature and shortens the reaction time from two technical levels at the same time: (1) Use precursor raw materials to achieve uniform mixing of elements in the reactant system at the molecular level; (2) Use vacuum carbonization to reduce reaction products The partial pressure of the medium gas is conducive to the progress of the carbothermal reaction; finally, the boron-containing nano-titanium carbonitride solid solution powder with a single phase composition can be prepared at a temperature of 1150-1400 ° C for 0.5-2 hours.

4. The boron-containing titanium carbonitride solid solution powder prepared by the present invention has an average particle size of <100 nm, uniform distribution of component elements, and less impurity content.

5. The process of the method of the present invention is simple, and the carbothermal reduction and solid solution processes of all components are completed through one carbonization operation. The equipment used is conventional equipment, which is easy to operate and suitable for industrial production.

Description of drawings

Fig. 1 - XRD pattern of (Ti, 20W, 10Mo, 0.5V) (B _0.1 , C _0.45 , N _0.45 ) powder prepared in Example 3.

Fig. 2 - 200,000 magnification field emission scanning electron microscope image of (Ti, 30Mo, 7Ta, 5Cr, 3Nb) (B _0.3 , C _0.35 , N _0.35 ) powder prepared in Example 4.

.

Detailed ways

The boron-containing nano-titanium carbonitride solid solution powder of the present invention has an expression of (Ti, M)(B, C, N). The components contained therein and the weight percentages of each component are: B 0.1-5%, C 5-14%, N 5-15%, M 4-38%, the balance is Ti, and the M is W, Mo , V, Cr, Ta, Nb at least one.

The nano-titanium carbonitride solid solution powder has the characteristics of a single phase composition. The so-called single-phase composition means that (Ti, M) (B, C, N) has a unique face-centered cubic lattice structure of sodium chloride type, in which the element atoms represented by Ti and M occupy the lattice positions of sodium atoms, B, C and N element atoms occupy the lattice positions of chlorine atoms.

The above-mentioned nano-titanium carbonitride solid solution powder has an average particle diameter of <100nm.

The above-mentioned nano-titanium carbonitride solid solution powder has a total content of impurity element atoms less than 1%.

The preparation method of boron-containing nano titanium carbonitride solid solution powder of the present invention, its preparation steps are:

(1) Ingredients

The raw material of component Ti is metatitanic acid;

The raw material of component C is glucose;

The raw material of component B is boric acid or ammonium pentaborate;

The raw material of component M is a soluble salt of at least one metal element in W, Mo, V, Cr, Ta, Nb;

(2) Preparation of mixed solution and drying

Dissolve the raw materials prepared in step (1) with distilled water to prepare a mixed solution. The amount of distilled water is enough to ensure that all component raw materials can be fully mixed. Then dry the above precursor solution (placed in a blast drying oven) at 60-120°C for 1-5 hours to obtain a precursor mixed powder;

(3) Powder Calcination

The precursor mixed powder prepared in step (2) was calcined at 400-500°C for at least 0.5h under the protection of Ar gas to obtain an "oxide-carbon" mixture in which each element was uniformly mixed at the molecular level; "oxide-carbon "Mixture" is a mixture of at least one metal oxide, titanium oxide, boron oxide and carbon in "W, Mo, V, Cr, Ta, Nb".

(4) Carbothermal reduction, solid solution

Put _{the calcined powder material in step (3) into a vacuum carbon tube furnace, and then feed N 2 into} the reaction furnace. The N content is limited (0.001~0.06 MPa), and the temperature is kept at 1150~1400°C for at least 0.5~2h for carbothermal reduction and solid solution to obtain boron-containing titanium carbonitride solid solution powder with an average particle size of <100 nm.

(5) Finally, put the powder synthesized in step (4) in a tube furnace and purify at 850-950°C for 0.5-1h under the protection of H ₂ gas, and finally obtain boron-containing nanoparticles with a total content of impurity element atoms less than 1%. Titanium carbonitride solid solution powder.

The preparation method of the present invention will be further described through four examples below.

Example 1

Dissolve 47.65g of metatitanic acid, 1.75g of ammonium metatungstate, 1.52g of boric acid, and 49.08g of glucose in 300ml of distilled water, and stir evenly to obtain a precursor solution. Drying under conditions for 5 hours to obtain the precursor mixed powder; the precursor mixed powder was placed in a tube furnace and calcined at 500°C for 0.5 hours under the protection of Ar gas to obtain the "oxide-carbon oxide" with uniform mixing of elements at the molecular level. "mixture; put the "oxide-carbon" mixture into a vacuum carbon tube furnace, then pass _N2 to 0.01MPa into the reaction furnace, and keep it at 1400°C for 0.5h for carbothermal reduction and solid solution to obtain the average particle size Solid solution powder with a diameter of <100nm; finally, put the solid solution powder in a tube furnace and purify it at 850°C for 1h under the protection of H ₂ gas, and finally obtain a nanometer (Ti,5W )(B _0.05 , C _0.65 , N _0.3 ) powder, where 5 in 5W represents 5wt.% of the total atomic percentage content of (Ti+W) element W, and 0.05 in B _0.05 represents that element B accounts for (B+ 5% of the total atomic percentage content of C+N), that is, the molar content, 0.65 in C _0.65 represents that C element accounts for 65% of the total atomic percentage content of (B+C+N), and 0.3 in N _0.3 represents N element accounts for 30% of the total atomic percentage content of (B+C+N).

In the (Ti,5W)(B _0.05 ,C _0.65 ,N _0.3 ) powder prepared in this example, the weight percentages of each component are: Ti 75.75%, W 4.13%, B 0.87%, C 12.51%, N 6.74 %.

Example 2

Dissolve 43.16g of metatitanic acid, 9.84g of ammonium dimolybdate, 2.12g of tantalum fluoride, 0.31g of boric acid, and 44.57g of glucose in 300ml of distilled water, and stir evenly to obtain a precursor solution, and place the solution in air-dried In the box, dry at 80°C for 4h to obtain the precursor mixed powder; place the precursor mixed powder in a tube furnace and calcinate at 500°C for 0.5h under the protection of Ar gas to obtain a homogeneous mixture of elements at the molecular level The "oxide-carbon"mixture; put the "oxide-carbon" mixture into a vacuum carbon tube furnace, and then pass N ₂ to 0.06MPa into the reaction furnace, and keep it at 1300°C for 1h to carry out carbothermal reduction and solidification. Dissolved to obtain a solid solution powder with an average particle size of <100nm; finally, the solid solution powder was placed in a tube furnace and purified at 850°C for 1h under the protection of _H2 gas, and finally obtained a solid solution powder with a total content of impurity element atoms less than 1% and a single phase composition Nano (Ti, 20Mo, 5Ta) (B _0.01 , C _0.3 , N _0.69 ) powder.

In the (Ti,20Mo,5Ta)(B _0.01 ,C _0.3 ,N _0.69 ) powder prepared in this example, the weight percentages of each component are: Ti 60.45%, Mo 16.12%, Ta 4.02%, B 0.15%, C 5.23%, N 14.03%.

Example 3

Dissolve 38.86g of metatitanic acid, 7.52g of ammonium metatungstate, 4.85g of ammonium dimolybdate, 0.56g of ammonium metavanadate, 2.83g of boric acid, and 45.38g of glucose in 300ml of distilled water, and stir evenly to obtain a precursor solution , the solution was placed in a blast drying oven, and dried at 100°C for 2.5h to obtain a precursor mixed powder; the precursor mixed powder was placed in a tube furnace and calcined at 400°C for 1h under the protection of Ar gas to obtain The "oxide-carbon" mixture in which each element is uniformly mixed at the molecular level; the "oxide-carbon" mixture is placed in a vacuum carbon tube furnace, and then N ₂ to 0.03MPa is passed into the reaction furnace, at 1200°C Insulate for 1.5h for carbothermal reduction and solid solution to obtain a solid solution powder with an average particle size of <100nm; finally, place the solid solution powder in a tube furnace and purify it at 950°C for 0.5h under the protection of _H2 gas to finally obtain impurity element atoms Nano (Ti, 20W, 10Mo, 0.5V) (B _0.1 , C _0.45 , N _0.45 ) powder with a total content of less than 1% and a single phase composition.

In the (Ti, 20W, 10Mo, 0.5V) (B _0.1 , C _0.45 , N _0.45 ) powder prepared in this example, the weight percentages of each component are: Ti 57.25%, W 16.48%, Mo 8.24%, V 0.41%, B 1.49%, C 7.44%, N 8.69%. Fig. 1 is the XRD spectrum of the (Ti, 20W, 10Mo, 0.5V) (B _0.1 , C _0.45 , N _0.45 ) powder prepared in Example 3.

Example 4

Dissolve 28.29g of metatitanic acid, 13.37g of ammonium dimolybdate, 2.71g of tantalum fluoride, 3.05g of ammonium dichromate, 1.48g of niobium oxalate, 6.69g of ammonium pentaborate, and 44.41g of glucose in 300ml of distilled water, and stir Prepare the precursor solution uniformly, place the solution in a blast drying oven, and dry it at 120°C for 1 hour to obtain a precursor mixed powder; place the precursor mixed powder in a tube furnace under the protection of Ar gas at 400 ℃ calcination for 1 hour to obtain an "oxide-carbon" mixture in which each element is uniformly mixed at the molecular level; put the "oxide-carbon" mixture into a vacuum carbon tube furnace, and then pass N ₂ to 0.015 MPa, heat at 1150°C for 2h for carbothermal reduction and solid solution to obtain a solid solution powder with an average particle size of <100nm; finally put the solid solution powder in a tube furnace and purify it at 950°C for 0.5h under the protection of _H2 gas, and finally A nanometer (Ti, 30Mo, 7Ta, 5Cr, 3Nb) (B _0.3 , C _0.35 , N _0.35 ) powder with a total content of impurity element atoms less than 1% and a single phase composition was obtained.

In the (Ti, 30Mo, 7Ta, 5Cr, 3Nb) (B _0.3 , C _0.35 , N _0.35 ) powder prepared in this example, the weight percentages of each component are: Ti 45.76%, Mo 24.96%, Ta 5.88%, Cr 4.16%, Nb 2.52%, B 4.39%, C 5.69%, N 6.64%. Fig. 2 is a 200,000 magnification field emission scanning electron microscope image of the (Ti, 30Mo, 7Ta, 5Cr, 3Nb) (B _0.3 , C _0.35 , N _0.35 ) powder prepared in Example 4.

The above-mentioned embodiments of the present invention are only examples for illustrating the present invention, rather than limiting the implementation of the present invention. For those of ordinary skill in the art, other variations and modifications in various forms can be made on the basis of the above description. All the implementation manners cannot be exhaustively listed here. All obvious changes or changes derived from the technical solutions of the present invention are still within the protection scope of the present invention.

Claims (4)

1. the nano-carbon titanium nitride solid-solution powder of boracic, is characterized in that: the weight percent of component contained by it and each component is: B 0.1 ~ 5%; C 5 ~ 14%; N 5 ~ 15%; M 4 ~ 38%; Surplus is Ti; Described M is at least one in W, Mo, V, Cr, Ta, Nb.

2. the nano-carbon titanium nitride solid-solution powder of boracic according to claim 1, it is characterized in that: this nano-carbon titanium nitride solid-solution powder expression formula is (Ti, M) (B, C, N), there is single-phase composition characteristics, i.e. (Ti, M) (B, C, N) have the face-centered cubic lattice structure of unique NaCl type, the Elements Atom wherein representated by Ti, M occupies the lattice position of sodium atom, and B, C and N element atom occupy the lattice position of chlorine atom.

3. the nano-carbon titanium nitride solid-solution powder preparation method of boracic, is characterized in that: its preparation process is as follows,

(1) prepare burden, prepare burden by component described in claim 1 and amount,

The raw material of component Ti is metatitanic acid;

The raw material of component C is glucose;

The raw material of B component is boric acid or ammonium pentaborate;

The raw material of component M is the soluble salt of at least one metallic element in W, Mo, V, Cr, Ta, Nb;

(2) mixing solutions is prepared also dry

Raw material distilled water step (1) be equipped with dissolves and is mixed with mixing solutions, and the amount of distilled water is to guarantee that all components raw material can fully mix; Then by described mixing solutions dry 1 ~ 5h under 60 ~ 120 DEG C of conditions, presoma mixed powder is obtained;

(3) powder calcining

Presoma mixed powder prepared by step (2) is calcined at least 0.5h in 400 ~ 500 DEG C under Ar gas shielded, obtains the mixture that each element mixes in molecule rank;

(4) carbothermic reduction, solid solution

Powder materials after step (3) being calcined puts into vacuum carbon tube furnace, then in Reaktionsofen, passes into N ₂, the N passed into ₂the N content measured in the component of the titanium carbonitride solid-solution powder to meet boracic is limited, within at least 0.5 ~ 2h hour, carry out carbothermic reduction, solid solution 1150 ~ 1400 DEG C of insulations, obtain the titanium carbonitride solid-solution powder of median size <100 nm boracic;

(5) finally the powder materials that step (4) is synthesized is placed in tube furnace in H ₂at 850 ~ 950 DEG C of purifying 0.5 ~ 1h under gas shielded, the final nano-carbon titanium nitride solid-solution powder obtaining impurity element atom total content and be less than the boracic of 1%.

4. the nano-carbon titanium nitride solid-solution powder preparation method of boracic according to claim 3, is characterized in that: the raw material of component M is the soluble salt of in W, Mo, V, Cr, Ta, Nb two kinds or two or more metallic element.