CN102432297A

CN102432297A - Titanium carbonitride boron (Ti (B, C, N)) ceramic powder material and preparation method thereof

Info

Publication number: CN102432297A
Application number: CN2011102843408A
Authority: CN
Inventors: 胡建东; 董鲜峰; 曹勇
Original assignee: Jilin University
Current assignee: Jilin University
Priority date: 2011-09-23
Filing date: 2011-09-23
Publication date: 2012-05-02
Anticipated expiration: 2031-09-23
Also published as: CN102432297B

Abstract

The invention relates to a boron titanium carbonitride (Ti (B, C, N)) ceramic powder material and a preparation method thereof, wherein the Ti (B, C, N) ceramic powder material is a compound formed by combining Ti, B, C and N elements, and the atomic percent of B is 0.02-96 at%; the atomic percentage of C is 0.04-50 at%; the atomic percentage of N is 0.02-82 at%; the balance being the atomic percent of Ti. The compound contains small amount of impurity elements F, O and Si, etc. and the total atom content of the impurity elements is less than 5%. The preparation method of the material comprises the following steps: pressing a green compact; preparing a solid boronizing agent and a solid carburizing agent; preparing a solid boron-carbon mixed permeating agent; packing the pressed green compacts into boxes; sintering and pulverizing in ammonia decomposition atmosphere or air. The compound is prepared by reacting Ti powder with the active atoms [ B ] and [ C ] generated by the solid boron-carbon mixed permeating agent and the N atoms in the ammonia decomposition atmosphere to generate the Ti multi-component compound.

Description

A kind of boron titanium carbonitride (Ti (B, C, N)) ceramic powder material and preparation method thereof

Technical field

(Ti (B, C, N)) ceramic powder material and preparation method thereof belongs to function or technical ceramics field of materials to the present invention relates to the boron titanium carbonitride.

Background technology

Pottery is the compound that is formed by metallic element and non-metallic element.Usually claim that the oxygen and the compound of metal formation are oxide ceramics, wherein common have an Al ₂O ₃And CeO ₂Deng.Also having one type of pottery is the pottery that is formed by metal and nonoxygen element, and common have SiC, SiN, a MoSi ₂, TiN and TiC etc., they are summed up as non-oxide ceramics.This type pottery is in high temperature resistant, corrosion-resistant, wear-resistant, electroconductibility, optical property and mechanical properties exhibits excellent, and for example the intensity of silicon nitride SiN can reach 700MP; Hardness 1800Kg/mm ²BaTiO ₃Can produce electric current under pressure, be called piezoelectric ceramics.The TiC pottery can produce ir radiation.Usually claim that this type pottery is function ceramics or technical ceramics.

Ti is a magnesium-yttrium-transition metal, and it forms some compound with non-metallic element boron, carbon and the nitrogen element of the periodic table of elements in second cycle, and TiC, TiN and TiO are arranged; They are NaCl profile heart cubic crystal structure, and lattice parameter is respectively 0.423nm, 0.4238nm; 0.415&nm, very approaching.TiC can be used for preparing matrix material, foamed ceramics and preparation coating, is used for diamond coatings, anti-tritium coating and contact material coating.TiN is mainly used in the preparation ganoine thin film, increases the work-ing life of cutting tool and mould, also can be used for structured materials such as high-intensity cermet tool, vapor-injection propeller and rocket.In addition, titanium nitride has lower frictional coefficient, can be used as high temperature lubricant.The titanium nitride alloy can demonstrate excellent effect as bearing and wear ring.Titanium nitride has higher electroconductibility, can be used as the electrode of fused salt electrolysis and puts materials such as contact, sheet resistance.Pure TiO has golden yellow and is mainly used in imitation gold copper-base alloy.Ti (C, N) be in TiC solid solution N element or in TiN, dissolved in the formed a kind of binary compound of C, and Ti (B N) is the multi-element compounds that contains B and N element, is keeping original face-centred cubic structure, but its performance has obtained obvious optimization.(B, C N) can be regarded as that (C has added the multi-element compounds that the B element forms in N), and (B N) has better properties, especially aspect self lubricity than Ti at Ti to Ti.The above blocking compound TiC, TiN and TiO and multi-element compounds Ti (C, N), Ti (B, N) and Ti (B, C; N) in, TiC, TiN and TiO and Ti (C N) has powdered material, and existing Ti (B; N) and Ti (N) material all is to exist with thin-film material, does not have powder body material for B, C; Promptly at home and abroad market and laboratory can not find powder Ti (B, N) and Ti (B, C, N) material.

The compound method of TiC powder has carbothermic method, direct carborization, chemical vapour deposition, self-propagating high-temperature synthesis method (SHS) and reaction ball milling method etc.(C, N) compound method of powder has Ti metal powder or TiH for TiN and Ti ₂Direct nitridation method, TiO ₂Carbothermal reduction-nitridation method, self propagating high temperature synthesis method, microwave carbothermic method and mechanical alloying method etc.Normally adopt physical vapor deposition (PVD) and chemical vapor deposition (CVD) method prepare Ti (B, N) and Ti (B, C, N) thin-film material, technology is very complicated.(C N) has powder-product for TiC, TiN and Ti.And existing pure contain B multi-element compounds Ti (B, N) and Ti (B, C N) only exist with form of film, do not have powder-product.

Summary of the invention

The objective of the invention is to the above-mentioned shortcoming that the customer service prior art exists, provide a kind of boron titanium carbonitride (Ti (B, C, N)) ceramic powder material and preparation method thereof, the method for employing is simple, reliable, cost is low and easy realization, material property is good.

Above-mentioned purpose of the present invention realizes through following technical scheme:

A kind of boron titanium carbonitride (Ti (B, C, N)) ceramic powder material, said ceramic powder material is that wherein the atomic percent of B is 0.02～96at% by B, C and N element and the elementary composition compound of Ti; The atomic percent of C is 0.04～50at%; The atomic percent of N is 0.02～82at%; Surplus is the atomic percent of Ti.

Said chemicals are with following chemical formula Ti (B _x, C _y, N _z) expression, wherein x, y and z represent the chemical composition of B, C and N element respectively.

(N) ceramic powder for the pressed powder state, has crystalline structure to said Ti when being lower than melting temperature for B, C.

Said crystalline structure is B, C and the sosoloid of N element in the Ti metal, and atom is arranged by sodium-chlor profile heart cubic lattice mode, and wherein titanium atom occupies the position suitable with sodium atom, and B, C and N element occupy the position suitable with the chlorine atom.

Said B, C and N element be with chemical combination or solid solution form be stored in Ti (B, C, N) among.

Concrete steps are following:

Step 1, the compacting pressed compact

Suppress pressed compact with pressing machine: pack the Ti powder in the mould into earlier, powder is exerted pressure process pressed compact then, density is 50%～90% of theoretical density;

Step 2, the preparation pack boronizing medium

The prescription of pack boronizing medium is: 5～15%B-Fe (ferro-boron), 2～8% gacs, 5～10% charcoals, 2～%6KBF ₄, SiC surplus %;

Step 3, the preparation solid carburizer

The prescription of solid carburizer is: 85～95% charcoals and 15～5% yellow soda ash

Step 4 is with pack boronizing medium and solid carburizer preparation solid boron carbon mixing penetration enhancer

Prepare solid boron carbon mixing penetration enhancer with two and three pack boronizing mediums that are mixed with and solid carburizer set by step, prescription is: the ratio of pack boronizing medium and solid carburizer is 4～9: 1;

Step 5, pressed compact dress box

Be ready to magazine, earlier with four solid boron carbon the mixings penetration enhancer shop fixtures that prepare set by step, be placed on the centre to pressed compact, reach top filling solid boron carbon mixing penetration enhancer all around, the solid penetration enhancer is a particulate state; Or with the Ti powder without compacting replace the Ti pressed compact as raw material directly by the magazine of packing into upper type;

Step 6, sintering

Be placed on sintering in the resistance furnace to the magazine that installs, resistance furnace has protective atmosphere, and protective atmosphere is the gas that liquid ammonia decomposes; Its composition is: 70%N2 and 30%H2 gas; Or without the direct sintering in air of protective atmosphere, sintering temperature is 700～1200C, and the time is 2～6 hours;

Step 7, powder process

Magazine is taken out in stove, treat that magazine fully cools off after, take out the agglomerating pressed compact high purity Ti (B, C, N) ceramic powder that after slightly rolling, have just obtained to have face-centred cubic structure.

Pack boronizing medium, solid carburizer and protective atmosphere can use simultaneously.

Produce activity [B] and [C] atom simultaneously at the above solid boron of 700C carbon mixing penetration enhancer; Protective atmosphere or air produce active [N] atom, and these three kinds of active atomics and Ti chemical reaction take place generate compound.

Technique effect of the present invention:

The ceramic powder of the present invention's preparation is different from existing TiC and TiN powder-product, also is different from Ti (C, N) powder-product.Also be different from simultaneously existing quadrature TiB precipitated phase, but Ti (B, C, N) powder-product, it is a kind of new Ti (B, C, N) ceramic powder with face-centred cubic structure.In searching document, do not appear in the newspapers, do not see analogous products in market yet.The method that adopts is simple, reliable, cost is low and easy realization, and material property is good.

Description of drawings

Fig. 1 Ti (B, C, N) powder SEM photo.

(N) the X-ray diagram of powder meets face-centred cubic structure to Fig. 2 Ti for B, C.

Fig. 3 Ti (B, C, N) powdered preparation principle and device.

Fig. 4 Ti (B, C, N) powder photo.

That installs among Fig. 3 constitutes: 1. inlet pipe; 2. decomposed ammonia body; 3. non-covered container; 4. pressed compact; 5. top cover; 6. active [B] [C] [N] atom; 7. [B]+[C]+[N]+H ₂8. escape pipe; 9. solid boron carbon compound (mixing) penetration enhancer; 10. boron carbon oozes jar;

Embodiment

Further specify the boron titanium carbonitride of the present invention (particular content of Ti (B, C, N)) ceramic powder material and preparation method thereof below in conjunction with instance.

Boron titanium carbonitride of the present invention (purpose of Ti (B, C, N)) ceramic powder material and preparation method thereof be propose with more than different boron titanium carbonitride (Ti (B, C, N)) ceramic powder material and preparation method thereof.(N) ceramic powder material is pure powder body material to this Ti for B, C; To the um level, Fig. 1 (SEM photo) shows nano level Ti (B, C to particle size distribution from nano level; N) powder particle only contains the small amount of impurities element, and the total impurities constituent content is less than 5%; It has the sodium-chlor face-centered cubic crystal structure, and it is pure face-centered cubic crystal structure material (as shown in Figure 2) that its X-ray (XRD) detects.(B, C are that chemical formula can be expressed as Ti (B by Ti element and B, C, the elementary composition compound of N N) to Ti _x, C _y, N _z).The atomic percent of B is 0.02～96at%; The atomic percent of C is 0.04～50at%; The atomic percent of N is 0.02～82at%; Surplus is the atomic percent of Ti, can contain the small amount of impurities element, and F, O and Si etc. are arranged, and the total content of impurity element is less than 5at%.(N) compound is B, C and the sosoloid of N element in the Ti metal to Ti for B, C; Be face-centered cubic crystal structure, the Ti atom occupies the face-centered cubic lattice position, and in other element distribution clearance therebetween; Occupy position with the equivalence of Cl atom; Constitute sodium-chlor profile heart cubic crystal structure, spacer is Fm-3m, lattice parameter a _o≈ ≈ 0.4245nm.(B, C N) have definite fusing point to Ti, and when melting temperature was following, (B, C N) were the pressed powder state to Ti.(B, C are a kind of multi-element compounds N) to Ti, belong to stupalith, have good electroconductibility, and room-temperature conductivity is～10 ^-7Ω m, low-temperature superconducting transition temperature Tc=12K.It is that ceramic powder material is blank that Ti-B-C-N is filled up in the appearance of this material, for function ceramics market increases new variety.The above-mentioned Ti of the present invention (N) preparation of powdered material realizes through following operation steps for B, C:

Step 1, the compacting pressed compact

Suppress pressed compact with pressing machine: pack pure metal Ti powder in the mould into earlier, powder is exerted pressure process pressed compact then, density is 50%～90% of theoretical density;

Step 2, the preparation pack boronizing medium

The prescription of pack boronizing medium is 5～15%B-Fe (ferro-boron), 2～8% gacs, 5～10% charcoals, 2～6%KBF ₄, SiC surplus %, percentage ratio by weight;

Step 3, the preparation solid carburizer

The prescription of solid carburizer is:

85～95% charcoals and 15～5% yellow soda ash, percentage ratio by weight

Prepare solid boron carbon mixing penetration enhancer with two and three pack boronizing mediums that are mixed with and solid carburizer set by step, prescription is: the ratio of pack boronizing medium and solid carburizer is 4～9: 1

Step 5, pressed compact dress box

Be ready to magazine, with solid boron carbon mixing penetration enhancer shop fixtures, be placed on the centre to pressed compact, reach top filling solid boron carbon mixing penetration enhancer all around, the solid penetration enhancer is a particulate state; Or with the Ti powder without compacting replace the Ti pressed compact as raw material directly by the magazine of packing into upper type ";

Step 6, sintering

Be placed on sintering in the resistance furnace to the magazine that installs, resistance furnace has the cracked ammonium protective atmosphere, and gaseous constituent is: 70%N2 and 30%H2 gas, sintering temperature are 700～1200C, and the time is 2～6 hours;

Step 7, powder process

Magazine is taken out in stove, and after body to be sintered fully cooled off, the solid penetration enhancer around removing took out agglomerating titanium pressed compact, after slightly rolling, just obtained to have face-centred cubic structure high purity Ti (B, C, N) ceramic powder.

(N) synthesis mechanism of powder is pure Ti: as shown in Figure 3 for B, C; Pack boronizing medium at high temperature produces activity [B], and pack boronizing medium produces [C] atom, and active [N] atom is from from decomposed ammonia body or air; [B] and [C], [N] active atomic spread to the Ti pressed compact; Combine to produce Ti (B, C, N) compound with the Ti atom.Because the Ti pressed compact contains a large amount of holes, [B] and [C], [N] active atomic are easy to from the surface entad portion's diffusion.Diffusion reaction can make the Ti pressed compact become Ti (B, C, N) powdered material fully under the situation of and holding time long enough high in temperature.This is the innovation part that is different from other powder preparation methods.

Ti (B, C, N) formation of powder particle experience forming core and growth process, its final size depends on original Ti powder size and sintering temperature.Original size is more little, the particles of powder degree of the low more preparation of sintering temperature is more little.

In addition, (C and N atom content in N) can be very small for B, C, and the chemical formula that their content obtains seldom the time simultaneously can be expressed as TiB for Ti _x, multi-element compounds becomes blocking compound TiB _x, this moment, C and N element were little to performance impact.Wherein C and one of them content of N element is seldom the time, possibly form Ti (B, C) or Ti (B, N) binary compound powdered material.

(N) powder preparation method comprises 5 steps to Ti for B, C.

The first step is to prepare the Ti powdered material.(N) the Ti powder of powder is the Ti powder of market sale for B, C, and granularity is-200 orders or other specification to be used to prepare Ti; Purity is greater than 95% or purer.

Second step was to be pressed into pressed compact to the Ti powder, and pressed density is 50%～90% of a theoretical density.Pressed compact prepares with conventional powder metallurgy product working method.

The 3rd step was the Ti powder compact magazine of packing into, and is with solid boron carbon mixing penetration enhancer filling pressed compact, as shown in Figure 3 in magazine.

The 4th step was to be placed on the magazine that Ti pressed compact and mixing penetration enhancer are housed in the resistance sintering stove of sealing, fed the cracked ammonium protective atmosphere, carried out heat-agglomerating, and Heating temperature is 700～1200C, and soaking time is 2～6 hours.

The 5th step was to be ground into powder to agglomerate

Be fluffy lumps behind the Ti pressed compact sintering, (N) powder has pattern shown in Figure 4 for B, C to become Ti after slight the pulverizing.

Embodiment:

1, compacting pressed compact

With conventional powder metallurgy process in mould Ti powder press forming, obtain pressed compact, pressed compact is cylindrical, is of a size of Φ 12 * 15, pressing force is about 100MPa.Pressed compact weight is by the decision of film cavity volume, and its density is 50%～90% of theoretical density.

2, the titanium pressed compact magazine of packing into

Pack the titanium pressed compact in the magazine into, in magazine, surround the titanium pressed compact, to guarantee around the titanium pressed compact sufficient boronising gas being arranged with solid boron carbon penetration enhancer.

3, preparation pack boronizing medium

The composition of pack boronizing medium is 10%B-Fe (ferro-boron), 8% gac, 8% charcoal, 4%KBF ₄, 70%SiC, percentage ratio by weight, above material is particulate state, and granularity is-200～-100 orders.

4, preparation solid carburizer

The prescription of solid carburizer is:

95% charcoal and 5% yellow soda ash, percentage ratio by weight, granularity is-200～-100 orders.

5, with pack boronizing medium and solid carburizer preparation solid boron carbon mixing penetration enhancer

Pack boronizing medium and solid carburizer preparation solid boron carbon mixing penetration enhancer, prescription is: the ratio of pack boronizing medium and solid carburizer is 4～9: 1

6, sintering

In sintering oven, feed the decomposed ammonia body, gaseous constituent is N2+H ₂, flow velocity 2～4cm/s.

Be placed on the magazine that the titanium pressed compact is housed in the resistance furnace of sealing, carry out heat-agglomerating.Heating temperature is 900C, and the time is 3 hours.

7, powder process

After treating that magazine fully cools off, open cover plate, take out the agglomerating pressed compact, after slightly rolling, just obtained Ti (B, C, N) powdered material, its granularity and original Ti powder particles degree are basic identical.The composition of powdered material is: Ti70.2wt%, and B8.6wt%, C1.8wt%, N16.0wt%, O1.0wt%, F1.2wt%, Si1.2wt%, its microscopic appearance is as shown in Figure 1, and exterior appearance is as shown in Figure 4, is brown or coffee color.

Claims

1. a titanium borocarbonitride (Ti(B, C, N)) ceramic powder material, is characterized in that, described ceramic powder material is the compound that is made up of B, C and N element and Ti element, wherein B The atomic percentage is 0.02-96 at %; the atomic percentage of C is 0.04-50 at %; the atomic percentage of N is 0.02-82 at %; the balance is the atomic percentage of Ti.

2. a kind of borocarbonitride titanium (Ti(B, C, N)) ceramic powder material according to claim 1, is characterized in that, described chemical substance uses following chemical formula Ti( _Bx , _Cy , N _z ) represents, wherein x, y and z represent the chemical composition of B, C and N element respectively, and composition scope is as described in claim 1.

3. a kind of titanium borocarbonitride (Ti(B, C, N)) ceramic powder material according to claim 1 and 2, is characterized in that, described Ti (B, C, N) ceramic powder is in low At the melting temperature, it is in the state of solid powder with a crystal structure.

4. a kind of borocarbonitride titanium (Ti(B, C, N)) ceramic powder material according to claim 3, is characterized in that, described crystal structure is B, C and N element in Ti metal In a solid solution, the atoms are arranged in a sodium chloride-type face-centered cubic lattice, in which titanium atoms occupy positions equivalent to those of sodium atoms, and elements B, C and N occupy positions equivalent to chlorine atoms.

5. a kind of titanium borocarbonitride (Ti(B, C, N)) ceramic powder material according to claim 4, is characterized in that, described B, C and N are to exist in Ti( B, C, N).

6. be used for the preparation method of titanium borocarbonitride (Ti(B, C, N)) ceramic powder material described in claim 1, it is characterized in that, concrete steps are as follows:

Step 1, pressing the compact

Press the compact with a press: first put the Ti powder into the mold, and then press the powder to form a compact with a density of 50% to 90% of the theoretical density;

Step 2, preparing solid boronizing agent

The formula of the solid boronizing agent is: 5-15% B-Fe (iron boron), 2-8% activated carbon, 5-10% charcoal, 2-% 6KBF ₄ , SiC balance %;

Step 3, preparing solid carburizing agent

The formula of solid carburizing agent is: 85-95% charcoal and 15-5% sodium carbonate

Step 4, prepare solid boron carburizing agent with solid boronizing agent and solid carburizing agent

The solid boronizing agent and the solid carburizing agent prepared by steps 2 and 3 are used to prepare the solid boron carburizing agent, and the formula is: the ratio of the solid boronizing agent and the solid carburizing agent is 4 to 9: 1;

Step five, packing the compact into a box

Prepare the material box, first lay the bottom with the solid boron-carbon mixed infiltration agent prepared according to step 4, place the compact in the middle, fill the surrounding and top with solid boron-carbon mixed infiltration agent, and the solid infiltration agent is granular; The pressed Ti powder replaces the Ti compact as a raw material and directly loads into the material box according to the above method;

Step six, sintering

Put the loaded material box in the resistance furnace for sintering, the resistance furnace has a protective atmosphere, the protective atmosphere is the gas decomposed by liquid ammonia, its composition is: 70% N2 and 30% H2 gas; or directly in the resistance furnace without protective atmosphere Medium sintering, the sintering temperature is 700-1200C, and the time is 2-6 hours;

Step seven, flour making

The material box is taken out from the furnace, and after the material box is fully cooled, the sintered compact is taken out, and a high-purity Ti(B,C,N) ceramic powder with a face-centered cubic structure is obtained after slight rolling.

7. the preparation method of titanium borocarbonitride (Ti(B, C, N)) ceramic powder material according to claim 6 is characterized in that, solid boronizing agent, solid carburizing agent and protective atmosphere can be used simultaneously .

8. the preparation method of titanium borocarbonitride (Ti(B, C, N)) ceramic powder material according to claim 6, is characterized in that, above 70 ℃ solid boron carburizing agent produces active [B] simultaneously and [C] atoms; the protective atmosphere or air produces active [N] atoms, and these three active atoms react with Ti to form compounds.