CN109796209A

CN109796209A - One kind (Ti, Zr, Hf, Ta, Nb) B2High entropy ceramic powder and preparation method thereof

Info

Publication number: CN109796209A
Application number: CN201910180223.3A
Authority: CN
Inventors: 褚衍辉; 刘达; 叶贝琳; 周曦亚
Original assignee: South China University of Technology SCUT
Current assignee: South China University of Technology SCUT
Priority date: 2019-03-11
Filing date: 2019-03-11
Publication date: 2019-05-24
Anticipated expiration: 2039-03-11
Also published as: CN109796209B

Abstract

The invention discloses one kind (Ti, Zr, Hf, Ta, Nb) B₂High entropy ceramic powder and preparation method thereof, the preparation method are by TiO₂Powder, ZrO₂Powder, HfO₂Powder, Ta₂O₅Powder, Nb₂O₅Powder and B powder are heat-treated 1 ~ 3h under conditions of 1650 ~ 1750 DEG C after evenly mixing, pass through TiO₂、ZrO₂、HfO₂、Ta₂O₅And Nb₂O₅Boron thermal reduction reaction occurs with B and directly synthesizes (Ti, Zr, Hf, Ta, Nb) B₂High entropy ceramic powder.Not only synthesis temperature is low for the method for the present invention, simple process, high-efficient, production cost is low, but also the powder grain synthesized is tiny, ingredient is uniform.These advantages make this method have the potentiality for developing into large-scale industrial production.

Description

One kind (Ti, Zr, Hf, Ta, Nb) B2High entropy ceramic powder and preparation method thereof

Technical field

The present invention relates to belong to high entropy technical field of compound preparation, and in particular to a kind of (Ti, Zr, Hf, Ta, Nb) B₂High entropy ceramic powder and preparation method thereof.

Background technique

High entropy ceramics are a kind of new ceramic materials occurred recently, and the appearance of such ceramic material enriches existing ceramics The system of material.Late 1990s, TaiWan, China Tsinghua University professor Ye Junwei propose the concept of high entropy material, and will It is defined as element species >=5.So far, the research about high entropy material is concentrated mainly on alloy field, high-entropy alloy Specific strength is better than conventional alloys, and Resisting fractre ability, tensile strength, anticorrosive and anti-oxidation characteristics are all higher than conventional alloys. Recently, high entropy ceramics are received significant attention as a kind of new ceramic material.Compared with traditional ceramics, high entropy ceramics have higher Hardness and fusing point and better corrosion resistance, biocompatibility and chemical property etc., in superhigh temperature, biomedicine and the energy Equal fields have bigger development potentiality.The synthesis of high entropy ceramic powder is most important for the preparation and application of high entropy ceramics. However, less for the synthetic method report of high entropy ceramic powder both at home and abroad at present.

Document: " Feng L, Fahrenholtz W G, Hilmas G E, et al. Synthesis of single-phase high-entropy carbide powders. Scripta Materialia, 2019, 162: 90~ 93. " describe a kind of high entropy carbide ceramics raw powder's production technology.This method is divided into two steps: first by HfO₂、ZrO₂、 TiO₂、Nb₂O₅And Ta₂O₅Five kinds of oxide powders react to obtain carbide powder at 1600 DEG C after evenly mixing with C powder；Then again The carbide powder is heat-treated at 2000 DEG C, (Hf, Zr, Ti, Nb, Ta) C high entropy ceramic powder is made.This method is not only Preparation temperature height (2000 DEG C), complex process, and larger (average crystal grain scale reaches the high entropy ceramic powder crystallite dimension prepared 500 nm), uneven components, these disadvantages seriously limit the promotion and application of this method.

Summary of the invention

For overcome the deficiencies in the prior art, the purpose of the present invention is to provide one kind (Ti, Zr, Hf, Ta, Nb) B₂ High entropy ceramic powder and preparation method thereof, this method is with ZrO₂Powder, TiO₂Powder, HfO₂Powder, Nb₂O₅Powder, Ta₂O₅Powder and B powder are original Material, at a lower temperature by boron thermal reduction reaction directly successfully prepares that ingredient is uniform and crystal grain is tiny (Ti, Zr, Hf, Ta, Nb)B₂High entropy ceramic powder.Not only simple process, synthesis temperature are low for this method, but also prepare (Ti, Zr, Hf, Ta, Nb)B₂High entropy ceramic powder ingredient is uniform and crystal grain is tiny (average grain size is 200 ~ 300 nm).

The purpose of the present invention is achieved through the following technical solutions.

One kind (Ti, Zr, Hf, Ta, Nb) B₂The preparation method of high entropy ceramic powder, the method comprising the steps of:

(1) TiO is weighed₂Powder, ZrO₂Powder, HfO₂Powder, Nb₂O₅Powder, Ta₂O₅Powder and B(boron) powder mixing is as raw material, by grinding To mixed-powder；

(2) mixed-powder that step (1) obtains is sintered, Ar gas shielded is led in sintering process, is carried out after the completion of sintering cold But described (Ti, Zr, Hf, Ta, Nb) B is finally obtained₂High entropy ceramic powder.

Further, in step (1), the molar ratio of Ti, Zr, Hf, Nb and Ta are 1:1:1:1:1, and five kinds of oxides are total Amount and B powder molar ratio be 1:4.5 ~ 1:5.

Further, in step (1), TiO₂Powder, ZrO₂Powder, HfO₂Powder, Nb₂O₅Powder and Ta₂O₅The purity of powder >=99%, TiO₂The partial size of powder is 50 ~ 200 nm；ZrO₂Powder, HfO₂Powder, Nb₂O₅Powder and Ta₂O₅The partial size of powder is 1 ~ 3 μm；B powder it is pure Degree >=99.9%, partial size are 0.7 ~ 0.9 μm.

Further, the grinding in the step (1) be raw material is placed in ball mill polytetrafluoroethylene (PTFE) ball milling fill in, and ZrO is added₂Ball milling pearl is ground into mixed-powder.

Further, in step (1), the mass ratio of ball milling pearl and raw material used in grinding is 5:1 ~ 20:1；Ball mill Revolving speed be 300-500 r/min；Ball-milling Time is 5 ~ 20 h.

Further, in step (2), heating rate is 5 ~ 10 DEG C/min in sintering process, and sintering temperature is 1650 ~ 1750 DEG C, 1 ~ 3 h is kept the temperature after reaching sintering temperature.

The present invention is to pass through TiO₂、ZrO₂、HfO₂、Ta₂O₅And Nb₂O₅With B occur boron thermal reduction reaction directly synthesize (Ti, Zr, Hf, Ta, Nb)B₂High entropy ceramic powder.

Compared with prior art, the invention has the advantages that and the utility model has the advantages that

(1) the preparation method simple process in the present invention, preparation temperature is low, high-efficient, is conducive to large-scale industrial production；

(2) the high entropy ceramic powder crystal grain tiny (200 ~ 300 nm) and ingredient of the preparation method synthesis in the present invention are uniform, make Obtaining this method has the potentiality for developing into large-scale industrial production.

Detailed description of the invention

Fig. 1 is (Ti, Zr, Hf, Ta, the Nb) B synthesized in embodiment 1₂The XRD spectrum of high entropy ceramic powder；

Fig. 2 is (Ti, Zr, Hf, Ta, the Nb) B synthesized in embodiment 1₂The SEM of high entropy ceramic powder schemes and EDS can spectral element Plain distribution map.

Specific embodiment

Technical solution of the present invention is described in further detail below in conjunction with specific embodiments and drawings, but guarantor of the invention It protects range and embodiment is without being limited thereto.

In 1-3 of the embodiment of the present invention, the TiO of use₂Purity >=99% of powder, partial size are 50 ~ 200 nm；ZrO₂Powder Purity >=99%, partial size are 50 ~ 200 nm；HfO₂Purity >=99% of powder, partial size are 1 ~ 3 μm；Nb₂O₅The purity of powder >= 99%, partial size is 1 ~ 3 μm；Ta₂O₅Purity >=99% of powder, partial size are 1 ~ 3 μm；Purity >=99.9% of used B powder, partial size are 0.7~0.9 μm。

Embodiment 1

One kind (Ti, Zr, Hf, Ta, Nb) B₂The preparation of high entropy ceramic powder, includes the following steps:

(1) TiO of 0.48 g is weighed respectively₂The ZrO of powder, 0.74 g₂The HfO of powder, 1.26 g₂Powder, 1.32 g Ta₂O₅ Powder, 0. 80 g Nb₂O₅Powder, 1.23 g B powder are placed in the polytetrafluoroethylene (PTFE) ball grinder that capacity is 50 ml and are added 76.00 g ZrO₂Ball milling.The ball grinder is placed in ball mill, mixed powder is obtained with 13 h of revolving speed ball milling of 400 r/min Body；

(2) mixed powder obtained in step (1) is put into graphite crucible with cover and is covered tightly, which is put into very Vacuumize process is carried out in air atmosphere furnace and to atmosphere furnace, so that vacuum registration numerical value is reached 10 after vacuumizing 10 min^-2MPa, Ar gas is passed through to normal pressure, furnace temperature is risen to 1700 DEG C from room temperature with the heating rate of 8 DEG C/min later, keeps the temperature 2 h；It is then turned off Power supply cooled to room temperature leads to Ar gas shielded in whole process；

Fig. 1 is (Ti manufactured in the present embodiment_0.2Zr_0.2Hf_0.2Ta_0.2Nb_0.2)B₂The XRD spectrum of high entropy ceramic powder, the map table Bright, prepared (Ti_0.2Zr_0.2Hf_0.2Ta_0.2Nb_0.2)B₂High entropy ceramic powder is pure phase, does not contain other impurities phase.Fig. 2 is The present embodiment prepares (Ti_0.2Zr_0.2Hf_0.2Ta_0.2Nb_0.2)B₂The SEM of high entropy ceramic powder schemes and distribution diagram of element, by Fig. 2 A it is found that the (Ti synthesized under this condition_0.2Zr_0.2Hf_0.2Ta_0.2Nb_0.2)B₂High entropy ceramic powder crystallite dimension is smaller, average crystalline substance Particle size is 200 ~ 300 nm, and five kinds of components of Hf, Ta, Ti, Nb, Zr known to the b-f in Fig. 2 are uniformly distributed.

Embodiment 2

The TiO of 0.48 g is weighed respectively₂The ZrO of powder, 0.74 g₂The HfO of powder, 1.26 g₂Powder, 1.32 g Ta₂O₅Powder Body, 0.80 g Nb₂O₅Powder, 1.17 g B powder are placed in the polytetrafluoroethylene (PTFE) ball grinder that capacity is 50 ml and 28.85 g are added ZrO₂Ball milling.The ball grinder is placed in ball mill, mixed powder is obtained with 5 h of revolving speed ball milling of 300 r/min；

Mixed powder obtained in step (1) is put into graphite crucible with cover and is covered tightly, which is put into vacuum Vacuumize process is carried out in atmosphere furnace and to atmosphere furnace, so that vacuum registration numerical value is reached 10 after vacuumizing 10 min^-2MPa is passed through Furnace temperature is risen to 1650 DEG C from room temperature with the heating rate of 5 DEG C/min later, keeps the temperature 1 h by Ar gas to normal pressure；It is then turned off power supply Cooled to room temperature leads to Ar gas shielded, (Ti, Zr, Hf, Ta, the Nb) B synthesized under this condition in whole process₂High entropy Ceramic powder is pure phase, and average grain size is about 200 nm, referring to Fig. 1 and 2 of embodiment 1.

Embodiment 3

(1) TiO of 0.48 g is weighed respectively₂The ZrO of powder, 0.74 g₂The HfO of powder, 1.26 g₂Powder, 1.32 g Ta₂O₅ Powder, 0.80 g Nb₂O₅Powder, 1.30 g B powder are placed in the polytetrafluoroethylene (PTFE) ball grinder that capacity is 50 ml and are added 118.00 g ZrO₂Ball milling.The ball grinder is placed in ball mill, mixed powder is obtained with 20 h of revolving speed ball milling of 500 r/min Body；

Mixed powder obtained in step (1) is put into graphite crucible with cover and is covered tightly, which is put into vacuum Vacuumize process is carried out in atmosphere furnace and to atmosphere furnace, so that vacuum registration numerical value is reached 10 after vacuumizing 10 min^-2MPa is passed through Furnace temperature is risen to 1750 DEG C from room temperature with the heating rate of 10 DEG C/min later, keeps the temperature 3 h by Ar gas to normal pressure；It is then turned off electricity Source cooled to room temperature leads to Ar gas shielded, (Ti, Zr, Hf, Ta, the Nb) B synthesized under this condition in whole process₂It is high Entropy ceramic powder is pure phase, and average grain size is about 400 nm, referring to Fig. 1 and 2 of embodiment 1.

The above embodiment is a preferred embodiment of the present invention, but embodiments of the present invention are not by above-described embodiment Limitation, other any changes, modifications, substitutions, combinations, simplifications made without departing from the spirit and principles of the present invention, It should be equivalent substitute mode, be included within the scope of the present invention.

Claims

1. one kind (Ti, Zr, Hf, Ta, Nb) B₂The preparation method of high entropy ceramic powder, which comprises the steps of:

(1) TiO is weighed₂Powder, ZrO₂Powder, HfO₂Powder, Nb₂O₅Powder, Ta₂O₅Powder and the mixing of B powder are used as raw material, are mixed by grinding Close powder；

(2) mixed-powder that step (1) obtains is sintered, inert gas is led in sintering process, is carried out after the completion of sintering cold But, described (Ti, Zr, Hf, Ta, Nb) B is finally obtained₂High entropy ceramic powder.

2. preparation method according to claim 1, which is characterized in that in the step (1), TiO₂Powder, ZrO₂Powder, HfO₂ Powder, Nb₂O₅Powder and Ta₂O₅The purity of powder >=99%, TiO₂The partial size of powder is 50 ~ 200 nm；ZrO₂Powder, HfO₂Powder, Nb₂O₅Powder and Ta₂O₅The partial size of powder is 1 ~ 3 μm；The partial size of purity >=99.9%, B powder of B powder is 0.7 ~ 0.9 μm.

3. preparation method according to claim 1, which is characterized in that in the step (1), Ti, Zr, Hf, Nb in raw material It is 1:1:1:1:1 with the molar ratio of Ta, and TiO in raw material₂Powder, ZrO₂Powder, HfO₂Powder, Nb₂O₅Powder and Ta₂O₅Powder total amount and B powder Molar ratio be 1:4.5 ~ 1:5.

4. preparation method according to claim 1, which is characterized in that the grinding in the step (1) is to be placed in raw material During the polytetrafluoroethylene (PTFE) ball milling of ball mill fills, and ZrO is added₂Ball milling pearl is ground into mixed-powder.

5. the preparation method according to claim 4, which is characterized in that the matter of ball milling pearl and raw material used in the grinding Amount is than being 5:1 ~ 20:1.

6. the preparation method according to claim 4, which is characterized in that the revolving speed of ball mill is 300-500 r/min；Ball milling Time is 5 ~ 20 h.

7. preparation method according to claim 1, which is characterized in that in the step (2), heating rate in sintering process For 5 ~ 10 DEG C/min, sintering temperature is 1650 ~ 1750 DEG C, keeps the temperature 1 ~ 3 h after reaching sintering temperature, the inert gas is Ar Gas.

8. (Ti, Zr, Hf, Ta, Nb) B made from any one of claim 1 ~ 7 preparation method₂High entropy ceramic powder.