CN111747404B - Preparation method of temperature-equalizing graphite tube for graphite furnace - Google Patents
Preparation method of temperature-equalizing graphite tube for graphite furnace Download PDFInfo
- Publication number
- CN111747404B CN111747404B CN202010573225.1A CN202010573225A CN111747404B CN 111747404 B CN111747404 B CN 111747404B CN 202010573225 A CN202010573225 A CN 202010573225A CN 111747404 B CN111747404 B CN 111747404B
- Authority
- CN
- China
- Prior art keywords
- temperature
- graphite
- graphite tube
- heating
- coating
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B32/00—Carbon; Compounds thereof
- C01B32/20—Graphite
- C01B32/205—Preparation
Abstract
The invention discloses a temperature-equalizing graphite tube for a graphite furnace, belonging to the field of new materials. The graphite tube sprayed with the functional coating has the technical effects of preventing dissipation and ensuring the uniform temperature in the furnace, and solves the problem of pollution caused by easy volatilization of the high-temperature protective coating in the prior art.
Description
Technical Field
The invention belongs to the field of new materials, and particularly relates to a preparation method of a temperature-equalizing graphite tube for a graphite furnace.
Background
The production and scientific research of semiconductor materials, devices, integrated circuits has become an important component of the electronics industry. Parts, integrated circuits and the like made of semiconductor materials are important basic products in the electronic industry, and have great application in the fields of daily life, military and aerospace.
The growth of semiconductor materials requires a high-purity high-temperature furnace as a growth container, so that the high purity of gas molecules in the container is ensured in the high-temperature process. The currently available thermal coatings are mainly two types of silicon carbide coatings and thermally deposited graphite coatings. The uniformity of the furnace body temperature has great influence on the growth of material crystals, and the furnace body is hopeful to have excellent temperature uniformity while being clean, so that the crystal growth is more stable. However, in the prior art, the ultrahigh sintering temperature, the furnace body purity and the temperature uniformity can not be achieved at the same time. At high temperatures, silicon carbide is unstable and cannot be used as an infrared radiation layer; there is therefore a need for a high-emissivity coating that can withstand high temperatures. Meanwhile, the high-temperature coating also needs to have non-volatility so as to protect the stable existence of the graphite material at high temperature.
Disclosure of Invention
The invention aims to provide a temperature-equalizing graphite tube for a graphite furnace, which is characterized in that heat is transferred from a graphite heating body (a graphite tube body) to a temperature-equalizing coating under the frequency conversion voltage of the graphite furnace, then is rapidly transferred to graphene microspheres through pi conjugation, and finally is rapidly transferred to the whole graphite tube space through the strong heat diffusion effect of the graphene microspheres.
The invention also aims to provide a temperature-equalizing graphite tube for a graphite furnace, which comprises a temperature-equalizing coating, wherein the temperature-equalizing coating comprises graphene microspheres, and the graphene microspheres diffuse heat from a graphene protective coating to the whole graphite tube through pi conjugation. The graphene microspheres have strong specific surface area and strong infrared radiation capability, and heat is uniformly and quickly radiated to the whole graphite tube space in an infrared radiation mode.
The invention also aims to provide a uniform-temperature graphite tube for a graphite furnace, which solves the problem that a high-temperature protective coating in the prior art is easy to volatilize and cause pollution. This graphite tube inner wall has one can prevent volatile samming coating, and the preparation of this coating adopts dynamic oxidation to activate the graphite tube internal surface earlier, and the strong acid oxidizing solution of dynamic flow makes the graphite tube internal surface's graphite alkene layer take place the top and swell on the one hand to along with the liquid stream orientation of dynamic flow, improve the area of contact between the graphite tube internal surface oxidation graphite alkene and the oxidation graphite alkene of spraying, thereby make the coating stability increase. On the other hand, a large number of binding sites are generated to be combined with the sprayed graphene oxide, and the stability of the coating is improved. Furthermore, a large number of binding sites can be generated to be combined with the sprayed graphene oxide, the binding sites form defects, and the defects are combined with high-temperature carbonization and sintering, and along with defect repair, the coating and the inner surface of the graphite tube form atomic-scale combination. Furthermore, the method also adopts the graphene oxide solution with the size dispersion coefficient of more than 0.6 for spraying, and small pieces of graphene can penetrate into gaps of the interface of the graphite product to play the roles of filling and riveting, so that the stability of the interface is further enhanced. Furthermore, the graphitizable high molecular oligomer is used as a linking layer to link the graphene and the graphene microspheres, so that the interface effect is increased, and the stability and the strong binding force of the microspheres are protected.
The invention also provides a preparation method of the uniform-temperature graphite tube for the graphite furnace, which comprises the following steps:
(1) carrying out dynamic oxidation treatment on the surface of a graphite tube, specifically, immersing the graphite tube in a dynamically flowing strong acid oxidation solution; the strong acid oxidation solution is a sulfuric acid solution of A and B, wherein B is an oxide, A is a high oxide or peroxide of B, the volume mass ratio of sulfuric acid to A is between 60mL:1g and 0.1g, the mass ratio of A to B is between 1:2 and 1:5, and the oxidation time is 10min to 30 min.
(2) And cleaning with deionized water, and spraying a graphene oxide solution on the inner wall to form a film, wherein the thickness of the film is less than 100 nm. The size of the graphene oxide in the graphene oxide solution is 10-100 um, the dispersion coefficient is more than 0.6, and the concentration is 10ug/mL-1 mg/mL.
(3) After being dried, the mixture is sintered for 1 hour at 300 ℃ and then is put into a high temperature furnace for high temperature carbonization at 2000 ℃. The high-temperature carbonization procedure is as follows: heating to 1600 deg.C at 5 deg.C/min, maintaining at 1600 deg.C for 4 hr, and heating to 2000 deg.C at 20 deg.C/min; in step 4, the high-temperature carbonization procedure is as follows: heating to 500 deg.C at 5 deg.C/min, maintaining for 2 hr, heating to 1300 deg.C at 5 deg.C/min, maintaining for 4 hr at 1600 deg.C, and heating to 2800 deg.C at 20 deg.C/min.
(4) Centrifugally spraying a graphene microsphere infrared radiation coating on the inner wall, wherein the thickness of the infrared radiation coating is not more than 100 nm; the coating is a mixture of folded graphene microspheres and a graphitizable high molecular oligomer, and is dried and then sintered at 3000 ℃ for 1 hour for graphitization.
The centrifugal spraying of the inner wall can adopt the following scheme: the graphite pipe to be sprayed is rotated along the central shaft, the nozzle is arranged in the graphite pipe, and the coating is sprayed.
Further, in step 4, the size of the wrinkled graphene microspheres is 0.1-3um, the molecular weight of the graphitizable high molecular oligomer is 2000-: oligomer 10: 1.
further, A is potassium permanganate and B is manganese dioxide.
Further, A is potassium ferrate and B is iron dioxide.
Further, A is hydrogen peroxide and B is water.
The invention has the beneficial effects that: the nano coating has tight binding force, can be coated without a coarse structure, has controllable coating thickness, small thickness of the nano coating and extremely low cost. Moreover, the multi-stage heat radiation structure and the good heat convection structure design greatly improve the problem of temperature uniformity inside the furnace body, and are favorable for the growth of uniform single crystals.
Drawings
FIG. 1 is a schematic diagram of the measurement of the crystallite content per unit area.
Detailed Description
Example 1:
a preparation method of a uniform-temperature graphite tube comprises the following steps:
(1) 1g of potassium permanganate and 2g of manganese dioxide are dissolved in 60mL of concentrated sulfuric acid with the mass fraction of 98 percent to obtain a strongly acidic oxidizing solution.
Mixing large-size graphene oxide and small-size graphene oxide within the range of 10-100 um in proportion to prepare a graphene oxide solution, so that the distribution coefficient of the sizes is over 0.6.
(2) Taking a square-mouth tank with an inlet and an outlet, enabling a strong acid oxidizing solution to circularly flow from the inlet to the outlet at a flow rate of 0.1m/s, immersing the graphite tube in the flowing strong acid oxidizing solution, and soaking for 30 min.
(3) And (3) cleaning with deionized water, and spraying 10ug/mL of the graphene oxide solution prepared in the step (1) on the inner surface to form a film, wherein the thickness of the film is less than 100 nm.
(4) After being dried, the mixture is sintered for 1 hour at 300 ℃ and then is put into a high-temperature furnace for high-temperature carbonization; the high-temperature carbonization temperature process is as follows: the temperature is raised to 1600 ℃ at the rate of 5 ℃/min, the temperature is maintained at 1600 ℃ for 4 hours, and the temperature is raised to 2000 ℃ at the rate of 20 ℃/min.
(5) And centrifugally spraying graphene oxide microspheres and graphitizable high-molecular oligomers on the inner wall, drying and graphitizing at 3000 ℃. The graphitization procedure is as follows: heating to 500 ℃ at the speed of 5 ℃/min, maintaining for 2 hours, heating to 1300 ℃ at the speed of 5 ℃/min, maintaining for 4 hours at the temperature of 1300 ℃, and heating to 3000 ℃ at the speed of 20 ℃/min, maintaining for 1 hour.
Comparative examples 1 to 1
The difference from example 1 is that the inner surface of the graphite tube is oxidized in step 2 by plasma treatment.
Comparative examples 1 to 2
The difference from example 1 is that step 2 is carried out by oxidation treatment using a strongly acidic oxidizing solution in a static state.
Comparative examples 1 to 3
The difference from example 1 is that step 3 was performed by spraying a graphene oxide solution of a relatively uniform size (distribution coefficient 0.3).
The sintering-resistant frequency test method comprises the following steps: and (3) placing the graphite tube with the coating in an environment with the temperature of 2600 ℃, sintering for 2 hours, and cooling and then sintering for the next time. The sintering resistant times are as follows: until the data of the volatile microcrystals exceed the standard limit times. The standard exceeding of the volatile microcrystal data means that: the number of volatile microcrystals is more than 100 per square centimeter.
The method for testing the content of the microcrystals in the unit area comprises the following steps: laying a nano-thickness graphite film 1 prepared by a CVD method in a graphite tube, preparing a sealing cover 2 (the bottom is in a circular arc shape and is attached to the inner wall of the graphite tube) by using HOPG, and pressing the nano-thickness graphite film 1 prepared by the CVD method on the periphery, as shown in figure 1; sintering at 2600 deg.C for 2 hr. And detecting the number of microcrystals in unit area on the lower surface of the graphite film with the nanometer thickness prepared by the CVD method by a calibration method of a scanning electron microscope.
The nano-thickness graphite film 1 coated in the graphite tube prepared in example 1 has a low content of microcrystals per unit area, which is because the local orientation of the graphite tip in the vertical direction along the coating direction occurs due to dynamic oxidation and oxidative swelling, so that the coating can have excellent adhesion and adhesion effects with the graphite on the surface of the product; meanwhile, the small-size graphene is beneficial to reducing the viscosity of the solution, so that the solution can penetrate into gaps of graphite crystal grains, and the contact area and the adhesive force are increased.
The temperature difference testing method comprises the following steps: placing the graphite tube in a 50L furnace body, placing a large number of temperature measuring rings at each position of the furnace body, keeping the temperature measuring rings at 2000 ℃ for 10 minutes, taking out the temperature measuring rings, and measuring the shrinkage ratio of the temperature measuring rings. And determining the temperature difference through the shrinkage ratio difference.
Example 2:
a method for preparing a nano-graphite coating on the inner surface of a graphite tube comprises the following steps:
(1) 1g of hydrogen peroxide and 5g of water are dissolved in 600mL of concentrated sulfuric acid with the mass fraction of 98 percent to obtain a strongly acidic oxidizing solution.
Mixing large-size graphene oxide and small-size graphene oxide within the range of 10-100 um in proportion to prepare a graphene oxide solution, so that the distribution coefficient of the sizes is over 0.6.
(2) Taking a square groove with an inlet and an outlet, enabling a strong acid oxidizing solution to circularly flow from the inlet to the outlet at a flow speed of 0.1m/s, immersing the surface of the graphite tube in the flowing strong acid oxidizing solution, and soaking for 10 min.
(3) And (3) cleaning with deionized water, and spraying 1mg/mL of the graphene oxide solution prepared in the step (1) on the surface to form a film, wherein the thickness of the film is less than 100 nm.
(4) After being dried, the mixture is sintered for 1 hour at 300 ℃ and then is put into a high-temperature furnace for high-temperature carbonization; the high-temperature carbonization temperature process is as follows: heating to 1600 deg.C at 5 deg.C/min, maintaining at 1600 deg.C for 4 hr, and heating to 2000 deg.C at 20 deg.C/min;
(5) and centrifugally spraying graphene oxide microspheres and graphitizable high-molecular oligomers on the inner wall, drying and graphitizing at 3000 ℃. The graphitization procedure is as follows: heating to 500 ℃ at the speed of 5 ℃/min, maintaining for 2 hours, heating to 1300 ℃ at the speed of 5 ℃/min, maintaining for 4 hours at the temperature of 1300 ℃, and heating to 3000 ℃ at the speed of 20 ℃/min, maintaining for 1 hour.
Comparative example 2-1
The difference from the example 2 is that the plasma processing method is adopted in the step 2 to carry out oxidation treatment on the inner surface of the graphite tube.
Comparative examples 2 to 2
The difference from example 2 is that step 2 is carried out by oxidation treatment using a strongly acidic oxidizing solution in a static state.
Comparative examples 2 to 3
The difference from example 2 is that step 3 was performed using a more uniform size (distribution coefficient 0.2) graphene oxide solution.
The test method was the same as in example 1.
Example 3:
a method for preparing a nano-graphite coating on the inner surface of a graphite tube comprises the following steps:
(1) 1g of potassium ferrate and 5g of ferric oxide are dissolved in 100mL of concentrated sulfuric acid with the mass fraction of 98 percent to obtain a strongly acidic oxidizing solution.
Mixing large-size graphene oxide and small-size graphene oxide within the range of 10-100 um in proportion to prepare a graphene oxide solution, so that the distribution coefficient of the sizes is over 0.6.
(2) Taking a square groove with an inlet and an outlet, enabling the strong acid oxidizing solution to circularly flow from the inlet to the outlet at a flow rate of 0.1m/s, immersing the inner surface of the graphite tube in the flowing strong acid oxidizing solution, and soaking for 20 min.
(3) And (3) cleaning with deionized water, and spraying 0.5mg/mL of the graphene oxide solution prepared in the step (1) on the surface to form a film, wherein the thickness of the film is less than 100 nm.
(4) After being dried, the mixture is sintered for 1 hour at 300 ℃ and then is put into a high-temperature furnace for high-temperature carbonization; the high-temperature carbonization temperature process is as follows: heating to 1600 deg.C at 5 deg.C/min, maintaining at 1600 deg.C for 4 hr, and heating to 2000 deg.C at 20 deg.C/min;
(5) and centrifugally spraying the graphene oxide microspheres and the graphitizable high-molecular oligomer, and graphitizing at 3000 ℃ after drying. The graphitization procedure is as follows: heating to 500 ℃ at the speed of 5 ℃/min, maintaining for 2 hours, heating to 1300 ℃ at the speed of 5 ℃/min, maintaining for 4 hours at the temperature of 1300 ℃, and heating to 3000 ℃ at the speed of 20 ℃/min, maintaining for 1 hour.
The test method was the same as in example 1.
The obtained product has a sintering resistant frequency of 57 and a crystallite content per unit area of 21. Temperature uniformity tests were conducted at 2000 degrees on a 50L furnace body and found that the furnace temperature difference did not exceed 9 degrees Celsius and the temperature difference without the coating was around 27 degrees Celsius.
Example 4:
a method for preparing a nano-graphite coating on the inner surface of a graphite tube comprises the following steps:
(1) 1g of potassium permanganate and 2g of manganese dioxide are dissolved in 80mL of concentrated sulfuric acid with the mass fraction of 98 percent to obtain a strongly acidic oxidizing solution.
Mixing large-size graphene oxide and small-size graphene oxide within the range of 10-100 um in proportion to prepare a graphene oxide solution, so that the distribution coefficient of the sizes is over 0.6.
(2) Taking a square groove with an inlet and an outlet, enabling the strong acid oxidizing solution to circularly flow from the inlet to the outlet at a flow rate of 0.1m/s, immersing the inner surface of the graphite tube in the flowing strong acid oxidizing solution, and soaking for 10 min.
(3) And (3) cleaning with deionized water, and spraying 1mg/mL of the graphene oxide solution prepared in the step (1) on the surface to form a film, wherein the thickness of the film is less than 100 nm.
(4) After being dried, the mixture is sintered for 1 hour at 300 ℃ and then is put into a high-temperature furnace for high-temperature carbonization; the high-temperature carbonization temperature process is as follows: heating to 1600 deg.C at 5 deg.C/min, maintaining at 1600 deg.C for 4 hr, and heating to 2000 deg.C at 20 deg.C/min;
(5) and centrifugally spraying the graphene oxide microspheres and the graphitizable high-molecular oligomer, and graphitizing at 3000 ℃ after drying. The graphitization procedure is as follows: heating to 500 ℃ at the speed of 5 ℃/min, maintaining for 2 hours, heating to 1300 ℃ at the speed of 5 ℃/min, maintaining for 4 hours at the temperature of 1300 ℃, and heating to 3000 ℃ at the speed of 20 ℃/min, maintaining for 1 hour.
The test method was the same as in example 1.
The obtained product has the sintering resistant times of 61 and the content of microcrystals in unit area of 9. Meanwhile, a temperature uniformity test of a 50L furnace body at 2000 ℃ shows that the temperature difference of the furnace is not more than 12 ℃, and the temperature difference without a coating is about 31 ℃.
Claims (4)
1. The preparation method of the temperature-equalizing graphite tube for the graphite furnace is characterized in that the graphite tube comprises a graphite tube body and a temperature-equalizing coating on the inner wall of the graphite tube, and is prepared by the following steps:
(1) carrying out dynamic oxidation treatment on the surface of a graphite tube, specifically, immersing the graphite tube in a dynamically flowing strong acid oxidation solution; the strong acid oxidation solution is a sulfuric acid solution of A and B, wherein B is an oxide, A is a high oxide or peroxide of B, the volume mass ratio of sulfuric acid to A is between 60mL:1g and 0.1g, the mass ratio of A to B is between 1:2 and 1:5, and the oxidation time is 10min to 30 min;
(2) cleaning with deionized water, spraying a graphene oxide solution on the inner wall to form a film, wherein the thickness of the film is less than 100 nm; the size of the graphene oxide in the graphene oxide solution is 10-100 um, the dispersion coefficient is more than 0.6, and the concentration is 10ug/mL-1 mg/mL;
(3) after air drying, sintering for 1 hour at 300 ℃, and then placing in a high-temperature furnace for high-temperature carbonization at 2000 ℃; the high-temperature carbonization procedure is as follows: heating to 1600 deg.C at 5 deg.C/min, maintaining at 1600 deg.C for 4 hr, and heating to 2000 deg.C at 20 deg.C/min;
(4) centrifugally spraying a graphene microsphere infrared radiation coating on the inner wall, wherein the thickness of the infrared radiation coating is not more than 100 nm; the coating is a mixture of folded graphene microspheres and a graphitizable high-molecular oligomer, the size of the folded graphene microspheres is 0.1-3um, the molecular weight of the graphitizable high-molecular oligomer is 2000-20000, and the mass ratio is microsphere: oligomer = 10: 1; after drying, graphitizing at 3000 ℃; the graphitization procedure is as follows: heating to 500 ℃ at the speed of 5 ℃/min, maintaining for 2 hours, heating to 1300 ℃ at the speed of 5 ℃/min, maintaining for 4 hours at the temperature of 1300 ℃, and heating to 3000 ℃ at the speed of 20 ℃/min, maintaining for 1 hour.
2. The method of claim 1, wherein a is potassium permanganate and B is manganese dioxide.
3. The method of claim 1, wherein a is potassium ferrate and B is iron dioxide.
4. The method of claim 2, wherein A is hydrogen peroxide and B is water.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010573225.1A CN111747404B (en) | 2020-06-22 | 2020-06-22 | Preparation method of temperature-equalizing graphite tube for graphite furnace |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010573225.1A CN111747404B (en) | 2020-06-22 | 2020-06-22 | Preparation method of temperature-equalizing graphite tube for graphite furnace |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111747404A CN111747404A (en) | 2020-10-09 |
| CN111747404B true CN111747404B (en) | 2021-11-30 |
Family
ID=72674886
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010573225.1A Active CN111747404B (en) | 2020-06-22 | 2020-06-22 | Preparation method of temperature-equalizing graphite tube for graphite furnace |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111747404B (en) |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103663444B (en) * | 2013-12-17 | 2015-12-02 | 张家港康得新光电材料有限公司 | A kind of Graphene composite film for heat dissipation and preparation method thereof |
| CN106085104A (en) * | 2016-06-14 | 2016-11-09 | 深圳市鑫成炭素科技有限公司 | Infrared heat radiation coating of Graphene and preparation method thereof |
| CN108997983A (en) * | 2018-07-19 | 2018-12-14 | 皖西学院 | The preparation method and application of three-dimensional drape shape graphene heat dissipation slurry |
| CN209710562U (en) * | 2018-12-04 | 2019-11-29 | 广东智科精创科技股份有限公司 | A kind of temperature uniforming heat radiation piece |
| CN109673067B (en) * | 2018-12-21 | 2021-08-06 | 河南烯碳合成材料有限公司 | Metal-based graphene high-temperature-resistant far-infrared heating tube and preparation method thereof |
| CN110182793B (en) * | 2019-06-26 | 2022-02-08 | 东旭光电科技股份有限公司 | Preparation method of high-thermal-conductivity graphene radiating fin |
| CN111233515B (en) * | 2020-03-19 | 2022-04-22 | 北京晶龙特碳科技有限公司 | Method for preparing nano-graphite coating on surface of graphite product |
-
2020
- 2020-06-22 CN CN202010573225.1A patent/CN111747404B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN111747404A (en) | 2020-10-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Chen et al. | Thermochemistry and growth mechanism of SiC nanowires | |
| Chen et al. | A simple catalyst-free route for large-scale synthesis of SiC nanowires | |
| CN102600775B (en) | SiC-graphene nano-composite and preparation method thereof | |
| CN104925794B (en) | A kind of taking nano-pore Graphene as substrate grown the method for three-dimensional nitrogen-doped graphene | |
| CN110066175B (en) | Preparation method of ultralight carbide ceramic foam | |
| CN104451957B (en) | Low density SiC nanofiber and its preparation method | |
| Chen et al. | Static and dynamic oxidation behaviour of silicon carbide at high temperature | |
| CN111233515B (en) | Method for preparing nano-graphite coating on surface of graphite product | |
| CN104532549A (en) | Method for rapidly obtaining carbon/silicon carbide coaxial fiber by reducing plasma based on microwave and application | |
| CN100488873C (en) | Method for preparing one dimension SiC Nano fiber | |
| Wang et al. | Scalable in situ growth of SnO2 nanoparticle chains on SiC ultrathin fibers via a facile sol–gel-flame method | |
| CN112048197A (en) | Furnace body temperature-equalizing radiation coating and preparation method thereof | |
| CN111747404B (en) | Preparation method of temperature-equalizing graphite tube for graphite furnace | |
| Zhang et al. | In-situ preparation of carbon nanotubes on CuO nanowire via chemical vapor deposition and their growth mechanism investigation | |
| CN109279605A (en) | A kind of hafnium carbide preparation method | |
| Duan et al. | Oxidation and ablation behavior of a ceramizable resin matrix composite based on carbon fiber/phenolic resin | |
| CN1330796C (en) | Method of synthetizing two kinds of different shaped silicon carbid nano wire | |
| CN112707433B (en) | Preparation method of rare earth cerium doped gallium oxide nano material | |
| Shim et al. | The effect of temperature and atmospheric-pressure on mechanical and electrical properties of polymer-derived SiC fibers | |
| IES87256Y1 (en) | Method for preparing temperature-uniformizing graphite pipe for graphite furnace | |
| CN114380612A (en) | Preparation method of low-loss high-oxidation-resistance silicon carbide fiber reinforced zirconia-zirconium tungstate ceramic composite material | |
| Cheng et al. | Graphene-coated pearl-chain-shaped SiC nanowires | |
| CN110420650B (en) | Preparation method of Bi/BiOBr composite material with core-shell structure | |
| CN104773735A (en) | Preparation method of ultra-long SiC nanowires | |
| CN111410560A (en) | Preparation method of silicified graphite with high-density SiC coating |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |