CN105244245B - Silicon carbide nanometer line graphite composite cathode and preparation method thereof - Google Patents
Silicon carbide nanometer line graphite composite cathode and preparation method thereof Download PDFInfo
- Publication number
- CN105244245B CN105244245B CN201510546908.7A CN201510546908A CN105244245B CN 105244245 B CN105244245 B CN 105244245B CN 201510546908 A CN201510546908 A CN 201510546908A CN 105244245 B CN105244245 B CN 105244245B
- Authority
- CN
- China
- Prior art keywords
- graphite
- silicon carbide
- nanometer line
- base substrate
- carbide nanometer
- 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
Abstract
The invention discloses a kind of silicon carbide nanometer line graphite composite cathode and preparation method thereof.The silicon carbide nanometer line graphite composite cathode is made up of graphite cathode base substrate and silicon carbide nanometer line, silicon carbide nanometer line growth in situ and is uniformly distributed in the cutting edge position of graphite cathode base substrate.Preparation method includes（1）Mixture or Si powder with Si powder and SiC powder, is placed in reaction vessel as silicon source based on graphite cathode base substrate；（2）By reaction vessel in sintering furnace first evacuation, then pass to noble gases heat temperature raising, it is warm after, obtain silicon carbide nanometer line graphite composite cathode.The silicon carbide nanometer line graphite composite cathode of the present invention has the characteristics of long service life, uniformity are good, surface field enhancement factor is big, and preparation method is simple and convenient, with low cost.
Description
Technical field
The present invention relates to a kind of silicon carbide nanometer line-graphite composite cathode and preparation method thereof, can be applicable to strong current pulsed
The fields such as electron beam technology, High-Power Microwave.
Background technology
High-power microwave source is entered in certain electromagnetic structure by the high power electron beam of vacuum diode emission of cathode
Row beam wave energy is exchanged, and the energy of electron beam is converted into the energy of electromagnetic wave, so as to produce High-Power Microwave.Therefore negative electrode is
Vital part in High Power Microwave System.
The species of high-power microwave source cathode material is many at present, such as metallic cathode, swan shaped memory alloy and graphite cathode
Deng.Metallic cathode prepares that processing technique is simple, and the requirement to vacuum is very low, but metallic cathode is present that fusing point is low, it is relatively slow to start, etc.
The problems such as gas ions closure speed is fast, receives greatly restriction in the application of high-power microwave source；Swan shaped memory alloy is although tool
Have the advantages that transmitting threshold value is low, plasma expansion speed is little and uniformity is good, but its higher gas efficiency and shorter longevity
Life seriously governs its popularization and application in high-power microwave source；Graphite cathode has the advantages that stable and life-span length,
The important candidate material of high-power microwave source negative electrode, but graphite cathode is existed that electric current density is relatively low, emission uniformity compared with
Poor shortcoming.Paper " the Experimental studies of long-lifetime cold of A.V.Gunin et al.
cathodes for high-power microwave oscillators.IEEE Trans. Plasma Sci. 2000,
28(3): 537-541.（High-power microwave oscillator long-life cold cathode experimentation, IEEE plasma science transactions）”
Think graphite cathode and gather in threshed grain on a threshing ground cause explosive emission for typical dimpling, and ring-shaped graphite edge is substantially smoothed out after multiple-pulse number of times,
A reinforced effects is caused to weaken, emitting performance is reduced.
SiC nanowire is the new monodimension nanometer material of a class, with nanometer-scale tips and very big draw ratio, and
Electronic emission performance is excellent.Z.W. paper " Oriented Silicon Carbide Nanowires of Pan et al.:
Synthesis and Field Emission Properties. Adv. Mater., 2000, 12(6), 1186-1190
（The synthesis of orientation silicon carbide nanometer line and field emission performance, advanced material）" think that silicon carbide nanometer line has relatively low electronics
Transmitting threshold value, and electric current density is high, and emitting performance is stable." electron emission of silicon carbide nanometer line is special for the paper of Chen Zhongdao etc.
Property（Light laser and ion beam, 2010,22 (12):2945-2948）" SiC nanowire is given as high-power microwave source with flat
The example of plate cathode material, SiC nanowire negative electrode are obtained under 115kV extrinsic motivated pulse voltages and are close to 23.7kA/cm2's
Electron emission current density, more than the 14.0kA/cm of swan shaped memory alloy2, compared with swan shaped memory alloy material conventional at present,
SiC nanowire has higher electron emission current density, more preferable electron emission quality and longer service life.But
SiC nanowire can not form the negative electrode with definite shape and size, and which must be attached to just become on certain substrate has
The negative electrode of practical value.
The content of the invention
The technical problem to be solved in the present invention is to overcome the deficiencies in the prior art, there is provided a kind of long service life, uniformity
Big silicon carbide nanometer line-graphite the composite cathode of good, surface field enhancement factor, also provide it is a kind of it is simple and convenient, with low cost, can
The preparation method of the silicon carbide nanometer line of strong operability-graphite composite cathode.
To solve above-mentioned technical problem, the present invention is employed the following technical solutions：
A kind of silicon carbide nanometer line-graphite composite cathode, the silicon carbide nanometer line-graphite composite cathode are cloudy by graphite
Pole base substrate and silicon carbide nanometer line composition, the silicon carbide nanometer line growth in situ and are uniformly distributed in the graphite cathode base substrate
Cutting edge position.
Above-mentioned silicon carbide nanometer line-graphite composite cathode, it is preferred that the graphite cathode base substrate be by petroleum coke graphite,
One or more composition in crystalline flake graphite, white carbon black.
Above-mentioned silicon carbide nanometer line-graphite composite cathode, it is preferred that the graphite cathode base substrate be shaped as ring-type or
Tabular；A diameter of 100nm～600nm of the silicon carbide nanometer line, draw ratio are 100～2000.
As a total technology design, present invention also offers the system of above-mentioned silicon carbide nanometer line-graphite composite cathode
Preparation Method, specifically includes following steps：
（1）Mixture or Si powder with Si powder and SiC powder is given birth to as silicon source by silicon carbide nanometer line of graphite cathode base substrate
Long matrix, the silicon source and the graphite cathode base substrate are placed in a reaction vessel, the sword of the graphite cathode base substrate is made
Oral area position is near silicon source；
（2）The above-mentioned reaction vessel for being placed with silicon source and graphite cathode base substrate is placed in sintering furnace, stove is first evacuated to
Interior air pressure is not more than 50Pa, then passes to noble gases, and reheating is warming up to 1300 DEG C～1500 DEG C, it is warm after, be cooled to
Room temperature, obtains silicon carbide nanometer line-graphite composite cathode.
In above-mentioned preparation method, it is preferred that the step（1）In, in the mixture of the Si powder and SiC powder, Si powder contains
Measure as 10wt%～100wt%, remaining is SiC powder.
In above-mentioned preparation method, it is preferred that the step（2）In, the speed of the heat temperature raising be 2 DEG C/min～5 DEG C/
Min, the time of the insulation is 0.5h～2h.
In above-mentioned preparation method, it is preferred that the step（2）In, the temperature-fall period include first with 2 DEG C/min～5 DEG C/
The rate of temperature fall of min is cooled to 400 DEG C, then naturally cools to room temperature.
In above-mentioned preparation method, it is preferred that the step（1）In, the graphite cathode base substrate is by graphite block body Jing machines
Tool processing is prepared.
In above-mentioned preparation method, it is preferred that the step（1）In, the reaction vessel is black-fead crucible；The step
（2）In, the sintering furnace is vacuum carbon pipe sintering furnace.
In the present invention, the shape and size of graphite cathode base substrate are unrestricted, can be flat board base substrates, can be with sword
The annular base substrate of mouth, it might even be possible to be any shape and size for meeting different high-power microwave source negative electrode requirements.
In the present invention, generated in-situ SiC nanowire is formed gas-phase silicon and is occurred with negative electrode base substrate anti-by heating silicon source
The mode answered is obtained, and SiC nanowire is evenly distributed on the cutting edge position of graphite cathode base substrate, and coated graphite negative electrode base substrate completely
Cutting edge position surface.
Compared with prior art, it is an advantage of the current invention that：
1. the uniformity of the silicon carbide nanometer line of the present invention-graphite composite cathode is good.Silicon carbide nanometer line is completely covered stone
The cutting edge position of black negative electrode base substrate, and be distributed more uniform.
2. the silicon carbide nanometer line of the present invention-graphite composite cathode has larger surface field enhancement factor.Carborundum is received
Up to millimeter magnitude, draw ratio may be up to 2000 to the length of rice noodle, therefore field enhancement factor is larger.
3. the silicon carbide nanometer line of the present invention-graphite composite cathode has longer service life.Silicon carbide nanometer line from
In-situ preparation on graphite matrix, is chemical bonding, and silicon carbide nanometer line is attached to base with by silk screen printing by good bonding strength
The mode in body surface face is compared, with more preferable stability, while also having longer service life.
4. the preparation method of the silicon carbide nanometer line of the present invention-graphite composite cathode is simple, with low cost, operability
By force.Silicon carbide nanometer line-graphite composite cathode is to generate silicon carbide nanometer line in manufactured graphite cathode base substrate situ,
Secondary operations need not be carried out.
5. the preparation method of the silicon carbide nanometer line of the present invention-graphite composite cathode is on the basis of graphite cathode base substrate
SiC nanowire is formed in situ, the microcosmic field enhancement factor of graphite cathode surface not only can be significantly increased, can also be given full play to
The good electron emission capability of SiC nanowire itself.
Description of the drawings
Fig. 1 is the placement location schematic diagram of silicon source and graphite cathode base substrate in graphite crucible in the embodiment of the present invention.
Fig. 2 is the photo in kind of silicon carbide nanometer line-graphite composite cathode prepared by the embodiment of the present invention 1.
Fig. 3 is the scanning of silicon carbide nanometer line on the silicon carbide nanometer line-graphite composite cathode of the preparation of the embodiment of the present invention 1
Electron micrograph.
Marginal data：
1st, silicon source；2nd, cutting edge position；3rd, graphite crucible；4th, crucible cover；5th, silicon carbide nanometer line；6th, graphite cathode base substrate.
Specific embodiment
Below in conjunction with Figure of description and concrete preferred embodiment, the invention will be further described, but not therefore and
Limit the scope of the invention.
Material and instrument employed in following examples is commercially available.
Embodiment 1
A kind of silicon carbide nanometer line-graphite composite cathode of the present invention the, as shown in Fig. 2 silicon carbide nanometer line-graphite is multiple
Close negative electrode to be made up of graphite cathode base substrate 6 and silicon carbide nanometer line 5,5 growth in situ of silicon carbide nanometer line and be uniformly distributed in
The cutting edge position 2 of graphite cathode base substrate 6, and the surface at the cutting edge position 2 is coated on completely.
In the present embodiment, it is petroleum coke graphite that the graphite of graphite cathode base substrate 6 is constituted.
In the present embodiment, graphite cathode base substrate 6 is shaped as ring-type（Without bottom surface, or tabular）, SiC nanowire
A diameter of 100nm～600nm, draw ratio be 100～2000.
A kind of preparation method of the silicon carbide nanometer line of above-mentioned the present embodiment-graphite composite cathode, comprises the following steps：
（1）With petroleum coke graphite block body as raw material, required according to cathode size, graphite block body is processed by conventional mechanical
Method be processed into graphite cathode base substrate 6；
（2）The SiC powder of Si powder that mass percent is 10% and 90% is mixed as silicon source 1, with step（1）The stone of preparation
Based on black negative electrode base substrate 6, silicon source 1 and graphite cathode base substrate 6 are placed in graphite crucible 3, make silicon source 1 be covered in graphite crucible
3 bottom, silicon source 1 should there be the bottom of graphite crucible 3, and graphite cathode base substrate 6 is upside down in the top of graphite crucible 3, by stone
The screw thread of black 6 bottom of negative electrode base substrate is connected with the screw thread of crucible cover 4（Other machinery connection can also）, make graphite cathode base substrate 6
Cutting edge position 2 near silicon source 1, as shown in Figure 1；
（3）The above-mentioned graphite crucible 3 for being placed with silicon source 1 and graphite cathode base substrate 6 is placed in vacuum carbon pipe sintering furnace, is taken out
Vacuum is 10Pa to air pressure in burner hearth, is passed through argon, makes freeze profile into tiny structure.Then added with the heating rate of 2 DEG C/min
Heat is incubated 0.5 hour, then vacuum carbon pipe sintering furnace is reduced to 400 DEG C with the cooling rate of 2 DEG C/min to 1500 DEG C, closes
Power supply, takes out graphite crucible 3, you can obtain silicon carbide nanometer line-graphite after vacuum carbon pipe sintering furnace temperature is cooled to room temperature
Composite cathode.
The photo in kind of the silicon carbide nanometer line-graphite composite cathode as shown in Fig. 2 its electron scanning micrograph such as
Shown in Fig. 3, from the figure 3, it may be seen that a diameter of 100nm～600nm of SiC nanowire, draw ratio highest can reach 2000, and uniformly
It is covered in the surface at the cutting edge position 2 of graphite cathode base substrate 6.
In the case where the driving voltage of 608kV drives, the electric current of transmitting is 8.4kA to the silicon carbide nanometer line-graphite composite cathode,
The time delay of current emission is 0.2ns, and microwave pulsewidth is 19ns.Driving voltage of the graphite cathode of comparable size in 616kV
Under driving, the electric current of transmitting is 7.8kA, and the time delay of current emission is 0.4ns, and microwave pulsewidth is 15.8ns.Therefore, it is carbonized
The emission current of silicon nanowires-graphite the moon composite pole is larger, and the time delay of current emission is shorter, and microwave pulsewidth is larger, i.e. carbon
SiClx-graphite cathode has more preferable electron emission capability than graphite annular negative electrode.
Embodiment 2 to 7 mainly around graphite cathode base substrate 6 species and technological parameter illustrating silicon carbide nanometer line-stone
The preparation method of black composite cathode, its electron emission capability quite, are superior to graphite cathode with embodiment 1.
Embodiment 2
It is a kind of the present invention silicon carbide nanometer line-graphite composite cathode, the silicon carbide nanometer line-graphite composite cathode be by
Graphite cathode base substrate 6 and silicon carbide nanometer line 5 are constituted, and 5 growth in situ of silicon carbide nanometer line and are uniformly distributed in graphite cathode base
The cutting edge position 2 of body 6, and the surface at the cutting edge position 2 is coated on completely.
In the present embodiment, it is petroleum coke graphite that the graphite of graphite cathode base substrate 6 is constituted.
In the present embodiment, graphite cathode base substrate 6 is shaped as ring-type（It can also be tabular）.
A kind of preparation method of the silicon carbide nanometer line of above-mentioned the present embodiment-graphite composite cathode, comprises the following steps：
（1）With petroleum coke graphite block body as raw material, required according to cathode size, by side of the graphite block body by machining
Method is processed into graphite cathode base substrate 6；
（2）The SiC powder of Si powder that mass percent is 30% and 70% is mixed as silicon source 1, with step（1）The stone of preparation
Based on black negative electrode base substrate 6, silicon source 1 and graphite cathode base substrate 6 are placed in graphite crucible 3, make silicon source 1 be covered in graphite crucible
3 bottom, silicon source 1 should there be the bottom of graphite crucible 3, and graphite cathode base substrate 6 is upside down in the top of graphite crucible 3, by stone
The screw thread of black 6 bottom of negative electrode base substrate is connected with the screw thread of crucible cover 4（Other machinery connection can also）, make graphite cathode base substrate 6
Cutting edge position 2 near silicon source 1；
（3）The above-mentioned graphite crucible 3 for being placed with silicon source 1 and graphite cathode base substrate 6 is placed in vacuum carbon pipe sintering furnace, is taken out
Vacuum is 19 Pa to air pressure in burner hearth, is passed through argon, makes freeze profile into tiny structure.Then added with the heating rate of 5 DEG C/min
Heat is incubated 1 hour, then vacuum carbon pipe sintering furnace is reduced to 400 DEG C with the cooling rate of 2 DEG C/min to 1400 DEG C, closes electricity
Source, takes out graphite crucible 3, you can obtain silicon carbide nanometer line-graphite multiple after vacuum carbon pipe sintering furnace temperature is cooled to room temperature
Close negative electrode.
Embodiment 3
It is a kind of the present invention silicon carbide nanometer line-graphite composite cathode, the silicon carbide nanometer line-graphite composite cathode be by
Graphite cathode base substrate 6 and silicon carbide nanometer line 5 are constituted, and 5 growth in situ of silicon carbide nanometer line and are uniformly distributed in graphite cathode base
The cutting edge position 2 of body 6, and the surface at the cutting edge position 2 is coated on completely.
In the present embodiment, it is petroleum coke graphite that the graphite of graphite cathode base substrate 6 is constituted.
In the present embodiment, graphite cathode base substrate 6 is shaped as ring-type（It can also be tabular）.
A kind of preparation method of the silicon carbide nanometer line of above-mentioned the present embodiment-graphite composite cathode, comprises the following steps：
（1）With petroleum coke graphite block body as raw material, required according to cathode size, by side of the graphite block body by machining
Method is processed into graphite cathode base substrate 6；
（2）The SiC powder of Si powder that mass percent is 60% and 40% is mixed as silicon source 1, with step（1）The stone of preparation
Based on black negative electrode base substrate 6, silicon source 1 and graphite cathode base substrate 6 are placed in graphite crucible 3, make silicon source 1 be covered in graphite crucible
3 bottom, silicon source 1 should there be the bottom of graphite crucible 3, and graphite cathode base substrate 6 is upside down in the top of graphite crucible 3, by stone
The screw thread of black 6 bottom of negative electrode base substrate is connected with the screw thread of crucible cover 4（Other machinery connection can also）, make graphite cathode base substrate 6
Cutting edge position 2 near silicon source 1；
（3）The above-mentioned graphite crucible 3 for being placed with silicon source 1 and graphite cathode base substrate 6 is placed in vacuum carbon pipe sintering furnace, is taken out
Vacuum is 37 Pa to air pressure in burner hearth, is passed through argon, makes freeze profile into tiny structure.Then added with the heating rate of 5 DEG C/min
Heat is incubated 2 hours, then vacuum carbon pipe sintering furnace is reduced to 400 DEG C with the cooling rate of 5 DEG C/min to 1300 DEG C, closes electricity
Source, takes out graphite crucible 3, you can obtain silicon carbide nanometer line-graphite multiple after vacuum carbon pipe sintering furnace temperature is cooled to room temperature
Close negative electrode.
Embodiment 4
It is a kind of the present invention silicon carbide nanometer line-graphite composite cathode, the silicon carbide nanometer line-graphite composite cathode be by
Graphite cathode base substrate 6 and silicon carbide nanometer line 5 are constituted, and 5 growth in situ of silicon carbide nanometer line and are uniformly distributed in graphite cathode base
The cutting edge position 2 of body 6, and the surface at the cutting edge position 2 is coated on completely.
In the present embodiment, it is petroleum coke graphite that the graphite of graphite cathode base substrate 6 is constituted.
In the present embodiment, graphite cathode base substrate 6 is shaped as ring-type（It can also be tabular）.
A kind of preparation method of the silicon carbide nanometer line of above-mentioned the present embodiment-graphite composite cathode, comprises the following steps：
（1）With petroleum coke graphite block body as raw material, required according to cathode size, by side of the graphite block body by machining
Method is processed into graphite cathode base substrate 6；
（2）The SiC powder of Si powder that mass percent is 100% and 0% is mixed as silicon source 1, with step（1）The stone of preparation
Based on black negative electrode base substrate 6, silicon source 1 and graphite cathode base substrate 6 are placed in graphite crucible 3, make silicon source 1 be covered in graphite crucible
3 bottom, silicon source 1 should there be the bottom of graphite crucible 3, and graphite cathode base substrate 6 is upside down in the top of graphite crucible 3, by stone
The screw thread of black 6 bottom of negative electrode base substrate is connected with the screw thread of crucible cover 4（Other machinery connection can also）, make graphite cathode base substrate 6
Cutting edge position 2 near silicon source 1；
（3）The above-mentioned graphite crucible 3 for being placed with silicon source 1 and graphite cathode base substrate 6 is placed in vacuum carbon pipe sintering furnace, is taken out
Vacuum is 42Pa to air pressure in burner hearth, is passed through argon, makes freeze profile into tiny structure.Then added with the heating rate of 5 DEG C/min
Heat is incubated 2 hours, then vacuum carbon pipe sintering furnace is reduced to 400 DEG C with the cooling rate of 5 DEG C/min to 1300 DEG C, closes electricity
Source, takes out graphite crucible 3, you can obtain silicon carbide nanometer line-graphite multiple after vacuum carbon pipe sintering furnace temperature is cooled to room temperature
Close negative electrode.
Embodiment 5
It is a kind of the present invention silicon carbide nanometer line-graphite composite cathode, the silicon carbide nanometer line-graphite composite cathode be by
Graphite cathode base substrate 6 and silicon carbide nanometer line 5 are constituted, and 5 growth in situ of silicon carbide nanometer line and are uniformly distributed in graphite cathode base
The cutting edge position 2 of body 6, and the surface at the cutting edge position 2 is coated on completely.
In the present embodiment, it is crystalline flake graphite that the graphite of graphite cathode base substrate 6 is constituted.
In the present embodiment, graphite cathode base substrate 6 is shaped as ring-type（It can also be tabular）.
A kind of preparation method of the silicon carbide nanometer line of above-mentioned the present embodiment-graphite composite cathode, comprises the following steps：
（1）With crystalline flake graphite block as raw material, required according to cathode size, by method of the graphite block body by machining
It is processed into graphite cathode base substrate 6；
（2）The SiC powder of Si powder that mass percent is 10% and 90% is mixed as silicon source 1, with step（1）The stone of preparation
Based on black negative electrode base substrate 6, silicon source 1 and graphite cathode base substrate 6 are placed in graphite crucible 3, make silicon source 1 be covered in graphite crucible
3 bottom, silicon source 1 should there be the bottom of graphite crucible 3, and graphite cathode base substrate 6 is upside down in the top of graphite crucible 3, by stone
The screw thread of black 6 bottom of negative electrode base substrate is connected with the screw thread of crucible cover 4（Other machinery connection can also）, make graphite cathode base substrate 6
Cutting edge position 2 near silicon source 1；
（3）The above-mentioned graphite crucible 3 for being placed with silicon source 1 and graphite cathode base substrate 6 is placed in vacuum carbon pipe sintering furnace, is taken out
Vacuum is 5 Pa to air pressure in burner hearth, is passed through argon, makes freeze profile into tiny structure.Then added with the heating rate of 2 DEG C/min
Heat is incubated 0.5 hour, then vacuum carbon pipe sintering furnace is reduced to 400 DEG C with the cooling rate of 2 DEG C/min to 1500 DEG C, closes
Power supply, takes out graphite crucible 3, you can obtain silicon carbide nanometer line-graphite after vacuum carbon pipe sintering furnace temperature is cooled to room temperature
Composite cathode.
Embodiment 6
It is a kind of the present invention silicon carbide nanometer line-graphite composite cathode, the silicon carbide nanometer line-graphite composite cathode be by
Graphite cathode base substrate 6 and silicon carbide nanometer line 5 are constituted, and 5 growth in situ of silicon carbide nanometer line and are uniformly distributed in graphite cathode base
The cutting edge position 2 of body 6, and the surface at the cutting edge position 2 is coated on completely.
In the present embodiment, it is crystalline flake graphite that the graphite of graphite cathode base substrate 6 is constituted.
In the present embodiment, graphite cathode base substrate 6 is shaped as ring-type（It can also be tabular）.
A kind of preparation method of the silicon carbide nanometer line of above-mentioned the present embodiment-graphite composite cathode, comprises the following steps：
（1）With crystalline flake graphite block as raw material, required according to cathode size, by method of the graphite block body by machining
It is processed into graphite cathode base substrate 6；
（2）The SiC powder of Si powder that mass percent is 30% and 70% is mixed as silicon source 1, with step（1）The stone of preparation
Based on black negative electrode base substrate 6, silicon source 1 and graphite cathode base substrate 6 are placed in graphite crucible 3, make silicon source 1 be covered in graphite crucible
3 bottom, silicon source 1 should there be the bottom of graphite crucible 3, and graphite cathode base substrate 6 is upside down in the top of graphite crucible 3, by stone
The screw thread of black 6 bottom of negative electrode base substrate is connected with the screw thread of crucible cover 4（Other machinery connection can also）, make graphite cathode base substrate 6
Cutting edge position 2 near silicon source 1；
（3）The above-mentioned graphite crucible 3 for being placed with silicon source 1 and graphite cathode base substrate 6 is placed in vacuum carbon pipe sintering furnace, is taken out
Vacuum is 24 Pa to air pressure in burner hearth, is passed through argon, makes freeze profile into tiny structure.Then added with the heating rate of 5 DEG C/min
Heat is incubated 1 hour, then vacuum carbon pipe sintering furnace is reduced to 400 DEG C with the cooling rate of 2 DEG C/min to 1400 DEG C, closes electricity
Source, takes out graphite crucible 3, you can obtain silicon carbide nanometer line-graphite multiple after vacuum carbon pipe sintering furnace temperature is cooled to room temperature
Close negative electrode.
Embodiment 7
It is a kind of the present invention silicon carbide nanometer line-graphite composite cathode, the silicon carbide nanometer line-graphite composite cathode be by
Graphite cathode base substrate 6 and silicon carbide nanometer line 5 are constituted, and 5 growth in situ of silicon carbide nanometer line and are uniformly distributed in graphite cathode base
The cutting edge position 2 of body 6, and the surface at the cutting edge position 2 is coated on completely.
In the present embodiment, it is crystalline flake graphite that the graphite of graphite cathode base substrate 6 is constituted.
In the present embodiment, graphite cathode base substrate 6 is shaped as ring-type（It can also be tabular）.
A kind of preparation method of the silicon carbide nanometer line of above-mentioned the present embodiment-graphite composite cathode, comprises the following steps：
（1）With crystalline flake graphite block as raw material, required according to cathode size, by method of the graphite block body by machining
It is processed into graphite cathode base substrate 6；
（2）The SiC powder of Si powder that mass percent is 60% and 40% is mixed as silicon source 1, with step（1）The stone of preparation
Based on black negative electrode base substrate 6, silicon source 1 and graphite cathode base substrate 6 are placed in graphite crucible 3, make silicon source 1 be covered in graphite crucible
3 bottom, silicon source 1 should there be the bottom of graphite crucible 3, and graphite cathode base substrate 6 is upside down in the top of graphite crucible 3, by stone
The screw thread of black 6 bottom of negative electrode base substrate is connected with the screw thread of crucible cover 4（Other machinery connection can also）, make graphite cathode base substrate 6
Cutting edge position 2 near silicon source 1；
（3）The above-mentioned graphite crucible 3 for being placed with silicon source 1 and graphite cathode base substrate 6 is placed in vacuum carbon pipe sintering furnace, is taken out
Vacuum is 36 Pa to air pressure in burner hearth, is passed through argon, makes freeze profile into tiny structure.Then added with the heating rate of 5 DEG C/min
Heat is incubated 2 hours, then vacuum carbon pipe sintering furnace is reduced to 400 DEG C with the cooling rate of 2 DEG C/min to 1300 DEG C, closes electricity
Source, takes out graphite crucible 3, you can obtain silicon carbide nanometer line-graphite multiple after vacuum carbon pipe sintering furnace temperature is cooled to room temperature
Close negative electrode.
The above is only the preferred embodiment of the present invention, and protection scope of the present invention is not limited to above-mentioned enforcement
Example.All technical schemes belonged under thinking of the present invention belong to protection scope of the present invention.It is noted that for the art
Those of ordinary skill for, under the premise without departing from the principles of the invention modified and retouch, also should be regarded as the guarantor of the present invention
Shield scope.
Claims (9)
1. a kind of silicon carbide nanometer line-graphite composite cathode, it is characterised in that the silicon carbide nanometer line-graphite composite cathode
It is made up of graphite cathode base substrate and silicon carbide nanometer line, the silicon carbide nanometer line growth in situ and is uniformly distributed in the stone
The cutting edge position of black negative electrode base substrate, the graphite cathode base substrate are shaped as ring-type, the silicon carbide nanometer line-graphite compound the moon
Pole is applied to High-Power Microwave field.
2. silicon carbide nanometer line according to claim 1-graphite composite cathode, it is characterised in that the graphite cathode base
Body is made up of one or more in petroleum coke graphite, crystalline flake graphite, white carbon black.
3. silicon carbide nanometer line according to claim 1 and 2-graphite composite cathode, it is characterised in that the carborundum is received
A diameter of 100nm～600nm of rice noodle, draw ratio are 100～2000.
4. a kind of preparation method of the silicon carbide nanometer line-graphite composite cathode as any one of claims 1 to 3, wraps
Include following steps：
（1）Mixture or Si powder with Si powder and SiC powder is grown as silicon carbide nanometer line as silicon source with graphite cathode base substrate
Matrix, the silicon source and the graphite cathode base substrate are placed in a reaction vessel, the cutting edge portion of the graphite cathode base substrate is made
Position is near silicon source；
（2）The above-mentioned reaction vessel for being placed with silicon source and graphite cathode base substrate is placed in sintering furnace, gas in stove is first evacuated to
Pressure is not more than 50Pa, then passes to noble gases, and reheating is warming up to 1300 DEG C～1400 DEG C, it is warm after, be cooled to room temperature,
Obtain silicon carbide nanometer line-graphite composite cathode.
5. preparation method according to claim 4, it is characterised in that the step（1）In, the Si powder and SiC powder
In mixture, the content of Si powder is 10wt%～100wt%, and remaining is SiC powder.
6. preparation method according to claim 4, it is characterised in that the step（2）In, the speed of the heat temperature raising
For 2 DEG C/min～5 DEG C/min, the time of the insulation is 0.5h～2h.
7. the preparation method according to any one of claim 4～6, it is characterised in that the step（2）In, the drop
Warm process includes first being cooled to 400 DEG C with the rate of temperature fall of 2 DEG C/min～5 DEG C/min, then naturally cools to room temperature.
8. the preparation method according to any one of claim 4～6, it is characterised in that the step（1）In, the stone
Black negative electrode base substrate is prepared by graphite block body is machined.
9. the preparation method according to any one of claim 4～6, it is characterised in that the step（1）In, it is described anti-
Container is answered to be black-fead crucible；The step（2）In, the sintering furnace is vacuum carbon pipe sintering furnace.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510546908.7A CN105244245B (en) | 2015-08-31 | 2015-08-31 | Silicon carbide nanometer line graphite composite cathode and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510546908.7A CN105244245B (en) | 2015-08-31 | 2015-08-31 | Silicon carbide nanometer line graphite composite cathode and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN105244245A CN105244245A (en) | 2016-01-13 |
| CN105244245B true CN105244245B (en) | 2017-03-29 |
Family
ID=55041846
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510546908.7A Active CN105244245B (en) | 2015-08-31 | 2015-08-31 | Silicon carbide nanometer line graphite composite cathode and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105244245B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106278267B (en) * | 2016-08-10 | 2019-04-12 | 大连理工大学 | A kind of preparation method of growth in situ silicon carbide nanometer line enhancing porous carbon composite |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20070046598A (en) * | 2005-10-31 | 2007-05-03 | 삼성에스디아이 주식회사 | An electron emission source comprising carbon-based material and photoelectric element, a method for preparing the same, an electron emission device comprising the same and an electron emission display device comprising the same |
| CN100488873C (en) * | 2007-04-05 | 2009-05-20 | 哈尔滨工业大学 | Method for preparing one dimension SiC Nano fiber |
| CN101319368B (en) * | 2008-05-09 | 2011-01-26 | 浙江理工大学 | Method for simultaneously synthesizing SiO2 nan-wire and SiC crystal whisker |
| CN101402455B (en) * | 2008-09-22 | 2011-04-06 | 新疆天科合达蓝光半导体有限公司 | Method for producing silicon carbide nano-stick with sublimation |
| CN103928276B (en) * | 2014-04-29 | 2016-07-06 | 宁波工程学院 | A kind of method improving SiC filed emission cathode material high-temperature electronic launch stability |
-
2015
- 2015-08-31 CN CN201510546908.7A patent/CN105244245B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN105244245A (en) | 2016-01-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| TWI441937B (en) | Method for sputter targets for electrolyte films | |
| CN105836717B (en) | The preparation method of aluminium nitride electronic ceramic powder | |
| CN108048907B (en) | Preparation method of large-size and high-performance lanthanum hexaboride single crystal | |
| JP6120076B2 (en) | Cu-Ga alloy sputtering target and method for producing the same | |
| JP3433063B2 (en) | Aluminum nitride sintered body, electronic functional material and electrostatic chuck | |
| CN109437912A (en) | A kind of preparation method of the silica in situ cladding silicon carbide nuclear-shell structured nano-composite material of morphology controllable | |
| CN105244245B (en) | Silicon carbide nanometer line graphite composite cathode and preparation method thereof | |
| US10611644B2 (en) | Equipment and process for preparing silicon oxides | |
| CN105304436B (en) | Directly heated cathode and preparation method thereof | |
| CN105645982B (en) | graphite composite cathode and preparation method thereof | |
| CN107245758A (en) | A kind of multielement rare earth hexaboride（La0.6CexPr0.4‑x)B6The preparation method of monocrystal | |
| CN110896024B (en) | Silicon carbide epitaxial gallium oxide film method and silicon carbide epitaxial gallium oxide film structure | |
| CN105862131B (en) | A kind of introducing method of molybdenum when preparing molybdenum carbide crystal using MPCVD | |
| CN102226294B (en) | Modulation method for silicon-based GaN crystal structure with optimal field emission performance | |
| CN104016316B (en) | A kind of continuous preparation method of aluminum nitride powder and equipment thereof | |
| CN106653522B (en) | The preparation method of electron collector material and electron collector | |
| CN105502400A (en) | Preparation method of B4C whiskers | |
| CN203946896U (en) | A kind of equipment of continuous production aluminum nitride powder | |
| CN201927595U (en) | Miniature radiator | |
| CN205542692U (en) | Focus type tripolar structure encapsulates X ray bulb entirely based on carbon nanotube cold cathode | |
| CN108987215A (en) | A method of promoting graphene film-carbon nano-tube array composite material field emission performance | |
| CN103539087A (en) | Method of preparing aluminum nitride nanowire | |
| CN103757703B (en) | A kind of High-purity large-size silicon carbide single crystal and preparation technology thereof | |
| CN112201555A (en) | Calcium aluminate thermionic emission device and preparation method thereof | |
| CN106187203A (en) | A kind of based on aluminium carbide method preparing aluminium nitride powder and products thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |