CN114501763A - Cathode head of plasma torch and preparation method thereof - Google Patents
Cathode head of plasma torch and preparation method thereof Download PDFInfo
- Publication number
- CN114501763A CN114501763A CN202011155686.3A CN202011155686A CN114501763A CN 114501763 A CN114501763 A CN 114501763A CN 202011155686 A CN202011155686 A CN 202011155686A CN 114501763 A CN114501763 A CN 114501763A
- Authority
- CN
- China
- Prior art keywords
- hafnium
- cathode
- tantalum
- transition layer
- carbide
- 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.)
- Pending
Links
- 238000002360 preparation method Methods 0.000 title claims abstract description 12
- 239000011248 coating agent Substances 0.000 claims abstract description 45
- 238000000576 coating method Methods 0.000 claims abstract description 45
- VBJZVLUMGGDVMO-UHFFFAOYSA-N hafnium atom Chemical compound [Hf] VBJZVLUMGGDVMO-UHFFFAOYSA-N 0.000 claims abstract description 37
- 238000005507 spraying Methods 0.000 claims abstract description 36
- 230000007704 transition Effects 0.000 claims abstract description 35
- 229910052735 hafnium Inorganic materials 0.000 claims abstract description 31
- 238000005245 sintering Methods 0.000 claims abstract description 31
- 229910001339 C alloy Inorganic materials 0.000 claims abstract description 28
- DOTRQBVTSROBAH-UHFFFAOYSA-N [C].[Ta].[Hf] Chemical compound [C].[Ta].[Hf] DOTRQBVTSROBAH-UHFFFAOYSA-N 0.000 claims abstract description 28
- 238000000034 method Methods 0.000 claims abstract description 26
- WHJFNYXPKGDKBB-UHFFFAOYSA-N hafnium;methane Chemical compound C.[Hf] WHJFNYXPKGDKBB-UHFFFAOYSA-N 0.000 claims abstract description 23
- 229910026551 ZrC Inorganic materials 0.000 claims abstract description 21
- OTCHGXYCWNXDOA-UHFFFAOYSA-N [C].[Zr] Chemical compound [C].[Zr] OTCHGXYCWNXDOA-UHFFFAOYSA-N 0.000 claims abstract description 21
- 229910052751 metal Inorganic materials 0.000 claims abstract description 12
- 239000002184 metal Substances 0.000 claims abstract description 12
- 229910001029 Hf alloy Inorganic materials 0.000 claims abstract description 7
- 239000000126 substance Substances 0.000 claims abstract description 4
- 239000000463 material Substances 0.000 claims description 31
- 239000000843 powder Substances 0.000 claims description 19
- 238000007751 thermal spraying Methods 0.000 claims description 18
- QKQUUVZIDLJZIJ-UHFFFAOYSA-N hafnium tantalum Chemical compound [Hf].[Ta] QKQUUVZIDLJZIJ-UHFFFAOYSA-N 0.000 claims description 6
- 125000004432 carbon atom Chemical group C* 0.000 claims description 5
- 238000004519 manufacturing process Methods 0.000 claims 2
- 230000008569 process Effects 0.000 abstract description 19
- 238000002679 ablation Methods 0.000 abstract description 5
- 239000013078 crystal Substances 0.000 abstract description 3
- 239000010410 layer Substances 0.000 description 27
- 239000007789 gas Substances 0.000 description 21
- 230000000052 comparative effect Effects 0.000 description 11
- 239000010406 cathode material Substances 0.000 description 9
- -1 hafnium tantalum pentacarbonate Chemical compound 0.000 description 8
- 239000000203 mixture Substances 0.000 description 8
- 238000007750 plasma spraying Methods 0.000 description 7
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 6
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 6
- 239000002994 raw material Substances 0.000 description 5
- 229910045601 alloy Inorganic materials 0.000 description 4
- 239000000956 alloy Substances 0.000 description 4
- 238000001816 cooling Methods 0.000 description 4
- 238000010438 heat treatment Methods 0.000 description 4
- 229910052786 argon Inorganic materials 0.000 description 3
- 238000002425 crystallisation Methods 0.000 description 3
- 230000008025 crystallization Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 229910052757 nitrogen Inorganic materials 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 239000003153 chemical reaction reagent Substances 0.000 description 2
- 239000011247 coating layer Substances 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 238000010494 dissociation reaction Methods 0.000 description 2
- 230000005593 dissociations Effects 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 230000017525 heat dissipation Effects 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- 125000004435 hydrogen atom Chemical class [H]* 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000002035 prolonged effect Effects 0.000 description 2
- 238000001878 scanning electron micrograph Methods 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 230000004075 alteration Effects 0.000 description 1
- 238000009770 conventional sintering Methods 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000002490 spark plasma sintering Methods 0.000 description 1
- 238000004627 transmission electron microscopy Methods 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05H—PLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
- H05H1/00—Generating plasma; Handling plasma
- H05H1/24—Generating plasma
- H05H1/26—Plasma torches
- H05H1/32—Plasma torches using an arc
- H05H1/34—Details, e.g. electrodes, nozzles
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
- C23C4/04—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge characterised by the coating material
- C23C4/10—Oxides, borides, carbides, nitrides or silicides; Mixtures thereof
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
- C23C4/12—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge characterised by the method of spraying
- C23C4/134—Plasma spraying
Abstract
The invention discloses a cathode head of a plasma torch and a preparation method thereof, wherein the cathode head comprises a hafnium cathode core, a hafnium carbide or zirconium carbide transition layer and a tantalum-hafnium-carbon alloy coating from inside to outside; the cathode core is made of metal simple substance hafnium or hafnium alloy. According to the invention, the tantalum-hafnium-carbon alloy coating is adopted to protect the hafnium cathode core, and further hafnium carbide or zirconium carbide is used as a transition layer for pre-spraying, so that the interface stress between the tantalum-hafnium-carbon alloy coating and the hafnium cathode core is overcome, and the problem that the coating is easy to crack due to the fact that the thermal expansion coefficients of the cathode core and the tantalum-hafnium-carbon alloy coating are inconsistent is solved. The invention further enables the tantalum-hafnium-carbon alloy coating to have a complete crystal structure through a rapid sintering process, and improves the ablation resistance and the high temperature resistance of the plasma torch cathode head, thereby prolonging the service life of the plasma torch cathode head.
Description
Technical Field
The invention relates to the technical field of plasma torches, in particular to a cathode head of a plasma torch.
Background
The plasma torch, also called a plasma torch, is a discharge device capable of generating directional low-temperature (about 2000-20000K) plasma jet. Plasma torches can be classified into four types, i.e., an argon torch, a nitrogen torch, an air torch, and a steam torch according to different types of media, wherein the research on the steam torch is relatively small.
At present, the cathode head of the steam torch mainly uses metal hafnium as an application material, but the service life of the metal hafnium as the cathode of the steam torch under the power condition of 50kW is difficult to reach the application requirement.
Therefore, there is a need to develop a new cathode head of a plasma torch to extend the life of the cathode material in the plasma torch.
Disclosure of Invention
In order to solve the problems in the prior art, an object of the present invention is to provide a cathode head of a plasma torch, which can prolong the life of a cathode material in the plasma torch.
In order to realize the purpose of the invention, the technical scheme of the invention is as follows:
in a first aspect, the invention provides a cathode head of a plasma torch, comprising, from inside to outside, a cathode core, a hafnium carbide or zirconium carbide transition layer, a tantalum-hafnium-carbon alloy coating; the cathode core is made of metal simple substance hafnium or hafnium alloy.
Preferably, the thickness of the hafnium carbide or zirconium carbide transition layer is 1 to 15 μm.
Preferably, the thickness of the tantalum-hafnium-carbon alloy coating is 10-100 μm.
In a second aspect, the present invention provides a method for preparing a cathode head of a plasma torch, comprising the steps of:
(1) spraying a transition layer material hafnium carbide or zirconium carbide on the surface of the cathode core;
(2) spraying a coating material of tantalum hafnium (Ta) with five carbon atoms on the surface obtained in the step (1)4HfC5)；
(3) And (3) sintering the obtained material in the step (2) to completely crystallize the transition layer material and the coating material.
Preferably, the plasma thermal spraying is adopted in the step (1), the powder feeding gas pressure is 0.65MPa to 0.95MPa, and the powder feeding speed is 45g/min to 55 g/min.
Preferably, the step (2) adopts plasma thermal spraying, the pressure of powder feeding gas is 0.55MPa to 0.75MPa, and the powder feeding speed is 35g/min to 45 g/min.
Further, the sintering temperature in the step (3) is 800-1760 ℃, and the sintering is stopped until the transition layer and the tantalum-hafnium-carbon alloy coating are completely crystallized.
Preferably, the sintering temperature is controlled to be 1300-1450 ℃, and the sintering time is controlled to be within 30 minutes.
It should be noted that the surface of the cathode core described in the foregoing preparation method of the present invention does not include the contact surface of the cathode core and the base, i.e., the contact surface of the cathode core and the base does not need to be sprayed with the transition layer material and the coating material.
In a third aspect, the present invention provides a plasma torch comprising the aforementioned cathode head of the present invention.
The raw materials or reagents involved in the invention are all common commercial products, and the operations involved are all routine operations in the field unless otherwise specified.
The above-described preferred conditions may be combined with each other to obtain a specific embodiment, in accordance with common knowledge in the art.
The invention has the beneficial effects that:
the invention adopts the tantalum-hafnium-carbon alloy coating to protect the hafnium cathode core, and the tantalum-hafnium-carbon alloy coating has a complete crystal structure through a rapid sintering process, so that the ablation resistance and the high temperature resistance of the plasma torch cathode head are improved, and the service life of the plasma torch cathode head is prolonged.
In the spraying process of the tantalum-hafnium-carbon alloy coating, hafnium carbide or zirconium carbide is further used as a transition layer for spraying in advance, so that the interface stress between the tantalum-hafnium-carbon alloy coating and a hafnium cathode core is overcome, the problem that the coating is easy to crack due to the fact that the thermal expansion coefficients of the cathode core and the tantalum-hafnium-carbon alloy coating are inconsistent is solved, and the tantalum-hafnium-carbon alloy coating is prevented from falling off due to overlarge interface stress in the sintering process of an ion torch.
The invention further controls the crystallization degree of the transition layer by controlling the speed and the temperature of the thermal spraying, improves the binding force of the tantalum hafnium carbon alloy coating and the hafnium cathode core, and prevents the external tantalum hafnium carbon alloy coating from falling off due to high-temperature ablation in the use process of the plasma torch cathode.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description, serve to explain the principles of the invention.
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without inventive exercise.
FIG. 1 is a cathode interface morphology image detected by SEM of a cathode head prepared by the preparation method of the invention in an experimental example of the invention.
FIG. 2 is SEM images of cathode heads prepared in comparative example 1 and comparative example 2 in the experimental example of the present invention; wherein (a) is comparative example 1 and (b) is comparative example 2.
FIG. 3 shows the comparison of the life of the cathode material in the experimental examples of the present invention.
FIG. 4 shows TEM results of hafnium cathode alloy cores and pure hafnium cores in the experimental examples of the present invention; wherein, (a) is alloy hafnium, and (b) is pure metal hafnium.
Detailed Description
The object of the present invention is to provide a cathode head for a plasma torch, which prolongs the life of the cathode material in the plasma torch.
The cathode head of the plasma torch comprises a cathode core, a hafnium carbide or zirconium carbide transition layer and a tantalum-hafnium-carbon alloy coating from inside to outside; the cathode core is made of metal simple substance hafnium or hafnium alloy.
Wherein, the purity of the tantalum-hafnium-carbon alloy coating is more than 99%, and the purity of the hafnium carbide or the zirconium carbide transition layer is more than 99%.
In a specific embodiment of the present invention, the thickness of the hafnium carbide or zirconium carbide transition layer is preferably 1 to 15 μm.
If the thickness of the transition layer is too low, the bonding force between the tantalum-hafnium-carbon alloy coating and the cathode core cannot be effectively improved, and the effect on prolonging the service life of the cathode head is limited; if the transition layer is too thick, the transition layer is likely to fall off due to the tensile force.
In an embodiment of the invention, the thickness of the tantalum hafnium carbon alloy coating is preferably 10 to 100 μm.
The invention further provides a preparation method of the plasma torch cathode head, which comprises the following steps:
(1) spraying a transition layer material hafnium carbide or zirconium carbide on the surface of the cathode core;
(2) spraying a coating material of tantalum hafnium (Ta) with five carbon atoms on the surface obtained in the step (1)4HfC5)；
(3) And (3) sintering the obtained material in the step (2) to completely crystallize the transition layer material and the coating material.
In a specific embodiment of the present invention, the hafnium carbide powder has a particle size of 2 to 5 μm, and the zirconium carbide powder has a particle size of 5 to 8 μm.
Further, the spraying process of the transition layer material specifically comprises the following steps: carrying out plasma thermal spraying on the hafnium carbide or zirconium carbide powder by a thermal spraying machine to obtain a hafnium carbide/zirconium carbide coating, wherein the current is 600-650A and the voltage is 65-70V during thermal spraying;
the main gas in the plasma spraying process is argon, the main gas is monoatomic gas, high-frequency arcing is easy, and the arc maintenance stability is good. Further, controlling the main gas pressure in the plasma spraying process to be 0.6-0.8 MPa, and controlling the gas flow in the spraying process to be 40-45 lpm;
the auxiliary gas in the plasma spraying process is hydrogen, the dissociation energy and the heat conductivity coefficient are high, the density is small, and the auxiliary gas has positive contribution to the arc voltage and the arc temperature;
the powder feeding gas in the plasma spraying process is nitrogen, the pressure of the powder feeding gas is 0.55MPa to 0.75MPa, and the powder feeding rate is 35g/min to 45g/min, preferably 40 g/min.
Preferably, the thickness of the hafnium carbide transition layer is less than 10 μm and the thickness of the zirconium carbide transition layer is less than 15 μm.
In a specific embodiment of the invention, the powder particle size of the hafnium tantalum pentacarbonate is 10 to 15 μm.
Further, the spraying process of the coating material of the tantalum hafnium tetra-carbon concretely comprises the following steps: performing plasma thermal spraying on the five-carbon hafnium-tantalum-hydride powder by adopting a thermal spraying machine to obtain a coating, wherein the current is 630-700A and the voltage is 65-70V during the thermal spraying;
argon is used as main gas in the plasma spraying process, the pressure of the main gas is 0.7-0.9 MPa, and the gas flow in the spraying process is 55-65 lpm;
the auxiliary gas in the plasma spraying process is hydrogen, the dissociation energy and the heat conductivity coefficient are high, the density is small, and the auxiliary gas has positive contribution to the arc voltage and the arc temperature;
the powder feeding gas in the plasma spraying process is nitrogen, the pressure of the powder feeding gas is 0.65MPa to 0.95MPa, and the powder feeding speed is 45g/min to 55g/min, preferably 50 g/min.
In the spraying process, the phase transition temperature of the tantalum hafnium penta-carbon tetra-alloy is higher, and the thermal spraying temperature can not enable the material to be completely crystallized, so that secondary sintering is needed to increase the integrity of the crystallization of the material, the improvement of the crystallization degree can improve the bonding force of the tantalum hafnium carbon alloy coating, and the service life of the cathode head is further prolonged.
Specifically, the sprayed cathode material is placed in a rapid sintering furnace for sintering, and the interface between the metal hafnium and the zirconium carbide/hafnium carbide is seriously diffused due to the conventional sintering, so that the integrity of the interface is ensured by using the rapid sintering furnace. The sintering temperature is controlled to be 800-1760 ℃, and the sintering is stopped until the transition layer and the tantalum-hafnium-carbon alloy coating are completely crystallized. Further, XRD phase test results show that the sintering effect is best in the temperature range of 1300-1450 ℃, and the sintering time is usually controlled within 30 minutes.
Because the cathode head needs to be contacted with the copper base for heat dissipation, the contact surface of the cathode core and the copper base is not required to be sprayed with the coating, the treatment mode of the contact surface is the same as the conventional treatment mode in the field, and the sintering is carried out by utilizing Spark Plasma Sintering (SPS).
In order that the above objects, features and advantages of the present invention may be more clearly understood, a solution of the present invention will be further described below. It should be noted that the embodiments and features of the embodiments of the present invention may be combined with each other without conflict.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other ways than those described herein; it is to be understood that the embodiments described in this specification are only some embodiments of the invention, and not all embodiments.
The preferred embodiments of the present invention will be described in detail with reference to the following examples. It is to be understood that the following examples are given for illustrative purposes only and are not intended to limit the scope of the present invention. Various modifications and alterations of this invention will become apparent to those skilled in the art without departing from the spirit and scope of this invention.
The experimental procedures used in the following examples are all conventional procedures unless otherwise specified.
Materials, reagents and the like used in the following examples are commercially available unless otherwise specified.
Example 1
This example is for explaining a cathode head of a plasma torch and a method for preparing the same according to the present invention.
1. Raw materials
Metallic hafnium cathode core, hafnium carbide, tantalum hafnium penta-carbon (Ta)4HfC5)；
2. Preparation method
(1) Spraying hafnium carbide on the surface of the cathode core by a thermal spraying machine under the spraying condition of 1050 ℃ and the spraying thickness of 2.5 mu m;
(2) spraying tantalum hafnium (Ta) with five carbon atoms on the surface obtained in the step (1) by adopting a thermal spraying machine4HfC5) The spraying condition is 1430 ℃, and the spraying thickness is 80 mu m;
(3) after the spraying is finished, the mixture is placed in a high-temperature gas sintering furnace for sintering, the temperature is raised to 1430 ℃ at the average heating rate of 50 ℃/min, the mixture is sintered for 60min, inert gas is introduced in the whole process to completely crystallize the transition layer material and the coating material, and then the mixture is cooled to the room temperature at the cooling rate of 30 ℃/min.
Example 2
This example is for explaining the cathode head of a plasma torch and the method for preparing the same according to the present invention.
1. Raw materials
Hafnium alloy cathode core, zirconium carbide, tantalum hafnium (Ta) penta-carbon tetra-oxide4HfC5)；
2. Preparation method
(1) Spraying zirconium carbide on the surface of the cathode core by a thermal spraying machine under the spraying condition of 1200 ℃ and the spraying thickness of 2 mu m;
(2) spraying tantalum hafnium (Ta) with five carbon atoms on the surface obtained in the step (1) by adopting a thermal spraying machine4HfC5) The spraying condition is 1430 ℃, and the spraying thickness is 80 mu m;
(3) after the spraying is finished, the mixture is placed in a high-temperature gas sintering furnace for sintering, the temperature is increased to 1350 ℃ at the average heating rate of 50 ℃/min, the mixture is sintered for 75min, the transition layer material and the coating material are completely crystallized, and then the temperature is reduced to the room temperature at the cooling rate of 30 ℃/min.
Example 3
This example differs from example 1 in that a hafnium alloy cathode core is used in place of a metallic hafnium cathode core.
Example 4
This example differs from example 2 in that a hafnium metal cathode core is used in place of a hafnium alloy cathode core.
Comparative example 1
1. Raw materials: a metallic hafnium cathode core, hafnium carbide;
2. preparation method
(1) Spraying hafnium carbide on the surface of the cathode core by a thermal spraying machine under the spraying condition of 1050 ℃ and the spraying thickness of 2.5 mu m;
(2) after the spraying is finished, the mixture is placed in a high-temperature gas sintering furnace for sintering, the temperature is raised to 1050 ℃ at the heating rate of 50 ℃/min, the sintering time is 30min, the coating material is completely crystallized, and then the temperature is lowered to the room temperature at the cooling rate of 30 ℃/min.
Comparative example 2
1. Raw materials
Hafnium metal cathode core, tantalum hafnium penta-carbon (Ta) tetraoxide4HfC5)；
2. Preparation method
(1) Spraying tantalum hafnium tetracarbonate on the surface of the cathode core by using a thermal spraying machine under the spraying condition of 1430 ℃ and the spraying thickness of 80 mu m;
(2) after the spraying is finished, the mixture is placed in a high-temperature sintering furnace for sintering, the temperature is increased to 1430 ℃ at the heating rate of 50 ℃/min, the mixture is sintered for 80min, the coating material is completely crystallized, and then the temperature is reduced to the room temperature at the cooling rate of 30 ℃/min.
Examples of the experiments
1. Detecting an object
Cathode heads, pure metal hafnium cathode cores (without coating) prepared in example 1, example 4, comparative examples 1-2.
2. Detection method
2.1 bonding between cathode core, transition layer and tantalum hafnium carbon alloy coating
The cathode head was observed in cross section by SEM scanning to examine whether the bond between the cathode core, the transition layer, and the tantalum-hafnium-carbon alloy coating layer was defective.
2.2 cathode Material Life
The cathode head prepared in examples 1 and 4 and a pure hafnium cathode core prepared in examples 5.5mm in diameter were tested on a plasma steam torch with a power of 50KW, and the time for cathode core ablation (10mm length completely burned) was used to characterize the life of the cathode material.
2.3 Transmission Electron microscopy testing
And verifying the microstructures of the alloy cathode hafnium core and the pure hafnium core by using a transmission electron microscope.
3. The result of the detection
3.1 scanning Electron microscope
The SEM images of the cathode heads prepared in example 1 and example 4 are similar without significant difference, and it can be seen from fig. 1 that the cathode core and the transition layer of the cathode head prepared by the preparation method of the present invention have complete bonding, and the transition layer and the tantalum hafnium carbon alloy coating have complete bonding without defects.
The cathode head prepared in comparative example 1 has a cathode interface morphology image detected by SEM as shown in fig. 2(a), and the hafnium metal is relatively completely bonded with the transition layer, and has few defects.
The cathode head prepared in comparative example 2 has a cathode interface morphology image detected by SEM as shown in FIG. 2(b), and the cross section of the direct bonding of metal hafnium and tantalum hafnium pentacarbon tetraoxide has a convex part, which can accelerate the melting of the material during the ablation process.
3.2 cathode Material Life
As shown in FIG. 3, the lifetime of the water vapor ion torch of the cathode head prepared using the pure hafnium material was 168 hours, the lifetime of comparative example 1 was 172 hours, and the lifetime of comparative example 2 was 162 hours, whereas the lifetimes of both the metal hafnium/hafnium carbide/tetratantalate pentacarbide (example 1) and the metal hafnium/zirconium carbide/tetratantalate pentacarbide (example 4) exceeded 280 hours, and it was found that the effect of the coating layer could greatly improve the lifetime of the cathode material.
3.3 Transmission Electron microscope
The results of comparing the alloyed hafnium cathode cores and the metallic hafnium cathode cores used in examples 1 and 4 are shown in fig. 4(a) and (b), from which it can be seen that the crystal structure of alloyed hafnium is more complex and the lattice constant is smaller; in comparison, the lattice constant of pure hafnium is larger, the structure of the hafnium is beneficial to heat conduction, and the heat dissipation performance is more excellent, so that the performance of the hafnium is indirectly improved.
The foregoing are merely exemplary embodiments of the present invention, which enable those skilled in the art to understand or practice the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (10)
1. The cathode head of the plasma torch is characterized by comprising a cathode core, a hafnium carbide or zirconium carbide transition layer and a tantalum-hafnium-carbon alloy coating from inside to outside;
the cathode core is made of metal simple substance hafnium or hafnium alloy.
2. The cathode head according to claim 1, wherein the transition layer of hafnium carbide or zirconium carbide has a thickness of 1 to 15 μm.
3. The cathode head according to claim 1 or 2, wherein the tantalum hafnium carbon alloy coating has a thickness of 10 to 100 μm.
4. A preparation method of a plasma torch cathode head is characterized by comprising the following steps:
(1) spraying a transition layer material hafnium carbide or zirconium carbide on the surface of the cathode core;
(2) spraying a coating material of tantalum hafnium (Ta) with five carbon atoms on the surface obtained in the step (1)4HfC5)；
(3) And (3) sintering the obtained material in the step (2) to completely crystallize the transition layer material and the coating material.
5. The production method according to claim 4, wherein the plasma thermal spraying is adopted in the step (1), the powder feeding gas pressure is 0.55MPa to 0.75MPa, and the powder feeding rate is 35g/min to 45 g/min.
6. The production method according to claim 4 or 5, wherein the plasma thermal spraying is adopted in the step (2), the powder feeding gas pressure is 0.65MPa to 0.95MPa, and the powder feeding rate is 45g/min to 55 g/min.
7. The method according to claim 6, wherein the sintering temperature in step (3) is 800 ℃ to 1760 ℃, and sintering is stopped until the transition layer and the tantalum-hafnium-carbon alloy coating are completely crystallized.
8. The method according to claim 7, wherein the sintering temperature is 1300 ℃ to 1450 ℃.
9. The method according to any one of claims 4 to 8, wherein the surface of the cathode core does not include the contact surface of the cathode core and the base.
10. A plasma torch comprising the cathode head according to any one of claims 1 to 3.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011155686.3A CN114501763A (en) | 2020-10-26 | 2020-10-26 | Cathode head of plasma torch and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011155686.3A CN114501763A (en) | 2020-10-26 | 2020-10-26 | Cathode head of plasma torch and preparation method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114501763A true CN114501763A (en) | 2022-05-13 |
Family
ID=81470226
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011155686.3A Pending CN114501763A (en) | 2020-10-26 | 2020-10-26 | Cathode head of plasma torch and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114501763A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115745662A (en) * | 2022-11-14 | 2023-03-07 | 航天特种材料及工艺技术研究所 | High-bonding-strength hafnium-series ultrahigh-temperature ceramic coating and preparation method thereof |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0194634A2 (en) * | 1985-03-14 | 1986-09-17 | The Perkin-Elmer Corporation | Plasma gun nozzle with extended life |
| JPH10251846A (en) * | 1997-03-14 | 1998-09-22 | Ulvac Japan Ltd | Plasma generating hollow cathode |
| RU2239532C1 (en) * | 2003-07-16 | 2004-11-10 | Осинцев Григорий Владиславович | Electrode for plasma working |
| CN1777346A (en) * | 2004-11-15 | 2006-05-24 | K.C.科技股份有限公司 | Plama electrode structure,plasma source and plasma treatment device |
| CN102174704A (en) * | 2011-02-20 | 2011-09-07 | 中国船舶重工集团公司第七二五研究所 | Preparation method for tantalum-contained interlayer metallic oxide electrode |
| CN105491775A (en) * | 2015-12-29 | 2016-04-13 | 中国科学院力学研究所 | Method and device for improving running stability and prolonging service lifetime of arc plasma generator |
| CN205160897U (en) * | 2015-09-15 | 2016-04-13 | 中科华核电技术研究院有限公司 | A plasma generator for handling nuclear facilities solid waste |
| CN106793436A (en) * | 2016-12-16 | 2017-05-31 | 大连理工大学 | A kind of nickel nickel oxide magnesia composite cathode, preparation method and applications for strengthening atmospheric pressure plasma discharge intensity |
| CN109320302A (en) * | 2018-11-06 | 2019-02-12 | 航天特种材料及工艺技术研究所 | A kind of high-temperature oxidation resistant coating and preparation method thereof formed on basis material |
| CN109803479A (en) * | 2019-01-30 | 2019-05-24 | 武汉天和技术股份有限公司 | A kind of plasma flare point cathode structure and preparation method thereof |
| CN111593348A (en) * | 2020-06-23 | 2020-08-28 | 哈尔滨工业大学 | Metal surface thermal protection coating structure, preparation method thereof and composite material |
-
2020
- 2020-10-26 CN CN202011155686.3A patent/CN114501763A/en active Pending
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0194634A2 (en) * | 1985-03-14 | 1986-09-17 | The Perkin-Elmer Corporation | Plasma gun nozzle with extended life |
| JPH10251846A (en) * | 1997-03-14 | 1998-09-22 | Ulvac Japan Ltd | Plasma generating hollow cathode |
| RU2239532C1 (en) * | 2003-07-16 | 2004-11-10 | Осинцев Григорий Владиславович | Electrode for plasma working |
| CN1777346A (en) * | 2004-11-15 | 2006-05-24 | K.C.科技股份有限公司 | Plama electrode structure,plasma source and plasma treatment device |
| CN102174704A (en) * | 2011-02-20 | 2011-09-07 | 中国船舶重工集团公司第七二五研究所 | Preparation method for tantalum-contained interlayer metallic oxide electrode |
| CN205160897U (en) * | 2015-09-15 | 2016-04-13 | 中科华核电技术研究院有限公司 | A plasma generator for handling nuclear facilities solid waste |
| CN105491775A (en) * | 2015-12-29 | 2016-04-13 | 中国科学院力学研究所 | Method and device for improving running stability and prolonging service lifetime of arc plasma generator |
| CN106793436A (en) * | 2016-12-16 | 2017-05-31 | 大连理工大学 | A kind of nickel nickel oxide magnesia composite cathode, preparation method and applications for strengthening atmospheric pressure plasma discharge intensity |
| CN109320302A (en) * | 2018-11-06 | 2019-02-12 | 航天特种材料及工艺技术研究所 | A kind of high-temperature oxidation resistant coating and preparation method thereof formed on basis material |
| CN109803479A (en) * | 2019-01-30 | 2019-05-24 | 武汉天和技术股份有限公司 | A kind of plasma flare point cathode structure and preparation method thereof |
| CN111593348A (en) * | 2020-06-23 | 2020-08-28 | 哈尔滨工业大学 | Metal surface thermal protection coating structure, preparation method thereof and composite material |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115745662A (en) * | 2022-11-14 | 2023-03-07 | 航天特种材料及工艺技术研究所 | High-bonding-strength hafnium-series ultrahigh-temperature ceramic coating and preparation method thereof |
| CN115745662B (en) * | 2022-11-14 | 2023-08-22 | 航天特种材料及工艺技术研究所 | Hafnium-based ultrahigh-temperature ceramic coating with high bonding strength and preparation method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| WO2015151857A1 (en) | Plasma-resistant component, method for manufacturing plasma-resistant component, and film deposition device used to manufacture plasma-resistant component | |
| CN106825885B (en) | A kind of connection method of TZM alloy and WRe alloy under electric field-assisted | |
| WO2021004431A1 (en) | Technical method for printing similar structure of combustion chamber liner by using grcop-84 spherical powder | |
| WO2022095301A1 (en) | Diamond and preparation method and application thereof | |
| CN114501763A (en) | Cathode head of plasma torch and preparation method thereof | |
| JP4568094B2 (en) | Thermal barrier coating member and method for forming the same | |
| CN111508734B (en) | Method for producing copper-tungsten contact by electron beam infiltration | |
| CN112296492B (en) | Welding process method of dissimilar metal piece | |
| TWI738455B (en) | Method and product for processing electrostatic chuck using atomic layer deposition process, and operation method of plasma processing device | |
| JP2005281085A (en) | Crucible made of graphite | |
| Jiang et al. | Achieving high-efficiency electrically insulating ceramic layer formed on SiCp/Al composite by bipolar pulsed PEO for novel integrated strategy | |
| CN109483146B (en) | Method for repairing defects of titanium-aluminum intermetallic compound casting | |
| CN115007988B (en) | Copper alloy-steel composite cylindrical part and preparation method thereof | |
| WO2011061847A1 (en) | Electromagnetic casting apparatus for silicon | |
| TWI789542B (en) | Core wire holder, silicon manufacturing device, and silicon manufacturing method | |
| CN109175693B (en) | Single laser welding method for molybdenum plate | |
| KR20210011167A (en) | Coating method for sputtering apparatus of semiconductor manufacturing process and sputtering apparatus having coating by this method | |
| KR100855537B1 (en) | Method of forming plasma spray coating powder | |
| US20220359256A1 (en) | Method of manufacturing electrostatic chuck having electrode layer made of heterogeneous composite material, and electrostatic chuck manufactured thereby | |
| CN114525566B (en) | Surface micro-arc oxidation-high-temperature oxidation method for copper and copper alloy | |
| CN115121799A (en) | Plasma torch cathode and preparation method thereof | |
| JP3942441B2 (en) | Method for producing aluminum nitride | |
| CN113025962B (en) | Silicon-based porous anodic alumina template and preparation method thereof | |
| JP5781385B2 (en) | Degassing equipment dip tube | |
| CN111500888B (en) | Graphene composite metal material and preparation method and production equipment thereof |
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 |