CN201043189Y - Hemicontinuous equipment for lot production of plasma surface metallurgy sheet material - Google Patents
Hemicontinuous equipment for lot production of plasma surface metallurgy sheet material Download PDFInfo
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- CN201043189Y CN201043189Y CNU2007200395459U CN200720039545U CN201043189Y CN 201043189 Y CN201043189 Y CN 201043189Y CN U2007200395459 U CNU2007200395459 U CN U2007200395459U CN 200720039545 U CN200720039545 U CN 200720039545U CN 201043189 Y CN201043189 Y CN 201043189Y
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- 239000002184 metal Substances 0.000 abstract description 12
- 229910052751 metal Inorganic materials 0.000 abstract description 12
- 238000010923 batch production Methods 0.000 abstract 1
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- 229910018487 Ni—Cr Inorganic materials 0.000 description 4
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- 229910052799 carbon Inorganic materials 0.000 description 3
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- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
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Abstract
The utility model provides a semi-continuous plasma surface metallurgy plate batch production device, which belongs to metal surface metallurgy field. Divided by production flow, the device comprises a forevacuum chamber (1), a double-layer glow plasma surface metallurgy chamber (2), a cooling chamber (3) and a workpiece drive mechanism. Wherein, a vacuum lock is arranged respectively between the forevacuum chamber (1) and the double-layer glow plasma surface metallurgy chamber (2), and between the double-layer glow plasma surface metallurgy chamber (2) and the cooling chamber (3). The workpiece drive mechanism in the double-layer glow plasma surface metallurgy chamber (2) is a shuttling drive mechanism (14). A clearance protection structure is arranged respectively between both sides of the shuttling drive mechanism (14) and workpieces. The width of the clearance is 0.5-2.0mm, and the depth of the clearance is 10-20mm. the device can realize the industrialized production requirement for the surface metallurgy of large area of metal plates.
Description
Technical field:
A kind of semi continuous plasma surface metallurgical plate is produced equipment in batches, belongs to the metal material surface metallurgical technology field.
Technical background:
The annual direct economic loss that causes owing to corrosion of metal of industrially developed country accounts for 2～4% of annual total value of production in national economy.Because of Serious Accidents such as corrosion causes catching fire, blast, bridge are caved in, air crash, nuclear reactor leakage happen occasionally, equipment and pipeline leak because of corrosion, make the poisonous and harmful material enter atmosphere, soil and water source.Adopt two kinds of methods to protect for metallic corrosion is general both at home and abroad, a kind ofly be to use whole corrosion-resistant material, stainless steel for example, another kind is to use the top coat technology.Yet Ni, Cr element account for very big proportion in the stainless material, and these alloy element resource shortage, exhausted day by day cause the price of stainless material high.Coating technology also is used widely in the surfacecti proteon of iron and steel, for example electroplate and electroless plating, but phenomenon usually appears peeling off in the firm binding force deficiency of coating and matrix when carry load.And the coating operation also brings problem of environmental pollution easily.For this reason, we adopt plasma surface metallurgical technology, prepare the Ni-Cr alloy layer at the plain carbon stool surface of steel plate, form a kind of low-cost plasma surface metallurgic steel plate suitable with the stainless steel plate corrosion resisting property.For realizing its large-scale commercial production, must the special-purpose equipment of producing of invention.
" double-deck glow plasma surface metallurgical technology " (US Patent 4520268,4731539) of Chinese scholar invention are provided with the source electrode of being made by desire co-diffusioning alloy element in a vacuum vessel in this technology, workpiece is a negative electrode, and the furnace wall is an anode; After applying certain bias voltage, produce glow discharge between source electrode and the negative electrode, by the metal ion stream bombardment metal plate and belt surface that source electrode sputters, heated parts, in workpiece surface deposition and infiltrate its inside, form surface alloying layer with specific physical, chemistry and mechanical property.By the surface alloy composition of layer distribution gradient of this technology acquisition, and do not have tangible boundary line between the matrix, thereby have bonding strength fully reliably.
Professor Xu Chong has invented furnace for double-layer metallic glow ion cementation (ZL87104626.1), and this equipment can be used for the production of small-sized component, and maximum accessible workpiece surface is long-pending to be 1m * 1m, for the practical application of double glow plasma surface alloying technique provides assurance.For surface-area greater than 2m
2Workpiece, also can't handle now, limited the large-scale industrial application of two brightness technology.
Summary of the invention:
The object of the present invention is to provide a kind of semi continuous plasma surface metallurgical plate to produce equipment in batches, to realize the suitability for industrialized production of large-area metal strip surface metallurgic.
A kind of semi continuous plasma surface metallurgical plate is produced equipment in batches, and it is characterized in that: it comprises prechamber, double-deck glow plasma surface metallurgic chamber and cooling room by Production Flow Chart, and the workpiece transmission rig; Wherein be provided with vacuum gate valve between prechamber and double-deck glow plasma surface metallurgic chamber, double-deck glow plasma surface metallurgic chamber and the cooling room; The indoor workpiece transmission rig of double-deck glow plasma surface metallurgic is the reciprocating motion type transmission rig, is provided with the gap protection structure between these reciprocating motion type transmission rig both sides and the workpiece, and gap width is the 0.5-2.0 millimeter, and gap depth is the 10-20 millimeter.
In the utility model, workpiece is made horizontal reciprocating movement by transmission rig with the speed of 0.1-1mm/s in that metallurgy is indoor, can guarantee the homogeneity of big area Metallurgical department science and engineering part surface composition.Be provided with the gap protection structure between transmission rig and the workpiece (negative electrode), can be used for stoping arc discharge (field causes discharge), guarantee workpiece surface quality.According to the geseous discharge theory, gap width is made as the 0.5-2.0 millimeter, and gap depth is made as the 10-20 millimeter.Simultaneously, be provided with heat-proof device, guarantee the homogeneity in temperature field in double-deck glow plasma surface metallurgic chamber.Above measure has guaranteed the production of continous-stable.Can produce the low-cost plasma surface metallurgic corrosion resistant plate of 4000-6000 ton per year through calculating equipment of the present invention.The plasma surface metallurgic corrosion resistant plate can partly replace stainless steel plate; reduce the use cost of Application Areas significantly, can satisfy departments such as thermal power station, Nuclear power plants, oil-gas mining, oil refining, chemical industry, chemical fertilizer, environmental protection, automobile, communications and transportation, water supply, light industry, medicine and Aeronautics and Astronautics steel plate solidity to corrosion, security and requirement on environmental protection.
Description of drawings:
Fig. 1: double-deck glow plasma surface metallurgic chamber schematic diagram.
Fig. 2: three-chamber type semi continuous plasma surface metallurgical plate of the present invention is produced the equipment configuration synoptic diagram in batches.
Fig. 3: two cell-type semi continuous plasma surface metallurgical plates of the present invention are produced the equipment configuration synoptic diagram in batches.
Fig. 4: plasma surface metallurgic corrosion resistant plate composition profiles figure.
Fig. 5: 0.05mol/L H
2SO
4Corrosive nature test result in the solution.
Number in the figure title: 1, pulse arc extinguishing power supply, 2, body of heater, 3, direct supply, 4, thermoscreen, 5, airing system, 6, workpiece (negative electrode), 7, source electrode, 8, vacuum system, 9, prechamber, 10, double-deck glow plasma surface metallurgic chamber, 11, cooling room, 12, vacuum gate valve, 13, vacuum gate valve, 14, transmission rig, 15, workpiece, 16, source electrode.
Embodiment:
As shown in Figure 1, be the principle of plasma surface metallurgic.Be provided with the source electrode 7 that alloying element is made in the vacuum vessel, workpiece 6 is a negative electrode, and furnace wall 2 is an anode.After by vacuum pump 8 furnace chamber being evacuated to the certain vacuum degree, the anti-Ar of filling is to operating air pressure and keep, and applies negative bias to source electrode and negative electrode respectively by two direct currents or the pulse power 1,3 then, produces hollow cathode glow discharge between source electrode and negative electrode.In order to guarantee the homogeneity in temperature field, be provided with thermoscreen 4 in the stove, also can increase an electric heating element in case of necessity.The alloy atom that sputters out in the source electrode adsorbs at workpiece surface, diffusion, thereby forms required alloy layer at workpiece surface.
As shown in Figure 2, produce the composition of equipment in batches for three-chamber type semi continuous plasma surface metallurgical plate of the present invention.It is made up of prechamber 9, double-deck glow plasma surface metallurgic chamber 10 and cooling room 11, be provided with vacuum gate valve 12 between prechamber and the double-deck glow plasma surface metallurgic chamber, be provided with vacuum gate valve 13 between double-deck glow plasma surface metallurgic chamber and the cooling room.
Be provided with one road float tolerance oil-sealed rotary pump in the prechamber 9, to guarantee the operating air pressure of 1.33-1333Pa.Also be provided with the workpiece transmission rig.Prechamber is provided with external heat source and air feed, exhaust system, can carry out vacuum or atmosphere protection heating to workpiece.
With reference to shown in Figure 1, metallurgical chamber 10 is provided with pulse arc extinguishing power supply 1, direct supply 3, thermoscreen 4, airing system 5, workpiece (negative electrode) 6, source electrode 7, vacuum system 8.Wherein vacuum system is provided with two shunt.Wherein main is the mechanical supercharging pumping set along separate routes, reaches 1.33-6.65Pa with the final vacuum that guarantees stove, and another is to adopt float tolerance mechanical pump along separate routes, to guarantee the operating air pressure of 1.33-1333Pa..Also be provided with the workpiece transmission rig in the metallurgical chamber 10, and it can realize horizontal reciprocating movement.
Cooling room 11 is provided with the workpiece transmission rig, also is provided with one road float tolerance oil-sealed rotary pump, to guarantee the operating air pressure of 1.33-1333Pa.Cooling room is provided with air feed, exhaust system, can carry out the atmosphere protection cooling to workpiece.
The principle of work of three cell structures is: with workpiece (metal sheet) prechamber of packing into, by the pre-heated work pieces of auxiliary thermal source to specified temperature; Open vacuum valve, by transmission rig workpiece is sent into the surface metallurgic chamber and carry out the surface alloying processing, prechamber is feeded again; After Alloying Treatment finishes, open the vacuum valve between surface metallurgic chamber and the cooling room, workpiece is delivered to the cooling room cooling; Repeat this process, realize semi-continuous production.
Utilize the present invention to carry out the method that continous way large-area metal sheet material plasma surface metallurgic is produced below in conjunction with Fig. 2 explanation.It is as follows to adopt this equipment special to carry out the operating process that the sheet metal surface metallurgic handles:
(1), pending workpiece is transported to prechamber and carries out the vacuum preheating;
(2), will be transported to double-deck glow plasma surface metallurgic chamber through the workpiece of preheating and handle, make workpiece make horizontal reciprocating movement in the treating processes in the indoor speed of double-deck glow plasma surface metallurgic with 0.1-1mm/s; Utilize the gap protection structure that is equipped with between transmission rig both sides and the workpiece to carry out arc extinguishing simultaneously, wherein gap width is the 0.5-2.0 millimeter, and gap depth is the 10-20 millimeter;
(3), will be transported to the cooling room cooling through the workpiece that surface metallurgic is handled;
(4) above-mentioned (1) step preheating procedure, (2) step surface metallurgic operation, (3) step refrigerating work procedure are the form of working continuously.
By changing source electrode material and processing parameter, above method can be used for carrying out at surface of steel plate the preparation of alloy layers such as wear-resisting, anti-corrosion, resistance to high temperature oxidation, has applicable surface widely.Such as: workpiece is the Q235 steel plate; Source electrode is the Ni80-Cr20 alloy sheets: source voltage 900-1100V, and workpiece voltage 400-700V, operating air pressure 30-80Pa, workpiece to-and-fro movement speed 0.1-1mm/s time 1-6 hour, temperature 800-1100 ℃, can prepare corrosion-resistant alloy layer.Such as: workpiece is 45 steel plates; Source electrode is the W50-Mo50 alloy sheets: source voltage 900-1200V, and workpiece voltage 400-700V, operating air pressure 30-80Pa, workpiece to-and-fro movement speed 0.1-1mm/s time 1-6 hour, temperature 800-1150 ℃, can prepare wear-resistant alloy layer etc.
Below for prepare a specific embodiment of Ni-Cr corrosion-resistant alloy layer at the plain carbon stool surface of steel plate.
1, workpiece is the Q235 steel plate; Source electrode is the Ni80-Cr20 alloy sheets: source voltage 1000V, workpiece voltage 600V, operating air pressure 45Pa, workpiece to-and-fro movement speed 0.5mm.
2, sheet metal is carried out the prechamber 9 of packing into after pickling and the activation treatment, be evacuated down to below the 10Pa, open thermal source, pre-heated work pieces (plain carbon stool steel plate) is to 800-1100 ℃.Double-deck glow plasma surface metallurgic chamber is evacuated down to the following final vacuum of 1Pa.
3, open vacuum gate valve 12 between prechamber 9 and the surface metallurgic chamber 10, workpiece is sent into surface metallurgic chamber 10 by transmission rig.Closing gate valve 12 is opened the fire door of prechamber 9, the new workpiece of packing into.
4, in the double-deck glow plasma surface metallurgic chamber 10, fill few Ar gas, make vacuum tightness reduce to 10-20Pa, apply cathode bias 100～300V, use the plasma bombardment cleaning workpiece.
5, strengthen the Ar flow, make operating air pressure rise to 20～80Pa, apply source electrode bias voltage 1000V, beginning alloying process.Adjusting source electrode and cathode current density make between sheet metal and the source electrode and produce hollow cathode effect, and the source electrode sputter is strengthened.The rising cathode voltage makes the workpiece temperature rising and maintains 1100 ℃ to 600V.Keep each processing parameter and carry out soaking time (being generally 1-5 hour) according to the processing requirement time according to processing requirement.
6, insulation is opened metallurgical chamber and cooling room vacuum gate valve after finishing, and workpiece is sent into the cooling room vacuum cooling.Open the vacuum gate valve between preheating chamber and the surface metallurgic chamber simultaneously, new workpiece is sent into the surface metallurgic chamber, repeating step 3-4.
7, workpiece is after the vacuum cooling chamber is cooled to below 200 ℃, closes the cooling room vacuum system and sheet metal is taken out.
8, repeat 1-6 and realize semi continuous production.
Experimental result and comparative analysis: the Q235 surface of steel plate prepares the Ni-Cr corrosion-resistant alloy layer, source electrode adopts nichrome sheet material to make, handled 2 hours down at 1000～1100 ℃, the thickness of Ni-Cr alloy layer can reach 50 μ m, surface composition (massfraction) is: Ni50～60%, alloy element concentration from outward appearance to inner essence reduces gradually in Cr15～20%, infiltration layer, with the matrix metallurgical binding.The composition profiles in steel plate cross section is seen Fig. 4, with the stainless corrosion resistance nature of 1Cr18Ni9Ti to such as Fig. 5, prove that its corrosion resistance nature of low-cost corrosion-resistant steel plate that present technique is produced surpasses the 1Cr18Ni9Ti austenitic stainless steel.
For reducing equipment cost, adapt to little drill shack operation, prechamber in three cell structures and cooling room can be merged, be simplified to two cell structure (see figure 3)s, principle be: with workpiece (metal sheet) prechamber of packing into, by the pre-heated work pieces of auxiliary thermal source to specified temperature; Open vacuum valve, by transmission rig workpiece is sent into the surface metallurgic chamber and carry out the surface alloying processing, prechamber is feeded again; After Alloying Treatment finishes, open the vacuum valve between surface metallurgic chamber and the cooling room, workpiece is delivered to the cooling room cooling; Repeat this process, realize semi-continuous production.
Claims (2)
1. a semi continuous plasma surface metallurgical plate is produced equipment in batches, and it is characterized in that: it comprises prechamber (1), double-deck glow plasma surface metallurgic chamber (2) and cooling room (3) by Production Flow Chart, and the workpiece transmission rig; Wherein be provided with vacuum gate valve between prechamber (1) and double-deck glow plasma surface metallurgic chamber (2), double-deck glow plasma surface metallurgic chamber (2) and the cooling room (3); The interior workpiece transmission rig in double-deck glow plasma surface metallurgic chamber (2) is reciprocating motion type transmission rig (14); be provided with the gap protection structure between these reciprocating motion type transmission rig (14) both sides and the workpiece; gap width is the 0.5-2.0 millimeter, and gap depth is the 10-20 millimeter.
2. semi continuous plasma surface metallurgical plate according to claim 1 is produced equipment in batches, and it is characterized in that: described vacuum chamber (1) and cooling room (3) are integrated.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2007200395459U CN201043189Y (en) | 2007-06-12 | 2007-06-12 | Hemicontinuous equipment for lot production of plasma surface metallurgy sheet material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2007200395459U CN201043189Y (en) | 2007-06-12 | 2007-06-12 | Hemicontinuous equipment for lot production of plasma surface metallurgy sheet material |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN201043189Y true CN201043189Y (en) | 2008-04-02 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNU2007200395459U Expired - Fee Related CN201043189Y (en) | 2007-06-12 | 2007-06-12 | Hemicontinuous equipment for lot production of plasma surface metallurgy sheet material |
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| Country | Link |
|---|---|
| CN (1) | CN201043189Y (en) |
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2007
- 2007-06-12 CN CNU2007200395459U patent/CN201043189Y/en not_active Expired - Fee Related
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| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20080402 Termination date: 20100612 |