CN102534290A - Platinum group metal alloy coating with controlled alloying elements and preparation method thereof - Google Patents
Platinum group metal alloy coating with controlled alloying elements and preparation method thereof Download PDFInfo
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- CN102534290A CN102534290A CN2012100553373A CN201210055337A CN102534290A CN 102534290 A CN102534290 A CN 102534290A CN 2012100553373 A CN2012100553373 A CN 2012100553373A CN 201210055337 A CN201210055337 A CN 201210055337A CN 102534290 A CN102534290 A CN 102534290A
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Abstract
The invention relates to a method for preparing a platinum group metal alloy coating on the surface of a refractory metal material; and in the coating, iridium or platinum are main components, zirconium, hafnium, tantalum, niobium and aluminium are alloying elements, and oxides of the alloying elements are enhancing components. The preparation method of the coating comprises the following steps of: taking a number of platinum group metal wires and alloying metal wires, and leading the platinum group metal wires and alloying metal wires to pass through aluminium oxide ceramics and be fixed, thereby forming an alloying target; and placing the target and a workpiece in a vacuum chamber, wherein one end of the target faces towards the workpiece, the other end of the target is connected with a power source, the platinum group metal wires are connected with a group of power sources in parallel, and the alloying metal wires can be connected with two to five groups of power sources according to the distributional design. The alloy coating is deposited in a vacuum furnace by adopting a double-glow plasma method; in the deposition process, the electricity of a part of the alloying elements can be cut off, the electricity can be supplied again after the electricity is cut off, and after the electricity is cut off, the connected alloying wires are in the non-working state and do not sputter alloying atoms or ions, and therefore, the content of the alloying elements in the coating can be adjusted.
Description
Technical field
The present invention relates to a kind of platinum group metal gold plating and preparation method thereof, especially relate to a kind of at controlled platinum group metal gold plating of the alloy element component on refractory material surface and preparation method thereof.
Background technology
Refractory metal has been widely used in various spacecrafts and engine material, and they have excellent hot strength, erosion resistance and performance such as high temperature resistant, but in the high temperature aerobic environment, can influence the work-ing life of material because of oxidation deactivation.Through adding alloying element or, being the necessary ways that overcome refractory metal high temperature oxidation stability difference at its surface preparation high-temperature oxidation resistant coating.The platinum metals has good anti-corrosion, high-temperature oxidation resistance, can adapt to the stress deformation that matrix plastoelastic deformation and high temperature creep cause.In the platinum metals, iridium and platinum have HMP, and the high-temperature oxidation resistance of good chemicalstability and excellence etc. be widely used as thermopair, thereby iridium and platinum can be used as high-temperature oxidation resistant coating protection refractory metal base material.Yet the platinum metals costs an arm and a leg usually, has limited the extensive application of iridium and platinum coating; In addition, at high temperature there is serious recrystallize in iridium and grows up phenomenon, causes crystal boundary to produce a large amount of micropores; Micropore becomes the passage of oxidizing atmosphere diffusion, causes the oxidation ablation of matrix refractory material.Add alloying element hafnium, zirconium, tantalum, aluminium etc.; Generate the characteristic of oxide compound by its oxidation; With the micropore that its expansible volume packing iridium metals produces, can bring into play iridium and platinum coating high-temp oxidation susceptibility, and help to stop the diffusion of matrix composition outside coating; Thereby remedy the deficiency of refractory metal high-temperature oxidation resistance, the advantage of performance refractory metal itself and platinum group metal gold plating.
Domestic have the related invention patent to platinum metals superalloy and coating; " a kind of iridium hafnium niobium high temperature alloy materials and preparation method thereof " (patent No.: ZL200510064747), " preparation method of iridium-aluminum high temperature oxidation resistance coating " (patent No.: ZL200910168837), " a kind of carbon material anti oxidation is with tungsten/tungsten/iridium composite coating layer and preparation method thereof " (patent No.: ZL200610041120), " a kind of preparation method of nano platinum oxidation coating for high temperature alloy " (patent No.: preparing method's patent of invention such as ZL200810058933) is arranged; These patents are consistent thinks that iridium, platinum and alloy thereof can be used as the ORC of refractory material; But the shortcoming of these methods comprises that preparation is complicated, and the associativity of coating and matrix is bad etc. under the high temperature." High-temperature diffusion barriers for protective coatings " (Surface and Coatings Technology; 2004; 188-189 153-157) points out in the paper, prepares Hf-Ni and Hf-Pt alloy coat through magnetron sputtering at the superalloy substrate surface; Alloy coat has high-temperature oxidation resistance, and can stop matrix element Cr, Re, Ta and W to the coating internal diffusion.USP " Ir-based alloys for ultra-high temperature the applications " (patent No.: point out US6982122) that iridium hafnium, iridium zirconium high-temperature alloy can be used as high-temperature oxidation resistant coating.The scholar (Behaviour of Ir-24at.%Ta films on Ni based single crystal superalloys) that waits of show utilizes magnetron sputtering technique or electro beam physics vapour deposition to prepare iridium tantalum, iridium hafnium and iridoplatinum coating in the Japan scholar village.At present; The technology of preparing of this coating mainly contains the plating codeposition, and electro beam physics vapour deposition is alloy target material or many targets codeposition, magnetron sputtering technique etc., and their advantage is that coating is fine and close; Shortcoming is that homogeneity of ingredients is poor, and the bonding strength between coating and the matrix is low.
Summary of the invention
The technical problem that the present invention will solve provides a kind of platinum group metal gold plating, it is characterized in that, the coated body element is platinum or iridium, and alloying element is zirconium, hafnium, tantalum, aluminium etc. but is not limited to this four kinds of alloying elements, and the oxide compound of alloying element such as ZrO
2, HfO
2, Ta
2O
5, Al
2O
3But be not limited to this four kinds of oxide compound enhancing ingredients.Alloying element in the coating can be a kind, also can be 2～3 kinds, and corresponding oxide compound can be a kind, also can be 2～3 kinds.Base material is a refractory material, can be molybdenum and alloy thereof, tungsten and alloy thereof, niobium and alloy thereof, wolfram varbide conductivity ceramics etc.This method can overcome that prior art floating coat bonding strength is low, coating contains impurity, there are shortcomings such as crackle in coating.
Another technical problem that the present invention will solve provides a kind of preparation method of platinum group metal gold plating, it is characterized in that with the platinum metals subassembly be target, and the refractory material of conduction is a body material, and body material also can be described as matrix, base material or workpiece.Target and base material are placed in the Vakuumkammer, and the target voltage range is at 800～1200V, and the base material voltage range uses rare gas element as work atmosphere at 300～600V.Connect direct supply, between target and base material, produce photoglow, through plasma sputtering bombardment target elements, form the platinum metal alloy coating through deposition and High temperature diffusion at substrate surface, made alloy coat thickness is 1 μ m～100 μ m.
The preparation method of platinum group metal gold plating provided by the invention is characterized in that comprising the step of following order:
(1) before the coating deposition, ultrasonic cleaning, oven dry are afterwards handled, polished and use respectively to matrix surface with abrasive paper for metallograph;
(2) distance between adjusting target and the matrix, interpole gap remains between 15～20mm;
(3) use mechanical pump to be evacuated to below the 5Pa, re-use molecular pump and be evacuated to highest attainable vacuum, open water coolant then;
(4) open shielding gas and be inflated to operating air pressure, make the interior operating air pressure of stove remain 15～55Pa, after the stable gas pressure, power-on slowly increases base material voltage;
(5) adjustment target voltage and base material voltage cause the sputter of target elements, begin to carry out the preparation of coating;
(6) behind the insulation certain hour, close source electrode and cathode power, stop air feed, closure molecule pump, mechanical pump are cooled to room temperature, close water coolant, take out base material.
Promptly in high temperature oxidation stability atmosphere, the alloy part element is at the corresponding oxide compound of the oxidized formation of high temperature in the base material use, and alloy part element and platinum metals form intermetallic compound.In the high low temperature of alternation, coating produces tiny crack, and the intermetallic compound oxidation that alloying element that oxidizing atmosphere is exposed with the unsalted surface in its crackle or alloying element and platinum metals form forms corresponding oxide compound once more.
The present invention discloses a kind of structure and installation method thereof of target simultaneously, it is characterized in that target is thread or strip, with the platinum metals silk; Especially platinum filament or iridium wire, alloying element silk, especially zirconium silk or hafnium filament; Be embedded on the sapphire discs; As penetrating shape, an end of silk is facing to base material, a termination energize.Corundum also can be a drum shape, and its interface can be a semicircle, also can be oval, and workpiece is placed in one, and the target silk is worn on it.The alloying element silk can connect by distribution design and be 2-5 group power supply, and the alloy silk quantity in every group can be different, and group can be different with the alloying constituent of organizing.Be coated with in the layer deposition process, the alloying element silk can partly cut off the power supply, and also adjustable low voltage also can be extracted from the top through shift mechanism, and the alloy silk that is connected is in off-position, can not sputter alloy atom or ion.Stop sputter, then reduced the quantity of sputter alloy silk, thereby can adjust the content of coating interalloy element, reach the effect that reduces coating interalloy element, make alloying element in the coating along the thickness direction Gradient distribution.Also can reduce the voltage of alloy silk, reduce its sputter amount, reduce the content of coating interalloy element.Switch on also can in the deposition process alloy silk that has cut off the power supply again, adjust coating interalloy constituent content at random.Also can design a kind of program, the voltage of alloy silk raises, reduces according to program repeat, thereby changes the regularity of distribution of coating interalloy element.
The invention has the advantages that: (1) composite target material controllable component, preparation is simple and be convenient to recycle.(2) the coating sedimentation rate is fast, and coat-thickness is easy to control, has improved the efficient of coating prepn; (3) matrix to curve form also can carry out the preparation of coating; (4) can obtain smooth, fine and close alloy coat; (6) has stronger bonding force between coating and the matrix.
Description of drawings
Fig. 1 is iridium or platinum composite target material and location of workpiece structural representation among the present invention.
Fig. 2 is the structural representation of deposition back alloy coat.
10 is the plain electrode of a combination gold dollar among the figure, and 20 are the plain electrode of another combination gold dollar, and 30 is the platinum group electrode, and 40 is sapphire discs, and 50 is the platinum metals silk, and 60 is the alloying element silk, and 70 is workpiece, and 80 is alloy coat.
Embodiment
Below in conjunction with embodiment the present invention is done further explain.
Embodiment 1
Embodiment 2
50,3 zirconium silks of 10 iridium wires and 3 hafnium filaments 60, passing corundum disk 40, one ends and niobium workpiece 70 distances is 19mm, 10,3 hafnium filaments of 3 zirconium wire connections of the other end power supply connect 20,10 iridium wires of power supply and connect power supply 30, feed argon gas after being evacuated to highest attainable vacuum.Setting and adopting the processing parameter of two brightness plasma technologies is 850V for target voltage, and base material voltage is 320V, operating air pressure 25Pa.Begin deposition, after the workpiece energising, connect all source electrode power supplys, depositing time was closed zirconium silk power supply 10 after 1 hour, deposit 1 hour again after, close hafnium filament power supply 20, deposit 1 hour again after, close all power supplys.Can obtain the thick alloy coat of 45 μ m after the deposition, from the top layer to the internal layer, be followed successively by iridium hafnium alloy layer, iridium zirconium alloy layer, iridium hafnium zirconium alloy layer.
Above-mentionedly be merely several embodiment of the present invention, but design concept of the present invention is not limited thereto, allly utilizes this design that the present invention is carried out the change of unsubstantiality, all should belong to the behavior of the scope of invading the present invention's protection.
Claims (9)
1. controlled platinum group metal gold plating of alloy element component on refractory material surface; It is characterized in that the coated body element is platinum or iridium; Alloying element is zirconium, hafnium, tantalum, aluminium etc. but is not limited to this four kinds of alloying elements, and the oxide compound of alloying element such as ZrO
2, HfO
2, Ta
2O
5, Al
2O
3But be not limited to this four kinds of oxide compound enhancing ingredients.
2. according to claims 1 described coating, the alloying element in the coating can be a kind, also can be 2～3 kinds, and corresponding oxide compound can be a kind, also can be 2～3 kinds.
3. the preparation method at the controlled platinum group metal gold plating of the alloy element component on refractory material surface is characterized in that with the platinum metals subassembly be target, and the refractory material of conduction is a body material; Body material also can be described as matrix, base material or workpiece; Target and base material are placed in the Vakuumkammer, and the target voltage range is at 800～1200V, and the base material voltage range is at 300～600V; Use rare gas element as work atmosphere; Connect direct supply, between target and base material, produce photoglow, through plasma sputtering bombardment target elements; Form the platinum metal alloy coating through deposition and High temperature diffusion at substrate surface, made alloy coat thickness is 1 μ m～100 μ m.
4. according to claims 3 described methods, it is characterized in that target is thread or strip, with platinum metals silk especially platinum filament or iridium wire; The alloying element silk is zirconium silk or hafnium filament especially, is embedded on the sapphire discs, as penetrates shape; One end of silk is facing to base material, a termination energize.
5. according to claims 3 described methods, it is characterized in that sapphire discs also can be a drum shape, its interface can be a semicircle, also can be oval, and workpiece is placed in one, and the target silk is worn on it.
6. according to claims 3 described methods, it is characterized in that it is 2-5 group power supply that the alloying element silk can connect by distribution design, the alloy silk quantity in every group can be different, and group can be different with the alloying constituent of organizing.
7. according to claims 3 described methods, it is characterized in that being coated with in the layer deposition process, the alloying element silk can partly cut off the power supply, and also adjustable low voltage, also can extract from the top through shift mechanism.
8. according to claims 3 described methods, it is characterized in that also can giving in the deposition process alloy silk that has cut off the power supply to switch on again, adjust coating interalloy constituent content at random.
9. according to claims 3 described methods, it is characterized in that also can designing a kind of program, the voltage of alloy silk raises, reduces according to program repeat, thereby changes the regularity of distribution of coating interalloy element.
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Cited By (11)
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|---|---|---|---|---|
| CN102899614A (en) * | 2012-07-16 | 2013-01-30 | 南京航空航天大学 | High temperature stable spark plug electrode coating and preparation method |
| CN103572210A (en) * | 2012-08-08 | 2014-02-12 | 苏州宏久航空防热材料科技有限公司 | High-temperature antioxidant iridium-based nano composite coating as well as preparation method thereof |
| CN103727317A (en) * | 2013-09-11 | 2014-04-16 | 太仓派欧技术咨询服务有限公司 | Manufacturing method of rhenium-based refractory metal hybrid tube |
| CN103738001A (en) * | 2013-09-11 | 2014-04-23 | 太仓派欧技术咨询服务有限公司 | Rhenium-based refractory metal hybrid material and structure thereof |
| CN104376952A (en) * | 2013-08-12 | 2015-02-25 | 苏州宏久航空防热材料科技有限公司 | Platinum-alloy-plated high-temperature alloy iron core |
| CN105734485A (en) * | 2016-04-19 | 2016-07-06 | 太原理工大学 | Preparation method of compound wear-resistant coating on surface of beryllium-copper alloy |
| CN108070859A (en) * | 2017-12-14 | 2018-05-25 | 西北有色金属研究院 | Refractory metal surfaces lamellar composite Ir/W high-temperature oxidation resistant coatings and preparation method thereof |
| CN109655521A (en) * | 2019-01-28 | 2019-04-19 | 中国地质科学院水文地质环境地质研究所 | Based on Accelerator mass spectrometry14The method for fast measuring of C |
| CN112921393A (en) * | 2021-01-22 | 2021-06-08 | 成都航宇超合金技术有限公司 | Single crystal alloy directional solidification method for reducing generation of mixed crystals and mould shell structure |
| CN114807709A (en) * | 2022-04-22 | 2022-07-29 | 昆明理工大学 | Rare noble metal niobium alloy gradient material and preparation method thereof |
| CN115707787A (en) * | 2021-08-20 | 2023-02-21 | 株式会社电装 | Iridium alloy |
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Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102899614A (en) * | 2012-07-16 | 2013-01-30 | 南京航空航天大学 | High temperature stable spark plug electrode coating and preparation method |
| CN103572210A (en) * | 2012-08-08 | 2014-02-12 | 苏州宏久航空防热材料科技有限公司 | High-temperature antioxidant iridium-based nano composite coating as well as preparation method thereof |
| CN104376952A (en) * | 2013-08-12 | 2015-02-25 | 苏州宏久航空防热材料科技有限公司 | Platinum-alloy-plated high-temperature alloy iron core |
| CN103727317A (en) * | 2013-09-11 | 2014-04-16 | 太仓派欧技术咨询服务有限公司 | Manufacturing method of rhenium-based refractory metal hybrid tube |
| CN103738001A (en) * | 2013-09-11 | 2014-04-23 | 太仓派欧技术咨询服务有限公司 | Rhenium-based refractory metal hybrid material and structure thereof |
| CN103738001B (en) * | 2013-09-11 | 2016-01-13 | 太仓派欧技术咨询服务有限公司 | A kind of rhenium base refractory metal hybrid materials and structure thereof |
| CN103727317B (en) * | 2013-09-11 | 2016-01-20 | 太仓派欧技术咨询服务有限公司 | A kind of rhenium base refractory metal mixes the preparation method of pipe |
| CN105734485B (en) * | 2016-04-19 | 2018-03-06 | 太原理工大学 | A kind of preparation method of beallon surface recombination wear-resistant coating |
| CN105734485A (en) * | 2016-04-19 | 2016-07-06 | 太原理工大学 | Preparation method of compound wear-resistant coating on surface of beryllium-copper alloy |
| CN108070859A (en) * | 2017-12-14 | 2018-05-25 | 西北有色金属研究院 | Refractory metal surfaces lamellar composite Ir/W high-temperature oxidation resistant coatings and preparation method thereof |
| CN109655521A (en) * | 2019-01-28 | 2019-04-19 | 中国地质科学院水文地质环境地质研究所 | Based on Accelerator mass spectrometry14The method for fast measuring of C |
| CN112921393A (en) * | 2021-01-22 | 2021-06-08 | 成都航宇超合金技术有限公司 | Single crystal alloy directional solidification method for reducing generation of mixed crystals and mould shell structure |
| CN115707787A (en) * | 2021-08-20 | 2023-02-21 | 株式会社电装 | Iridium alloy |
| CN115707787B (en) * | 2021-08-20 | 2024-01-12 | 株式会社电装 | Iridium alloy |
| CN114807709A (en) * | 2022-04-22 | 2022-07-29 | 昆明理工大学 | Rare noble metal niobium alloy gradient material and preparation method thereof |
| CN114807709B (en) * | 2022-04-22 | 2023-11-10 | 昆明理工大学 | Rare noble metal niobium alloy gradient material and preparation method thereof |
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Application publication date: 20120704 |