CN102198507B - Method for producing tungsten bar serving as halogen tungsten lamp tungsten filament - Google Patents
Method for producing tungsten bar serving as halogen tungsten lamp tungsten filament Download PDFInfo
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- CN102198507B CN102198507B CN201110125548A CN201110125548A CN102198507B CN 102198507 B CN102198507 B CN 102198507B CN 201110125548 A CN201110125548 A CN 201110125548A CN 201110125548 A CN201110125548 A CN 201110125548A CN 102198507 B CN102198507 B CN 102198507B
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Abstract
The invention provides a method for producing a tungsten bar serving as a halogen tungsten lamp tungsten filament, comprising the following steps of: material selecting, pre-reducing, high potassium doping, reducing, acid rinsing, powder preparing, cold static pressure shaping, high temperature sintering and the like. Compared with the conventional technology, the method is characterized in that two crystal ammonium paratungstates are utilized to prepared raw materials, high potassium doping is adopted, preparation of middle granule tungsten powder is added, a powder distribution scheme is optimized by the middle granule tungsten and a unique incipient fusion high temperature sintering process is utilized. In the method, the granularity distribution of the tungsten powder avoids the peak or double peak phenomenon and has good normal distribution, after being sintered at high temperature, the cross section crystal of the tungsten bar is thin and uniform; the tungsten bar is pressed by a powder mixing scheme; according to a forming mechanism of potassium foams, the number of tungsten bar cross section crystal grains is increased; and the partial growth of the crystal grains is avoided so that the potassium foam is small in aperture, large in density, multiple in crystal boundary, long in line and uniform in distribution.
Description
Technical field
The present invention relates to the tungsten powder metallurgical technology, especially a kind of tungsten rod preparation method who is used to make the halogen tungsten lamp tungsten filament.
Background technology
Along with the fast development of Domestic Automotive Industry, electronics industry, space flight and aviation industry, the demand of halogen tungsten lamp is with the speed increment in every year 20%.Halogen tungsten lamp is mainly used in the illuminator of above-mentioned industry.There is the characteristic of shock and vibration in halogen tungsten lamp because of environment for use; Therefore require that its core material---the recrystallized structure of tungsten filament can form good dovetail bridging arrangement; Length-width ratio is greater than 12, and promptly elevated temperature strength is high under the high temperature burning-point state, and high temperature sink-resistance performance and anti-deformation are good.The technological process of production of tungsten filament is long; But after the process that changes sintered state (tungsten rod) from powdered form into is accomplished; The chemical composition of tungsten filament and structure property are established; Follow-up rolling processing is very small to the improvement and the castering action of tungsten filament high temperature sink-resistance performance, and therefore how obtaining the good high potassium tungsten rod of institutional framework becomes the key point that the wolfram filament for halogen tungsten lamp quality promotes.China's tungsten filament production technology is started late, and the domestic blank that still belongs to of the production line of wolfram filament for halogen tungsten lamp adopts common process, can only obtain low and middle-grade wolfram filament for halogen tungsten lamp through the production line screening of common tungsten filament, causes the yield rate of its product low, and production cost is high; This wolfram filament for halogen tungsten lamp is low because of its start-stop recrystallization temperature simultaneously, length-width ratio is little; Make that its elevated temperature strength is low, high temperature sink-resistance performance and anti-deformation is poor, service life short; Quality and external product gap are bigger, at present mainly through satisfying domestic demand from external high price import halogen tungsten lamp or wolfram filament for halogen tungsten lamp.Therefore, improve the tungsten rod quality, particularly urgent from improving the start with needs that satisfy the wolfram filament for halogen tungsten lamp quality of material property.
Summary of the invention
The object of the invention just provides a kind of tungsten rod preparation method who is used to make the halogen tungsten lamp tungsten filament, tungsten rod potassium content>=0.0085%, density>=17.20g/cm that this method of using prepares
3, grain size>=6000/mm
2, adopt existing routine techniques to carry out pressure processing, can produce the recrystallized structure structure and be good dovetail overlap joint; Length-width ratio is greater than 12; Steady quality, yield rate height, and elevated temperature strength is high under high temperature burning-point state, the wolfram filament for halogen tungsten lamp that high temperature sink-resistance performance and anti-deformation are good.
The tungsten rod preparation method who is used to make the halogen tungsten lamp tungsten filament of the present invention may further comprise the steps:
1, select materials, monocline ammonium paratungstate and spherical ammonium paratungstate are pressed the mixed of 3:1～1.5, are raw material with the amalgam of gained;
2, prereduction adopts routine techniques that above-mentioned raw materials is passed through four-tape warm area reduction furnace, and hydrogen reducing generation oxygen content is 20～20.5% blue tungsten oxide;
3, high potassium mixes; With common process the blue tungsten oxide wet method is mixed potassium silicate, aluminum nitrate solution; Potassium, silicon, aluminium are adsorbed in the blue tungsten hole, and potassium, silicon, aluminium content are respectively 0.18～0.20%, 0.30～0.35%, 0.010～0.013% in the doped blue tungsten;
4, reduction is used conventional reduction technology to generate Fisher particle size through secondary reduction doped blue tungsten and is the fine grained tungsten powder of 2.0～2.6 μ m, and is subsequent use; Use the direct once reduction of conventional reduction technology to generate Fisher particle size doped blue tungsten and be the coarse granule tungsten powder of 3.4～4.0 μ m, subsequent use; Adopting six band warm area reduction furnaces that doped blue tungsten is generated Fisher particle size through secondary reduction is the middle particle tungsten powder of 2.7～3.3 μ m; Subsequent use; In the process conditions of particle tungsten powder preparation be: once also the reason doped blue tungsten temperature for preparing tungsten dioxide is 530,550,580,620,650,670 ℃, and hydrogen flowing quantity is 2.0～3.0m
3/ h, dew point of hydrogen≤-60 ℃, boat charge is 300～350g/ boat; Push away speed and be the 25min/ boat; Output tungsten dioxide oxygen content is 12～14%, and the process conditions of particle tungsten powder in the secondary reduction preparation: temperature is 700,750,800,830,860,860 ℃, and hydrogen flowing quantity is 3.0～5.0m
3/ h, dew point of hydrogen≤-60 ℃, boat charge is 280～320g/ boat, pushes away speed and is the 30min/ boat;
5, pickling; With thin, in, to use concentration respectively be that superfluous adulterant and impurity are removed in 5～6% hydrochloric acid, 5～6% hydrofluoric acid washes to the coarse granule tungsten powder, the effective potassium content of gained acid-washed tungsten powder is respectively 0.016～0.018%, 0.012～0.014%, 0.008～0.010%;
6, join powder, thin, in, the coarse granule acid-washed tungsten powder mixes 25～30min by the weight ratio of 20～25:60～50:20～25 in batch mixer;
7, cold isostatic compaction; Adopting routine techniques that 2000g is cooperated the tungsten powder diameter of packing into is in the elasticity die sleeve of 23 ± 0.2mm, uses the cold isostatic press press forming, and the maximal pressure pressing pressure is 150～160MPa; Be shaped the back tungsten strip under hydrogen shield, through 1300 ± 50 ℃ of presintering 40～45min;
8, high temperature sintering; Under hydrogen shield; Tungsten strip directly energising heat-agglomerating in the incipient fusion machine after the presintering, sintering schedule is three sections intensification, two sections insulations, electric current/time parameter is intensification: (0-2000A)/5min, intensification: (2000-3800A)/15min, insulation: 3800A/15min, intensification: (3800-4900A)/2min, insulation: 4900A/20min; The crystallization of output tungsten rod section is tiny and even, potassium content>=0.0085%, density>=17.20g/cm
3, grain size>=6000/mm
2
The tungsten rod preparation method who is used to make the halogen tungsten lamp tungsten filament of the present invention; Distinguish preparation, the middle particle tungsten powder of the high potassium doping of the ammonium paratungstate mixed preparing, the employing that are two kinds of crystalline forms of raw material employing, newly-increased a kind of middle particle tungsten powder with common process and optimized the incipient fusion high temperature sintering system of joining powder scheme and employing uniqueness, its action principle and advantage are:
1, through the ammonium para-tungstate crystal pattern is influenced discovering of product performance; The crystalline form resulting a certain specific ammonium paratungstate of arranging in pairs or groups can make wolfram filament for halogen tungsten lamp each item performance all good; And the change of single crystalline form ammonium paratungstate ratio, the performance of gained tungsten filament changes thereupon;
2, the more conventional doping of blue tungsten doping of the present invention is high by 30～40%, and conventional method is if adopt the doping gained tungsten rod density of this method<17.0g/>cm
3, grain size<1000mm
2, be difficult to processing, yield rate is low, and cause the institutional framework deterioration, mould-crisp transition temperature height, problem such as high temperature sink-resistance performance difference.
3, the preparation of the newly-increased a kind of middle particle tungsten powder of the present invention, after the cooperation, the size distribution of tungsten powder has been avoided needle pattern or bimodal phenomenon, is good normal distribution, behind the high temperature sintering, makes the section crystallization of tungsten rod tiny and even.
4, by the tungsten strip that cooperates the compacting of powder scheme, when assurance is purified metals and obtained the well processed tissue, according to the formation mechanism of potassium bubble; The sintering current system heats up at a slow speed by beginning; Three sections intensifications, two sections INSULATION DESIGN to increase tungsten rod section number of die and to avoid the crystal grain part to grow up, reach that potassium abscess footpath is little, density is big, crystal boundary is many; Potassium bubble row are long, purpose is evenly distributed; And be good dovetail bridging arrangement through the pressure processing gained wolfram filament for halogen tungsten lamp recrystallized structure of tungsten rod, and length-width ratio >=12 of potassium bubble, the high temperature sink-resistance performance is good etc.
The specific embodiment
Embodiment one:
A kind of tungsten rod preparation method who is used to make the halogen tungsten lamp tungsten filament may further comprise the steps:
1, in the bipyramid batch mixer, mixes 20min in the 3:1.5 ratio with spherical ammonium paratungstate with the monocline ammonium paratungstate;
2, prereduction, through four-tape warm area reduction furnace, reduction generates blue tungsten oxide with above-mentioned raw materials;
3, the high potassium of blue tungsten mixes, and the 200kg blue tungsten oxide is added in the doping machine, and by blue tungsten weight, wet method is mixed 0.18% potassium, 0.32% silicon and 0.012% aluminium, after stirring, mixing, steam drying, obtains the blue tungsten of high potassium;
4, reduction; Fisher particle size is that the fine grained tungsten powder of 2.0～2.6 μ m and coarse granule tungsten powder that Fisher particle size is 3.4～4.0 μ m are by common process production; Fisher particle size is the middle particle tungsten powder manufacturing condition of 2.7～3.3 μ m: once also the reason doped blue tungsten temperature for preparing tungsten dioxide is 530,550,580,620,650,670 ℃, and hydrogen flowing quantity is 2.2m
3/ h, dew point of hydrogen are-72 ℃, and boat charge is the 302g/ boat, push away speed and are the 25min/ boat, and output tungsten dioxide oxygen content is 13.2%, and the temperature of particle tungsten powder is 700,750,800,830,860,860 ℃ in the secondary reduction preparation, and hydrogen flowing quantity is 3.80m
3/ h, dew point of hydrogen are-70 ℃, and boat charge is the 300g/ boat, push away speed and are the 30min/ boat, and the output tungsten powder particle-size is 3.05 μ m;
5, tungsten powder pickling, with thin, in, to use concentration respectively be that superfluous adulterant and impurity are removed in 5～6% hydrochloric acid, 5～6% hydrofluoric acid washes to the coarse granule tungsten powder;
6, thin, in, the coarse granule acid-washed tungsten powder fully mixes 30min by the weight ratio of 20:60:20 at " V " type batch mixer, cooperation powder potassium content is 0.0125%;
7, cooperate powder through cold isostatic compaction;
8, high temperature sintering, sintering current system (electric current/time) is pressed
(0-2000A)/5min+ (2000-3800A)/15min+3800A/15min+ (3800-4900A)/2min+4900A/20min carries out;
The potassium content of output tungsten rod is 0.0088%, density is 17.30g/cm
3, grain size is 6800/mm
2
Tungsten rod is through processing and follow-up conventional crin, filament processing technology to the finished product wolfram filament for halogen tungsten lamp of Φ 0.20mm of swaging, its tensile strength 0.81N/mg, tolerance+0.5%, coiling performance T type, and recrystallized structure is good dovetail bridging arrangement, and length-width ratio is 26.
Embodiment two:
A kind of tungsten rod preparation method who is used to make the halogen tungsten lamp tungsten filament may further comprise the steps:
1, in the bipyramid batch mixer, mixes 20min in the 3:1.2 ratio with spherical ammonium paratungstate with the monocline ammonium paratungstate;
2, prereduction, through four-tape warm area reduction furnace, reduction generates blue tungsten oxide with above-mentioned raw materials;
3, the high potassium of blue tungsten mixes, and the 200kg blue tungsten oxide is added in the doping machine, and by blue tungsten weight, wet method is mixed 0.2% potassium, 0.35% silicon and 0.013% aluminium, after stirring, mixing, steam drying, obtains the blue tungsten of high potassium;
4, reduction; Fisher particle size is that the fine grained tungsten powder of 2.0～2.6 μ m and coarse granule tungsten powder that Fisher particle size is 3.4～4.0 μ m are by common process production; In particle tungsten powder manufacturing condition: once also the reason doped blue tungsten temperature for preparing tungsten dioxide is 530,550,580,620,650,670 ℃, and hydrogen flowing quantity is 2.6m
3/ h, dew point of hydrogen are-68 ℃, and boat charge is the 322g/ boat, push away speed and are the 25min/ boat, and output tungsten dioxide oxygen content is 12.8%, and the temperature of particle tungsten powder is 700,750,800,830,860,860 ℃ in the secondary reduction preparation, and hydrogen flowing quantity is 4.30m
3/ h, dew point of hydrogen are-63 ℃, and boat charge is the 315g/ boat, push away speed and are the 30min/ boat, and the output tungsten powder particle-size is 3.21 μ m;
5, tungsten powder pickling, with thin, in, to use concentration respectively be that superfluous adulterant and impurity are removed in 5～6% hydrochloric acid, 5～6% hydrofluoric acid washes to the coarse granule tungsten powder;
6, thin, in, the coarse granule acid-washed tungsten powder fully mixes 30min by the weight ratio of 22:56:22 at " V " type batch mixer, cooperation powder potassium content is 0.0134%;
7, cooperate powder through cold isostatic compaction;
8, high temperature sintering, identical with embodiment one,
Output tungsten rod potassium content 0.0091%, density>=17.52g/cm
3, grain size>=6450/mm
2
Claims (1)
1. tungsten rod preparation method who is used to make the halogen tungsten lamp tungsten filament is characterized in that: may further comprise the steps:
(1), select materials, monocline ammonium paratungstate and spherical ammonium paratungstate are pressed the mixed of 3:1～1.5, are raw material with the amalgam of gained;
(2), prereduction, adopt routine techniques with above-mentioned raw materials through four-tape warm area reduction furnace, it is 20～20.5% blue tungsten oxide that hydrogen reducing generates oxygen content;
(3), high potassium mixes; With common process the blue tungsten oxide wet method is mixed potassium silicate, aluminum nitrate solution; Potassium, silicon, aluminium are adsorbed in the blue tungsten hole, and potassium, silicon, aluminium content are respectively 0.18～0.20%, 0.30～0.35%, 0.010～0.013% in the doped blue tungsten;
(4), reduction, use conventional reduction technology to generate Fisher particle size doped blue tungsten and be the fine grained tungsten powder of 2.0～2.6 μ m through secondary reduction, subsequent use; Use the direct once reduction of conventional reduction technology to generate Fisher particle size doped blue tungsten and be the coarse granule tungsten powder of 3.4～4.0 μ m, subsequent use;
Adopting six band warm area reduction furnaces that doped blue tungsten is generated Fisher particle size through secondary reduction is the middle particle tungsten powder of 2.7～3.3 μ m; Subsequent use; In the process conditions of particle tungsten powder preparation be: once also the reason doped blue tungsten temperature for preparing tungsten dioxide is 530,550,580,620,650,670 ℃, and hydrogen flowing quantity is 2.0～3.0m
3/ h, dew point of hydrogen≤-60 ℃, boat charge is 300～350g/ boat; Push away speed and be the 25min/ boat; Output tungsten dioxide oxygen content is 12～14%, and the process conditions of particle tungsten powder in the secondary reduction preparation: temperature is 700,750,800,830,860,860 ℃, and hydrogen flowing quantity is 3.0～5.0m
3/ h, dew point of hydrogen≤-60 ℃, boat charge is 280～320 g/ boats, pushes away speed and is the 30min/ boat;
(5), pickling, with thin, in, to use concentration respectively be that superfluous adulterant and impurity are removed in 5～6% hydrochloric acid, 5～6% hydrofluoric acid washes to the coarse granule tungsten powder;
(6), join powder, thin, in, the coarse granule acid-washed tungsten powder mixes 25～30min by the weight ratio of 20～25:60～50:20～25 in batch mixer;
(7), cold isostatic compaction; Adopting routine techniques that 2000g is cooperated the tungsten powder diameter of packing into is in the elasticity die sleeve of 23 ± 0.2mm; Use the cold isostatic press press forming; The maximal pressure pressing pressure is 150～160MPa, is shaped the back tungsten strip under hydrogen shield, through 1300 ± 50 ℃ of presintering 40～45min;
(8), high temperature sintering; Under hydrogen shield; Tungsten strip directly energising heat-agglomerating in the incipient fusion machine after the presintering; Sintering schedule is three sections intensifications, two sections insulations, and electric current/time parameter is for heating up: (0-2000A)/5min, intensification: (2000-3800A)/15min, insulation: 3800A/15min, intensification: (3800-4900A)/and 2min, insulation: 4900A/20min.
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| CN102672175B (en) * | 2012-05-15 | 2013-12-25 | 赣州海盛钨钼集团有限公司 | Preparation method of potassium-containing round-tungsten-doped aluminum strip |
| CN103056357A (en) * | 2012-11-28 | 2013-04-24 | 厦门虹鹭钨钼工业有限公司 | Method for preparing 5N purity tungsten bar or tungsten wire |
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| CN111790915B (en) * | 2020-03-03 | 2021-09-24 | 威海多晶钨钼科技有限公司 | Preparation method of potassium-doped superfine low-potassium tungsten powder |
| CN115074794B (en) * | 2022-05-13 | 2023-06-30 | 重庆材料研究院有限公司 | Preparation method of gold-plated tungsten wire for gas detector |
| CN116352100B (en) * | 2023-05-31 | 2023-07-28 | 赣州海盛钨业股份有限公司 | Production process of high-performance doped tungsten bar |
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| CN1052071A (en) * | 1989-11-28 | 1991-06-12 | 中南工业大学 | From ammonium tungstate solution, produce the method for fine and ultrafine tungsten powder |
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