CN1093119A - The manufacture method of tungsten-rhenium alloy galvanic couple filament - Google Patents
The manufacture method of tungsten-rhenium alloy galvanic couple filament Download PDFInfo
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- CN1093119A CN1093119A CN 94102602 CN94102602A CN1093119A CN 1093119 A CN1093119 A CN 1093119A CN 94102602 CN94102602 CN 94102602 CN 94102602 A CN94102602 A CN 94102602A CN 1093119 A CN1093119 A CN 1093119A
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Abstract
The present invention relates to make the method for high precision alloy threadlet by metal-powder.Mainly be applicable to the manufacturing of tungsten-rhenium alloy galvanic couple filament.It is characterized in that this method before batch mixing, earlier raw material powder is separated in separator; Batch mixing is to carry out in efficient blender, and also carries out the batch mixing second time after reduction is handled; Reduction under the hydrogen shield is handled and is divided three phases to carry out; Earlier under 1100～1300 ℃ of temperature, carry out presintering after being pressed into the base bar, under 2600～3000 ℃ of temperature, carry out high temperature incipient fusion sintering afterwards.Adopt the thermo wires of manufacturing of the present invention, the deviation of rhenium is little in its composition, and promptly composition is accurately even, and repdocutbility is good.
Description
The present invention relates to make the method for high precision alloy threadlet by metal-powder.Be specially adapted to the manufacturing of tungsten-rhenium alloy galvanic couple filament.
The tungsten rhenium alloy wire material can be measured up to 2000 ℃ as the galvanic couple material, even 2800 ℃ high temperature.
When replacing expensive platinum rhodium thermocouple to measure temperature, require temperature measurement accuracy must reach 0.5%t～0.25%t, just possess use value with Wolfram rhenium heat electric couple.
Requirement in accordance with regulations, the W-Re filament of φ 0.1mm, its pyroelecthc properties is in 1500～1800 ℃ of scopes, maximum allowable tolerance, 1554 ℃ of checks down, the first grade allowable tolerance is ± 6 ℃ (precision that is equivalent to 0.25%t), and seconds is ± 9 ℃ (being equivalent to the 0.5%t precision).For this reason, require the rhenium content in thermopair positive pole (W+3%Re), the negative pole (W+25%Re) very accurate, requirement in accordance with regulations, one-level thermo wires thermoelectric force ununiformity is checked under 1200 ℃ of temperature, and anodal permissible error is 40 μ V, and the negative pole permissible error is 30 μ V; The anodal permissible error of secondary thermo wires is 45 μ V, and negative pole is 35 μ V.And common anodal composition permissible error ± 0.3～0.5% that proposes, negative pole composition permissible error ± 0.5% can only obtain the thermopair that temperature measurement accuracy is 1%t.This also is the state of the art of tungsten-rhenium alloy galvanic couple in the prior art.
The temperature measurement accuracy of Wolfram rhenium heat electric couple depend on the thermo wires composition accurately, stable, and composition, physicals, weave construction are along thermo wires length direction distributing homogeneity two big key issues.It not only requires same alloy silk from first to last, but also requires the composition profiles between the different silk volumes all very even, requires physics, mechanical property and the weave construction of silk after final processing also to answer uniformity simultaneously.Could satisfy the requirement of high temperature measurement accuracy like this.
If need the temperature measurement accuracy of Wolfram rhenium heat electric couple to reach 0.25～0.5%t, the above-mentioned thermo wires of mentioning composition permissible error anodal and negative pole is not satisfy this requirement far away.That is to say the manufacture method of existing W-Re thermo wires, also be difficult to produce the thermo wires that is complementary with temperature measurement accuracy requirement 0.25～0.5%t.
In the prior art, the manufacture method of tungsten-rhenium alloy galvanic couple filament has following several:
1, solid-solid hybrid system
As tungsten powder-rhenium powder is mixed, after mixing, reduce processing.Can make alloying constituent reach better accuracy in this method, but homogeneity of ingredients is poor.
2, solid-liquid hybrid system
As tungsten powder is added in the rehenic acid ammonium solution, stir subsequently, heat, the rehenic acid crystalline ammonium is separated out, and then aftertreatment.
When this method is separated out in the crystallization of rehenic acid ammonium, the particle chap, just very inhomogeneous on the macroscopic view, and need further grind, mixing treatment, make the process complexity, mechanical loss is restive, causes inhomogeneous; In reduction process subsequently, the volatile loss of the compound of rhenium makes actual constituent off-design composition, thereby makes composition be difficult to accurate control in addition, is difficult to stablize (US3503720, clear 45-19567).
3, solution-solution mixed atomizing method
As with the soluble compounds solution of tungsten with after the soluble compounds solution of rhenium mixes, mixing solutions is carried out the spraying drying crystallization, and then carries out aftertreatment (US3623860).
The homogeneity of ingredients of this method is good, but that the concentration of solution is difficult to analyze exactly is definite, causes the poor accuracy of alloy component, simultaneously, because powder is thin, brings difficulty for technology subsequently.
Carry out homogenizing with above-mentioned four kinds of methods and handle the back and in hydrogen, reduce,, make the alloy preform bar, further swage, drawing, finally be processed into a material again through die mould, sintering.
In the aforesaid method, particularly in the liquid phase treating processes, complex process, composition is difficult to reach design requirements, and repdocutbility is poor; Other method is mixed also inhomogeneous, causes uneven components, during reduction, and the volatile loss of the compound of rhenium.Above-mentioned factor makes tungsten rhenium alloy wire not reach the requirement of the required coupling thermo wires of high precision measuring temperature.
The object of the present invention is to provide the manufacture method of even, the accurate stable tungsten-rhenium alloy galvanic couple filament of a kind of composition.
At above-mentioned purpose, the present invention has adopted following technical scheme:
The rehenic acid ammonium fine powder that raw material adopts tungsten powder and has the stable molecule formula; Both carry out separating treatment respectively before mixing in separator, powder is mixed under the situation of high dispersing again, reach the more even effect of microcosmic; Batch mixing is to carry out in efficient blender, and this efficient blender is not subjected to the influence of tungsten powder and ammonium rhenate powder specific gravity difference, makes to mix; Adopt basic, normal, high temperature three phases under hydrogen shield, to reduce subsequently, avoid generally in two stage reduction processes, the loss of rhenium content and cause the unsettled disadvantage of composition (because the degradation production Re of rehenic acid ammonium
2O
7, its fusing point and boiling point only are 297 ℃ and 363 ℃); In order further to make composition even, the powdered alloy after the reduction also needs further to mix in efficient blender; The alloy powder that mixes is pressed into the base bar, sinters alloy bar subsequently into, and swage, Wire Drawing becomes required silk material.
As known from the above, the technical process of tungsten-rhenium alloy galvanic couple filament manufacture method of the present invention is:
Raw material preparation-raw material separation-batch mixing-reduction batch mixing processing-the second time-die mould sintering-swage, drawing processing-finished product.
Now that each operation division is as follows:
1. raw material is prepared
Raw material is tungsten powder and ammonium rhenate powder, the granularity of tungsten powder≤4 μ m, the granularity of rehenic acid ammonium≤200 μ m.
2. raw material separates
Tungsten powder and ammonium rhenate powder are carried out separating treatment respectively in separator.The conglomeration particle is fully disperseed.
3. batch mixing
Tungsten powder that will separate through separator and the ammonium rhenate powder efficient blender of packing in the lump carries out batch mixing, mixing time 10～24 hours.
4. reduction is handled
The powdered alloy that mixes reduces processing under hydrogen shield.Reduction is handled and is divided three phases to carry out:
200～350 ℃ of first stage of reduction temperature, 1～2 hour time
400～600 ℃ of subordinate phase reduction temperatures, 1～2 hour time
700～900 ℃ of phase III reduction temperatures, 1～2 hour time
The treatment time in each stage is according to the treatment facility condition, furnace volume, charge amount and decide.
5. batch mixing for the second time
Powdered alloy after reduction is packed into once more and is mixed mixing time 8～20 hours in the efficient blender.
6. die mould sintering
Powdered alloy behind the second time batch mixing is pressed into the base bar; The base bar carries out presintering earlier under 1100～1300 ℃ of temperature and hydrogen shield; Time is 0.4～1 hour; Base bar through presintering carries out final incipient fusion sintering, 1～2 hour time under 2600～3000 ℃ of temperature and hydrogen shield.
7. forging rolling, drawing
Base bar behind the sintering is swaged on swager and is processed into thin rod, and thin rod is drawn into tungsten-rhenium alloy galvanic couple filament on drawing wire machine.
Adopt the tungsten-rhenium alloy galvanic couple filament of manufacturing of the present invention, its composition deviation reaches following index:
Deviation≤0.08% of anodal (3% rhenium+97% tungsten) rhenium
Deviation≤0.15% of negative pole (25% rhenium+75% tungsten) rhenium
The thermopair of forming with this galvanic couple silk coupling is used for thermometric, and its temperature measurement accuracy can reach 0.25～0.5%t level.
Compared with prior art, the present invention has following advantage and effect:
1. technology, equipment are simple, and mechanical loss is little.
2. made tungsten-rhenium alloy galvanic couple filament composition accurately evenly.
The repdocutbility of 3. made tungsten-rhenium alloy galvanic couple filament composition is good.
4. reduction temperature is low, and sintering character is good, and its density can reach more than 93% of theoretical density.
5. good processability.
In addition, the present invention also is equally applicable to composition profiles is required even dispersion and the preparations other powdered alloy goods that repdocutbility is good of height, as the preparation of cerium-tungsten alloy powder goods and thorium-tungsten alloy powder goods.
Embodiment one
According to method of the present invention, in the different time, prepared 12 batches of W-Re alloys powder, wherein galvanic couple positive pole, negative alloy powder are each 6 batches.With tungsten powder and ammonium rhenate powder is raw material, by anodal W+3%Re, negative pole W+25%Re prepare burden, tungsten powder particle-size≤4 μ m, rehenic acid ammonium granularity≤200 μ m, tungsten powder and ammonium rhenate powder are carried out separating treatment at first respectively in separator, add then to carry out batch mixing in the efficient blender; Mixed W-Re alloys powder carries out the reduction of three phases under hydrogen shield handles, and its reduction processing parameter is as shown in table 1; Alloy powder after the reduction carries out the batch mixing second time again.Behind the batch mixing, 12 batches of W-Re alloys material have been carried out the rhenium content deviation detected, its result is as shown in table 2.Simultaneously, get 8 samples respectively from different positions in a collection of positive and negative electrode W-Re alloys powder, rhenium content is also detected, detect the homogeneity with composition profiles in a collection of alloy material, its result is as shown in table 3.In addition, also detected different lot number W-Re alloys powder rhenium content deviation before and after reduction, as shown in table 4.
As known from Table 1, the W-Re alloys powder of the different lot numbers of different time preparation, the maximum deviation of rhenium content (weight %):
0.13%Re just very
Negative pole is 0.14%Re
Find out that by table 3 ununiformity of different sites content only is 0.02% in the same lot number W-Re alloys powder.
As seen from Table 4, it is still highly stable to adopt three phases reduction of the present invention to handle back rhenium content, and the positive and negative electrode maximum deviation is respectively 0.08%Re, 0.02%Re.
Embodiment two
According to method of the present invention, 4 batches of W-Re alloys powder galvanic couple silks (wherein anodal two batches, two batches at negative pole) have been manufactured experimently.Raw material still is tungsten powder and ammonium rhenate powder, tungsten powder particle-size≤4 μ m, and ammonium rhenate powder granularity≤200 μ m, two kinds of raw material powders carry out earlier separating treatment in separator; Prepare burden according to anodal W+3%Re, negative pole W+25%Re then, then add and carry out batch mixing in the efficient blender; Mixed W-Re alloys powder carries out the reduction of three phases under hydrogen shield handles; Alloy powder after the reduction is packed into and is carried out the second time in the efficient blender and mix.The reduction processing parameter of twice mixing time and three phases is as shown in table 5.To be pressed into the base bar through alloy powder behind the second time batch mixing, carry out presintering subsequently, then carry out final sintering; Base bar behind the sintering forges into thin rod on swager, then will thin rod be drawn into the galvanic couple silk on the machine connecing.Base bar size, twice sintering parameter are as shown in table 6.
Random sampling from 4 batches of galvanic couple silks, the deviation of mensuration rhenium content, its result is as shown in table 7.
In the galvanic couple silk of 4 batches of trial-productions, get the similar poles thermo wires and carry out the head and the tail cross-matched, and under 1500 ℃ of vacuum, survey the output potential that it mates thermo wires, and the size of this output potential is also represented the uneven components of this thermo wires W-Re alloys, its measuring result is as shown in table 8.Similar poles thermo wires head and the tail cross-matched is as follows:
A71/A72 A71/A82 A81/A82 A81/A72
B71/B72 B71/B82 B81/B82 B81/B72
(annotate: headed by the lot number odd number, even numbers is a tail)
As shown in Table 7, composition deviation positive pole only is 0.04% in the thermo wires, and negative pole only is 0.03%; Positive and negative total deviation between two batch of materials only is 0.04%.
As known from Table 8, the ununiformity positive pole of made tungsten-rhenium alloy galvanic couple filament under 1500 ℃ is 14 μ V to the maximum, and negative pole is 18 μ V to the maximum.
Description of drawings
Accompanying drawing 1,2 is respectively positive and negative electrode thermo wires along its length parasitic potential profile of detection under 1200 ℃.
Among Fig. 1,2, ordinate is parasitic electromotive force (μ V), and abscissa is a thermo wires sample length distance, and among Fig. 1,2, curve 1,2 is respectively the thermo wires sample that takes out from embodiment two lot number A7, B7; Curve the 3, the 4th, the positive and negative electrode sample of from commercially available same diameter tungsten-rhenium alloy galvanic couple filament, being got.Wherein, the measurement length of curve 1 is 100M(rice), the measurement length of curve 2 is 550M(rice), the measurement length of curve 3,4 is 5M(rice).
From Fig. 1,2 as can be known, adopt the anodal thermo wires of W-Re alloys that the present invention produced under 1200 ℃ of temperature, to detect 100 meters along its length, it sends the positive and negative total deviation of electromotive force only for≤25 μ V, and commercially available same thermo wires is under similarity condition, and then positive and negative total deviation is 65 μ V; Adopt the W-Re alloys negative pole thermo wires that the present invention produced, detect 550 meters along its length 1200 ℃ of temperature, it sends the positive and negative total deviation of electromotive force only is 20 μ V; And commercially available same W-Re alloys negative pole thermo wires, its positive and negative total deviation reaches 71 μ V.
Table 3, with rhenium content in a collection of positive and negative electrode W-Re alloys powder
The deviation of (weight %)
Table 6 embodiment two W-Re alloys base bar size and sintering parameters
Claims (3)
1, a kind of manufacture method of tungsten-rhenium alloy galvanic couple filament, its operation comprise raw material preparation, batch mixing, reduction processing, die mould sintering, forging rolling drawing; And with tungsten powder and ammonium rhenate powder is raw material, it is characterized in that:
1. before the batch mixing, tungsten powder and ammonium rhenate powder are carried out separating treatment respectively in separator;
2. batch mixing carries out in efficient blender;
3. the reduction under hydrogen shield is handled and is divided three phases to carry out:
200～350 ℃ of 1～2 hour times of first stage of reduction temperature
400～600 ℃ of 1～2 hour times of subordinate phase reduction temperature
700～900 ℃ of 1～2 hour times of phase III reduction temperature;
4. the W-Re alloys powder reinstalls and carries out the batch mixing second time in the efficient blender after reduction is handled;
5. the base bar of compacting carries out presintering earlier under 1100～1300 ℃ of temperature and hydrogen shield;
6. under 2600～3000 ℃ of temperature and hydrogen shield, carry out high temperature incipient fusion sintering through the base bar after the presintering.
2, method according to claim 1 is characterized in that the presintering time is 0.4～1 hour, and final incipient fusion sintering time is 1～2 hour.
3, according to the described method of claim 1, it is characterized in that the present invention also is applicable to even dispersion and the preparations other powdered alloy goods that repdocutbility is good of composition profiles requirement height, as the preparation of cerium-tungsten alloy powder goods and thorium-tungsten alloy powder goods.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 94102602 CN1029858C (en) | 1994-03-17 | 1994-03-17 | Producing method of tungsten-rhenium alloy galvanic couple filament |
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| CN 94102602 CN1029858C (en) | 1994-03-17 | 1994-03-17 | Producing method of tungsten-rhenium alloy galvanic couple filament |
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| CN1093119A true CN1093119A (en) | 1994-10-05 |
| CN1029858C CN1029858C (en) | 1995-09-27 |
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| CN 94102602 Expired - Lifetime CN1029858C (en) | 1994-03-17 | 1994-03-17 | Producing method of tungsten-rhenium alloy galvanic couple filament |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100338251C (en) * | 2004-05-11 | 2007-09-19 | 高殿斌 | Method for producing products of tungsten, molybdenum and alloy |
| CN102130288A (en) * | 2010-01-18 | 2011-07-20 | 重庆仪表材料研究所 | W10Re-W26Re tungsten-rhenium thermoelectric couple material and preparation method thereof |
| CN102586663A (en) * | 2012-04-05 | 2012-07-18 | 重庆材料研究院 | W3Re-W25Re thermocouple material and preparation method of thermocouple |
| CN105506429A (en) * | 2015-12-11 | 2016-04-20 | 重庆材料研究院有限公司 | Antioxidative tungsten-rhenium alloy for thermocouple and preparation method |
| CN106531599A (en) * | 2016-10-28 | 2017-03-22 | 安泰天龙钨钼科技有限公司 | Tungsten-rhenium-molybdenum alloy rotary anode target material for X-ray tube and preparation method thereof |
| CN108315624A (en) * | 2018-01-09 | 2018-07-24 | 安泰天龙钨钼科技有限公司 | A kind of High Performance W alloy bar material and preparation method thereof |
| CN110026561A (en) * | 2019-06-03 | 2019-07-19 | 无锡国涛钨铼合金科技有限公司 | A method of producing thermometric Wolfram rhenium heat electric couple silk with high reliability using combination technique |
| CN112126837A (en) * | 2020-08-19 | 2020-12-25 | 重庆材料研究院有限公司 | Preparation method of high-performance tungsten-rhenium alloy heating wire |
| CN113894289A (en) * | 2021-09-30 | 2022-01-07 | 合肥工业大学 | Preparation method of nano tungsten-rhenium powder with low oxygen content |
-
1994
- 1994-03-17 CN CN 94102602 patent/CN1029858C/en not_active Expired - Lifetime
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100338251C (en) * | 2004-05-11 | 2007-09-19 | 高殿斌 | Method for producing products of tungsten, molybdenum and alloy |
| CN102130288A (en) * | 2010-01-18 | 2011-07-20 | 重庆仪表材料研究所 | W10Re-W26Re tungsten-rhenium thermoelectric couple material and preparation method thereof |
| CN102130288B (en) * | 2010-01-18 | 2015-01-21 | 重庆仪表材料研究所 | W10Re-W26Re tungsten-rhenium thermoelectric couple material and preparation method thereof |
| CN102586663A (en) * | 2012-04-05 | 2012-07-18 | 重庆材料研究院 | W3Re-W25Re thermocouple material and preparation method of thermocouple |
| CN102586663B (en) * | 2012-04-05 | 2016-08-10 | 重庆材料研究院 | A kind of W3Re-W25Re thermocouple material and the method preparing thermocouple thereof |
| CN105506429A (en) * | 2015-12-11 | 2016-04-20 | 重庆材料研究院有限公司 | Antioxidative tungsten-rhenium alloy for thermocouple and preparation method |
| CN106531599A (en) * | 2016-10-28 | 2017-03-22 | 安泰天龙钨钼科技有限公司 | Tungsten-rhenium-molybdenum alloy rotary anode target material for X-ray tube and preparation method thereof |
| CN106531599B (en) * | 2016-10-28 | 2018-04-17 | 安泰天龙钨钼科技有限公司 | A kind of X-ray tube W-Re molybdenum alloy rotary anode target and preparation method thereof |
| CN108315624A (en) * | 2018-01-09 | 2018-07-24 | 安泰天龙钨钼科技有限公司 | A kind of High Performance W alloy bar material and preparation method thereof |
| CN110026561A (en) * | 2019-06-03 | 2019-07-19 | 无锡国涛钨铼合金科技有限公司 | A method of producing thermometric Wolfram rhenium heat electric couple silk with high reliability using combination technique |
| CN112126837A (en) * | 2020-08-19 | 2020-12-25 | 重庆材料研究院有限公司 | Preparation method of high-performance tungsten-rhenium alloy heating wire |
| CN113894289A (en) * | 2021-09-30 | 2022-01-07 | 合肥工业大学 | Preparation method of nano tungsten-rhenium powder with low oxygen content |
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| CN1029858C (en) | 1995-09-27 |
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