CN102784905B - Al-Ti-C-Er refiner and preparation method - Google Patents
Al-Ti-C-Er refiner and preparation method Download PDFInfo
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- CN102784905B CN102784905B CN201210189766.XA CN201210189766A CN102784905B CN 102784905 B CN102784905 B CN 102784905B CN 201210189766 A CN201210189766 A CN 201210189766A CN 102784905 B CN102784905 B CN 102784905B
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- titanium valve
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- 238000002360 preparation method Methods 0.000 title abstract description 14
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 46
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims abstract description 44
- 239000004411 aluminium Substances 0.000 claims abstract description 38
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 33
- 229910052719 titanium Inorganic materials 0.000 claims abstract description 17
- 238000007670 refining Methods 0.000 claims abstract description 16
- 229910045601 alloy Inorganic materials 0.000 claims abstract description 15
- 239000000956 alloy Substances 0.000 claims abstract description 15
- 238000006243 chemical reaction Methods 0.000 claims abstract description 15
- 238000003756 stirring Methods 0.000 claims abstract description 9
- 239000000155 melt Substances 0.000 claims abstract description 7
- 238000010438 heat treatment Methods 0.000 claims abstract description 5
- 238000002844 melting Methods 0.000 claims abstract description 4
- 230000008018 melting Effects 0.000 claims abstract description 4
- 238000002156 mixing Methods 0.000 claims abstract description 4
- 239000006025 fining agent Substances 0.000 claims description 29
- 239000000843 powder Substances 0.000 claims description 29
- 239000010936 titanium Substances 0.000 claims description 22
- 239000010439 graphite Substances 0.000 claims description 20
- 229910002804 graphite Inorganic materials 0.000 claims description 20
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 15
- 239000013078 crystal Substances 0.000 claims description 12
- 229910010038 TiAl Inorganic materials 0.000 claims description 11
- 239000003795 chemical substances by application Substances 0.000 claims description 10
- 239000002131 composite material Substances 0.000 claims description 7
- 238000000034 method Methods 0.000 claims description 7
- 229910052799 carbon Inorganic materials 0.000 claims description 5
- 238000004080 punching Methods 0.000 claims description 4
- 230000001680 brushing effect Effects 0.000 claims description 3
- 238000000576 coating method Methods 0.000 claims description 3
- 239000012535 impurity Substances 0.000 claims description 3
- 239000002994 raw material Substances 0.000 claims description 3
- 238000010792 warming Methods 0.000 claims description 2
- 239000011248 coating agent Substances 0.000 claims 1
- 239000002245 particle Substances 0.000 abstract description 23
- 229910052761 rare earth metal Inorganic materials 0.000 abstract description 18
- 150000002910 rare earth metals Chemical class 0.000 abstract description 12
- 239000000203 mixture Substances 0.000 abstract description 5
- 238000003825 pressing Methods 0.000 abstract 4
- 229910010039 TiAl3 Inorganic materials 0.000 abstract 1
- 229910001610 cryolite Inorganic materials 0.000 abstract 1
- VHHHONWQHHHLTI-UHFFFAOYSA-N hexachloroethane Chemical compound ClC(Cl)(Cl)C(Cl)(Cl)Cl VHHHONWQHHHLTI-UHFFFAOYSA-N 0.000 abstract 1
- 208000012868 Overgrowth Diseases 0.000 description 6
- 238000002485 combustion reaction Methods 0.000 description 3
- 229910000838 Al alloy Inorganic materials 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 238000007872 degassing Methods 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 238000004445 quantitative analysis Methods 0.000 description 2
- 239000002893 slag Substances 0.000 description 2
- 238000013019 agitation Methods 0.000 description 1
- 239000005030 aluminium foil Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 238000005056 compaction Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005204 segregation Methods 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000004781 supercooling Methods 0.000 description 1
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- Manufacture Of Metal Powder And Suspensions Thereof (AREA)
- Powder Metallurgy (AREA)
Abstract
The invention relates to an Al-Ti-C-Er refiner and a preparation method and belongs to the technical field of refiners. The Al-Ti-C-Er refiner comprises 3.0-10.0 wt% of Ti, 0.15-0.5 wt% of C, 0.1-0.3 wt% of Er and the balance of Al; the mass ratio of Ti to C is 17 to 22; and the phase of the refiner comprises alpha-Al, TiAl3, TiC, Al3Er, and AlErTi ternary phase. The preparation method comprises the following steps: uniformly mixing Ti, Al and graphite powder, placing the mixture in a mold, and pressing the mixture into blocks; heating and melting an aluminium ingot and covering cryolite; pressing in an Al-Er intermediate alloy and standing; and heating the melt to the required reaction temperature, pressing in the blocks, stirring for reaction, pressing in C2Cl6 for refining, slagging off and pouring. The Al-Ti-C-Er refiner solves the problem of difficult preparation of TiC particles, improves the wettability of C in Al by adding rare earth Er, and also improves the reaction efficiency.
Description
Technical field
The invention belongs to fining agent technical field, particularly a kind of aluminum alloy rare earth fining agent and preparation method.
Background technology
Adding grain refiner not only can refinement as cast condition crystal grain, and refinement arborescent structure can also reduce loosely, reduces hot cracking tendency, reduces casting flaw, improves follow-up processing characteristics.Along with the research to aluminium alloy fining agent, develop Al-Ti-C grain refiner in recent years.TiC particle size in Al-Ti-C grain refiner is little, is difficult for assembling, and is evenly distributed, and has the advantages such as good coherency with Al, and be subject to extensive concern.Because the wetability of C in Al is poor, prepare very difficultly, by strong agitation or pyroreaction, prepare Al-Ti-C grain refiner, increased preparation cost, limited the extensive use of Al-Ti-C grain refiner.Rare earth element is surface reactive material, adds the surface energy that reduces aluminium in aluminum melt to; Rare earth can crystal grain thinning and arborescent structure: rare earth element is easily adsorbed on crystal boundary and phase boundary place, hinders growing up of crystal grain; Rare earth element segregation coefficient is larger, easily forms larger constitutional supercooling.Numerous refinement advantages and metamorphism thereof based on rare earth, in the process of preparation Al-Ti-C grain refiner, add rare earth element, can improve the wetability of C in aluminium, thereby improve reaction efficiency, and preparation is fining agent more efficiently.
Summary of the invention
The present invention adopts self-overgrowth reaction process, adds the rare earth Er of different content, develops a kind of efficient, long-acting, clean Al-Ti-C-Er composite modifying-refining agent.
For addressing the above problem, this patent main technical schemes is: add the rare earth Er of different content, prepare a kind of composite modifying-refining agent.
An Al-Ti-C-Er composite modifying-refining agent, comprises following mass percent component, Ti:3.0-10.0wt%, and C:0.15-0.5wt%, Er:0.1-0.3wt%, surplus is Al; Mass ratio=16-22(of Ti/C preferably 50/3), fining agent thing comprises α-Al, TiAl mutually
3, TiC, Al
3er, AlErTi ternary equate.In fining agent, TiC particle size, below 0.5 μ m, is uniformly distributed and is spherical; TiAl
3below particle 10um, be uniformly distributed, and become block, its grain refining efficiency is apparently higher than traditional Al-Ti-C fining agent, and has metamorphism.
The preparation method of above-mentioned composite modifying-refining agent, is characterized in that Er adds with intermediate alloy form, and Ti and C add so that simple substance is Powdered, adopt self-overgrowth reaction process preparation, specifically comprise the following steps:
(1) raw material is prepared, and weighs on request graphite powder, titanium valve, aluminium powder, Al-Er intermediate alloy, aluminium ingot, and the mass ratio that requires titanium valve and graphite powder is 16-22, and aluminium powder accounts for graphite powder, titanium valve and the more than 40% of aluminium powder gross mass, aluminium ingot purity 99.9%;
(2) titanium valve, aluminium powder, powdered graphite are mixed, the powder mixing is placed in to mould, be pressed into block;
(3) utilize well formula resistance furnace that aluminium ingot is heated to 780-800 ℃, treat that aluminium ingot melts completely, cover one deck ice crystal coverture; Graphite bell jar is pressed into Al-Er intermediate alloy, standing, until intermediate alloy melts completely and spreads evenly; Again melt is warming up to 800-900 ℃, graphite bell jar is pressed into the block of step (2), graphite rod uniform stirring, reaction 10min; After having reacted, standing 5min, is pressed into C
2cl
6refining, skims, and aluminum melt is poured in the punching block of 250 ℃ of preheatings, obtains Al-Ti-C-Er modifying-refining agent.
Above-mentioned preferred ice crystal and C
2cl
6at 100 ℃ of heating 1h, remove moisture; By instrument brushing one coatings such as mould and the spoons of skimming, prevent that Fe impurity element from polluting fining agent.Select graphite crucible to carry out melting, graphite rod stirs, and prevents the pollution of Si.
Titanium valve 325 orders, graphite powder 300 orders.Aluminium powder accounts for graphite powder, titanium valve and the more than 40% of aluminium powder gross mass, mixes briquet.
Aluminum melt reaches uniform temperature, is pressed into powder agglomates, and uniform stirring makes it that combustion reaction occur.
The invention solves TiC and prepare difficult problem, the interpolation of rare earth Er, the wetability of the C of raising in Al, has improved reaction efficiency.Reduced TiAl in fining agent
3, TiC particle size, improved its pattern and distribution, improved refinement efficiency, be a kind of stable, long-acting, efficient, clean Al-Ti-C-Er composite modifying-refining agent.
Accompanying drawing explanation
Fig. 1 is the metallograph of the fining agent prepared of 850 ℃ of self-overgrowth reaction process;
Wherein: a embodiment 1 adds 0.2Er; B comparative example is not added rare earth Er element;
Fig. 2 is the SEM figure of Al-5Ti-0.3C-0.2Er fining agent;
Fig. 3 is the thing phase quantitative analysis of Al-5Ti-0.3C-0.2Er fining agent.
The specific embodiment
Embodiment 1
It is as follows that self-overgrowth reaction process is prepared Al-5Ti-0.3C-0.2Er fining agent process:
1. raw material is prepared, and fining agent is by aluminium ingot, aluminium powder, titanium valve, graphite powder, Al-Er intermediate alloy, C
2cl
6prepare with ice crystal coverture.Wherein aluminium ingot purity 99.9%, powder size, Ti powder 325 orders, C powder 300 orders.
2. the fining agent of preparation 1Kg, weighs graphite powder, titanium valve, aluminium powder, Al-Er intermediate alloy, aluminium ingot on request, and aluminium burn out rate is 3%.Require Ti/C=50/3(wt%); The 60%(aluminium powder quality that powder accounts for powder agglomates quality is 78g).
3. titanium valve, aluminium powder, powdered graphite are mixed, the powder mixing is placed in to mould, apply the pressure of 10MPa, be pressed into the cylindricality powder agglomates of φ 40 * 50.
4. ice crystal and C
2cl
6at 100 ℃ of heating 1h, remove moisture.
5. by instrument brushing one coatings such as mould and the spoons of skimming, prevent that Fe impurity element from polluting fining agent.Select graphite crucible to carry out melting, graphite rod stirs, and prevents the pollution of Si.
6. utilize well formula resistance furnace that clean aluminium ingot is heated to 780 ℃, treat that aluminium ingot melts completely, cover one deck ice crystal, prevent the oxidation of aluminium and air-breathing; First Al-Er intermediate alloy is wrapped with aluminium foil, graphite bell jar is pressed into aluminium liquid, and standing 5min treats that intermediate alloy dissolves completely, and Er diffusion evenly; Furnace temperature is risen to 850 ℃ again, graphite bell jar is pressed into aluminum melt by the cylindricality powder agglomates suppressing in advance, and graphite rod uniform stirring makes it that combustion reaction occur, reaction 10min; The C that adds 3%wt
2cl
6carry out refining degasification, standing 5min; With skimming, spoon removes surperficial slag and oxide skin; Treat that temperature reduces to 720 ℃, be poured in 250 ℃ of punching blocks of preheating, obtain Al-5Ti-0.3C-0.2Er modifying-refining agent.The fining agent that this legal system is standby, particle size is little, and is evenly distributed.
Comparative example
Self-overgrowth reaction process is prepared Al-5Ti-0.3C fining agent
Will be by aluminium ingot, aluminium powder, titanium valve, graphite powder by composition requirement proportioning.Powder compaction becomes the cylindricality powder agglomates of φ 40 * 50 on request.
Utilize well formula resistance furnace that clean aluminium ingot is heated to 780 ℃, treat that aluminium ingot melts completely, cover one deck ice crystal, prevent the oxidation of aluminium and air-breathing; Furnace temperature is risen to 850 ℃, and graphite bell jar is pressed into aluminum melt by the cylindricality powder agglomates suppressing in advance, and graphite rod uniform stirring makes it that combustion reaction occur, reaction 10min; The C that adds 3%wt
2cl
6carry out refining degasification, standing 5min; With skimming, spoon removes surperficial slag and oxide skin; Treat that temperature reduces to 720 ℃, be poured in 250 ℃ of punching blocks of preheating, obtain Al-5Ti-0.3C fining agent.
The Al-5Ti-0.3C-0.2Er that Fig. 1 adopts self-overgrowth reaction process to prepare, the metallograph of Al-5Ti-0.3C fining agent.Figure a, b are respectively Al-5Ti-0.3C-0.2Er, Al-5Ti-0.3C metallograph, and in figure, size block particle below 10 μ m is TiAl
3particle; Size is below 0.5 μ m, and the particle distributing is in the form of sheets TiC particle.Add rare earth element and promoted TiC, TiAl
3the formation of particle, TiC particle, TiAl
3number of particles showed increased, and disperse distributes.Rare earth has also obviously improved the pattern of particle, in intermediate alloy prepared by interpolation rare earth, and block TiAl
3it is block that particle becomes substantially, suppressed TiAl
3growing up of particle; Do not add the intermediate alloy of rare earth, its TiAl
3particle is needle-like, has occurred to grow up, and is unfavorable for thinning effect.
Fig. 2 is the SEM figure of the Al-5Ti-0.3C-0.2Er fining agent of embodiment 1 preparation, sees a large amount of blocky particles from figure, the small-particle that sheet distributes, and a kind of contrast is brighter, is AlErTi, Al3Er; A kind of contrast is darker, is TiC.These two kinds of mix particles together, show that rare earth element can be good at suppressing the gathering of TiC particle, make its distribution more even.
Fig. 3 is the thing phase quantitative analysis of the Al-5Ti-0.3C-0.2Er fining agent of embodiment 1 preparation, can find out that fining agent is mainly by α-Al, TiAl
3, the phase composition such as TiC, AlErTi.Literature research shows to add rare earth Er in Al can form Al
3er, owing to having added 0.2% Er in fining agent, and has formed more AlErTi phase, Al
3er content will reduce, and its contrast is mutually basic identical with AlErTi, cannot distinguish.TiC particle size is less, and power spectrum fails well to analyze.Fining agent adds in the alloy of wanting refinement, and AlErTi will decompose, and discharges Er atom, increases the wetability of TiC and Al, makes the difficulty of the motion change of particle, and fining agent is more long-acting.
Claims (5)
1. a method of preparing Al-Ti-C-Er composite modifying-refining agent, Al-Ti-C-Er composite modifying-refining agent comprises following mass percent component, Ti:3.0-10.0wt%, C:0.15-0.5wt%, Er:0.1-0.3wt%, surplus is Al; Mass ratio=16-22 of Ti/C, fining agent thing comprises α-Al, TiAl mutually
3, TiC, Al
3er, AlErTi ternary phase; It is characterized in that, comprise the following steps:
(1) raw material is prepared, and weighs on request graphite powder, titanium valve, aluminium powder, Al-Er intermediate alloy, aluminium ingot, and the mass ratio that requires titanium valve and graphite powder is 17-22, and aluminium powder accounts for graphite powder, titanium valve and the more than 40% of aluminium powder gross mass, aluminium ingot purity 99.9%;
(2) titanium valve, aluminium powder, powdered graphite are mixed, the powder mixing is placed in to mould, be pressed into block;
(3) utilize well formula resistance furnace that aluminium ingot is heated to 780-800 ℃, treat that aluminium ingot melts completely, cover one deck ice crystal coverture; Graphite bell jar is pressed into Al-Er intermediate alloy, standing, until intermediate alloy melts completely and spreads evenly; Again melt is warming up to 800-900 ℃, graphite bell jar is pressed into the block of step (2), graphite rod uniform stirring, reaction 10min; After having reacted, standing 5min, is pressed into C
2cl
6refining, skims, and aluminum melt is poured in the punching block of 250 ℃ of preheatings, obtains Al-Ti-C-Er modifying-refining agent.
2. according to the method for claim 1, it is characterized in that ice crystal and C
2cl
6at 100 ℃ of heating 1h, remove moisture.
3. according to the method for claim 1, it is characterized in that, by mould and spoonful instrument brushing one coating of skimming, prevent that Fe impurity element from polluting fining agent.
4. according to the method for claim 1, it is characterized in that, select graphite crucible to carry out melting, graphite rod stirs, and prevents the pollution of Si.
5. according to the method for claim 1, it is characterized in that titanium valve 325 orders, graphite powder 300 orders.
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| CN201210189766.XA CN102784905B (en) | 2012-06-08 | 2012-06-08 | Al-Ti-C-Er refiner and preparation method |
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| CN201210189766.XA CN102784905B (en) | 2012-06-08 | 2012-06-08 | Al-Ti-C-Er refiner and preparation method |
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| CN102784905B true CN102784905B (en) | 2014-04-16 |
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|---|---|---|---|---|
| CN108277373A (en) * | 2018-02-07 | 2018-07-13 | 兰州理工大学 | A kind of Al-Ti-C-La alloys and preparation method thereof |
| CN112404374B (en) * | 2020-11-30 | 2022-05-31 | 中国科学院金属研究所 | Preparation method and application of refiner |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA1331519C (en) * | 1989-05-03 | 1994-08-23 | Alcan International Limited | Production of an aluminum grain refiner |
| CN100383268C (en) * | 2005-10-21 | 2008-04-23 | 兰州理工大学 | Prepn process of composite Al-Ti-C grain refining agent for aluminium and aluminium alloy |
| CN1789448A (en) * | 2005-11-28 | 2006-06-21 | 大连理工大学 | Grain refiner for synthesis of aluminium alloy by laser ignited self-propagation and method for preparing the same |
| CN100491561C (en) * | 2006-04-25 | 2009-05-27 | 清华大学 | Aluminum-titanium-boron rare earth fining agent, and its preparing method |
| CN100436615C (en) * | 2007-05-26 | 2008-11-26 | 太原理工大学 | Aluminum-titanium-carbon-yttrium intermediate alloy and preparing method thereof |
| CN101608270B (en) * | 2009-07-27 | 2011-01-05 | 福州大学 | Refiner of aluminium and aluminium alloy with high efficiency and low cost, and preparation method thereof |
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