CN1810419A - Prepn process of composite aluminium/alumina material with alumina coated metal aluminium - Google Patents
Prepn process of composite aluminium/alumina material with alumina coated metal aluminium Download PDFInfo
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- CN1810419A CN1810419A CN 200610024249 CN200610024249A CN1810419A CN 1810419 A CN1810419 A CN 1810419A CN 200610024249 CN200610024249 CN 200610024249 CN 200610024249 A CN200610024249 A CN 200610024249A CN 1810419 A CN1810419 A CN 1810419A
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Abstract
The present invention provides one method of preparing composite Al/Al2O3 cermet material, and features that Al2O3 coated Al powder used as the second phase and Al2O3 produced through large scale industrial production are ball milled, mixed, hot pressed and sintered to obtain the composite Al/Al2O3 material, where, Al2O3 coated Al powder plays important role of improving the distribution homogeneity of metal phase inside ceramic base, reducing the oxidation of metal Al and improving the comprehensive performance of the composite material. Compared with available preparing process, the process of the present invention can obtain composite material with homogeneous distribution of two phases and greatly raised bending strength and breaking toughness.
Description
Technical field
The present invention relates to Al/Al with aluminium oxide parcel aluminium
2O
3The preparation method of ceramic-metal composite, principal character are that metal phase Al is with Al
2O
3The form of the composite granule of parcel Al is introduced.Belong to field of compound material.
Background technology
Al
2O
3Be one of most widely used structural ceramic material, it has higher-strength, high rigidity, low-density, performance such as corrosion-resistant, wear-resistant.Yet the greatest weakness of pottery is also arranged simultaneously, is exactly that toughness is very poor, when being subjected to unexpected contact overload or violent variations in temperature, being easy to crack and causing the failure damage of structure member.In ceramic phase, evenly disperse the metal of toughness to constitute the effective ways that composite is a ceramic toughening mutually.
To discovering of the interface energy relation of a lot of metals and pottery: because the difference on metal and the ceramic of bonding under general condition is difficult to realize making melt metal finely wetting to ceramic phase.On the structural design of material, pursue more again simultaneously the metal phase continuously, this can't be avoided having the oxidation of the metal phase of continuous structure undoubtedly.And the isolated island shape metal phase of reunion sees it is that the utmost point is dispersed in the ceramic phase unevenly from less yardstick, and such microstructure does not obviously have possibility to improve the fragility of ceramic material.Avoid the oxidation and the gathering of metal phase, just it must be protected.Face coat, surface modification or metal is imbedded in ceramic phase mutually in the middle of perhaps be a desirable approach.(Guo Jingkun, the investigation of materials journal, 2000,14,123-126) in recent years, the research that packing technology is used to prepare equal phase ceramics has obtained certain progress.(Rui Zhang, LianGao, Jingkun Guo, Journal of the American Ceramic Society, Vol.86 (2003), No.8, pp.1446-1448; Myung-Beom Park, Nam-Hee Cho, Chung-Don Kim, Sang-Kyun Lee, Journal of the American Ceramic Society, Vol.87 (2004), No.3, pp.510-512) it has not only improved biscuit density and sintering activity, also improves the mechanical property of out of phase uniformity and sintered body.The inventor has synthesized Al/Al in early stage with wet chemistry method
2O
3Nuclear-shell compound particle (Huamin Kou, Jing Wang, Yubai Pan, Jingkun Guo, Key EngineeringMtaerials (2006) Vol.313 attempts the Al/Al that has package structure with this on basis pp.63-68)
2O
3Composite granule adds Al to
2O
3In the ceramic matrix, be about to die design and the crystal boundary design formation compound particle that combines together, this not only can effectively be avoided the agglomeration traits of single particle, realize two alternate even dispersions, and the oxidation, restriction that can suppress metallic aluminium more effectively the growing up of aluminum particulate during sintering, thereby be guided out design of the present invention.
Summary of the invention
The object of the present invention is to provide a kind of Al/Al of aluminium oxide coated metal aluminium
2O
3The preparation method of ceramic-metal composite is to improve Al/Al
2O
3The uniformity that two-phase distributes in the composite reduces the oxidation of metal A l phase simultaneously, and metal phase Al is coated on ceramic phase Al
2O
3In after introduce again.The preparation of the composite granule of aluminium oxide parcel aluminium mainly is to finish in liquid phase.This method is simple, is fit to large-scale production.
The present invention implements like this: with Al/Al
2O
3Nuclear-shell compound particle is second phase, with the Al of commercial large-scale production
2O
3Powder is a matrix, suitably adds sintering aid, prepares Al/Al by hot pressed sintering
2O
3Ceramic-metal composite.
Al/Al provided by the invention
2O
3The composite material preparation process process as shown in Figure 1, is characterized in that:
(1) aluminium powder with industrial mass production is the parcel that initiation material carries out powder, with the surface of the excessive aluminium powder of acid treatment, makes precipitating reagent with ammoniacal liquor, forms Al/AlOOHH in liquid phase earlier
2O nuclear-shell compound particle is again through suction filtration, washing, drying.The purpose of handling with diluted acid one is to form Al in solution
3+Thereby, for next wrapping up AlOOHH
2O provides the aluminium source; The 2nd, along with emitting of hydrogen in reaction, the aluminium powder surface can form defectives such as many pits, thereby the forming core point of heterogeneous forming core is provided for ensuing parcel.
(2) used diluted acid H
+Concentration is 0.2-1.0M, with the reaction temperature of excessive aluminium powder be 20-80 ℃, the aluminium that participates in reaction accounts for the 30-50% of initial aluminium powder volume, the concentration of used ammoniacal liquor is 0.1-1.0M, Al in ammoniacal liquor and the solution
3+Mol ratio Al
3+: NH
3H
2O is 1: 3, and magnetic agitation is followed in reaction, generates to contain Al/AlOOHH
2The sediment of O nuclear-shell compound particle.Spend deionised water 3-4 time, ethanol washing 1-2 time, the drying precipitate condition is 80-100 ℃, is incubated 2-8 hour.
(3) with prepared Al/AlOOHH
2O nuclear-shell compound particle (mass content of aluminium is 1-15%) by a certain percentage is mixed with commercially available alumina powder jointed ball milling.Ball-milling medium is an absolute ethyl alcohol, and magnesium salts is dissolved in the absolute ethyl alcohol by a certain percentage adds as sintering aid with the solution form, and magnesian mass content is that 0.3-0.7% is (with Al/Al
2O
3Be benchmark, add).
(4) powder behind the batch mixing was calcined 1-2 hour down at 400-600 ℃ after super-dry.At this moment, the powder behind Al (4) batch mixing was calcined 1-2 hour down at 400-600 ℃ after super-dry.At this moment, the shell AlOOHH of Al
2O is transformed into unbodied Al
2O
3, form Al/Al
2O
3Nuclear-shell compound particle.Magnesium salts is decomposed into magnesia.Baking temperature is 80-100 ℃, and the time is 5-10 hour.
(5) hot pressed sintering prepares Al/Al
2O
3Ceramic-metal composite, sintering temperature are 1350~1450 ℃, and temperature retention time is 10~30 minutes, and pressure is 20~30MPa, and the selection inert gas is a protective atmosphere.
Al/Al provided by the invention
2O
3Ceramic-metal composite preparation method's characteristics are:
(1) production technology is simple.
(2) raw material is cheap and easy to get, and equipment needed thereby is simple, is easy to realize suitability for industrialized production.
(3) compare with matrix material, the mechanical property of material is significantly improved.
(4) this composite has crucial practical value and wide application prospect in fields such as Aero-Space, electronics industry, automobile, mechanical wearing piece, structural member and chemical industry corrosion barrier.
Description of drawings
Fig. 1 Al/Al provided by the invention
2O
3Preparation technology's flow chart of ceramic-metal composite
The X-ray diffraction spectrogram (XRD) of Fig. 2 different process stage powder and block
(a) commercially available Al
2O
3
(b) prepared Al/AlOOHH
2O and commercially available Al
2O
3Powder after ball milling is mixed
(c) the ball milling powder was calcined through 500 ℃ in 1 hour
(d) through 1400 ℃, 30 minutes, 30MPa, Ar atmosphere hot pressing sintering
The ESEM (SEM) of Fig. 3 different phase gained sample and transmission electron microscope (TEM) pattern photo
(a) as the Al/AlOOHH that adds phase
2O nuclear-shell compound particle
(b) the mixed back of commercial alumina and coated powder gained powder
(c) 1350 ℃, 30MPa, Ar atmosphere, the fracture apperance of insulation 30min hot pressed sintering gained sample
(d) 1450 ℃, 30MPa, Ar atmosphere, the fracture apperance of insulation 30min hot pressed sintering gained sample
Fig. 4 is according to the prepared Al/Al of embodiment 2
2O
3Ceramic-metallic fracture photo
The specific embodiment
Further specify embodiment and effect with following non-limiting embodiment:
Preparation 0.1M dilution heat of sulfuric acid and 0.6M ammonia spirit, the 15g particle diameter is distributed as 1~4 μ m aluminium powder to add violent magnetic force and adds (Al that participate in acid reaction this moment accounts for 30%) in the 2500mL dilution heat of sulfuric acid of thermal agitation, reaction temperature is 60 ℃, can observe micro-bubble and has overflowed from solution.After treating that acid exhausts, stop heating, and dropwise add the ammonia spirit of 833mL 0.6M.With sediment spend deionised water three times, absolute ethanol washing twice, suction filtration.Products therefrom is put into baking oven 100 ℃ of dryings 8 hours.Ball mill mixing is according to Al, Al
2O
3Be respectively 5%, 95% and 0.3% with the mass content of MgO and carry out, take by weighing 5.92g composite granule, 43.12g Al respectively
2O
3Mg (NO with 0.96g
3)
26H
2O, and earlier magnesium nitrate is dissolved in ball-milling medium-absolute ethyl alcohol, add composite granule and AlO again
3With the powder behind the ball milling 500 ℃ of calcinings after 1 hour in 1400 ℃, 30MPa insulation 30 minutes, Ar atmosphere is carried out hot pressed sintering.Fig. 2 is the X-ray diffraction spectrogram of present embodiment different phase powder.As can be seen: used commercially available Al
2O
3Be with γ-Al
2O
3Be main transition state Al
2O
3(a); Behind the composite granule ball mill mixing, increased the diffraction maximum of metal A l in the collection of illustrative plates, owing to AlOOHH this moment
2O is an amorphous state, does not therefore have AlOOHH
2The characteristic peak of O (b); The ball milling powder was calcined, at this moment AlOOHH through 450 ℃ in 1 hour
2The O dehydration is decomposed into amorphous Al
2O
3, magnesium salts is decomposed into magnesia, because magnesian content is well below detectability, so does not occur its diffraction maximum (c) in the collection of illustrative plates; Through 1400 ℃, 30MPa is incubated 30 minutes, the Ar atmosphere hot pressing sintering, and this moment, diffracting spectrum was by α-Al
2O
3Form with the characteristic peak of Al, wherein the mass content of Al (5%) is near the detectability of XRD, and local amplification can be seen exist (d) of its characteristic peak.
Carry out morphology analysis from Fig. 3 ESEM and transmission electron microscope photo again: (a) Al/AlOOHH
2O nuclear-shell compound particle, the surface of aluminium is by tiny AlOOHnH as can be seen
2O coats, and has formed the compound particle with nucleocapsid structure; (b) behind the ball milling, still can clearly observe the clad on Al surface, nano level small-particle is used commercially available Al
2O
3Powder; (c) 1350 ℃, 30MPa, Ar atmosphere, the fracture apperance of insulation 30min hot pressed sintering gained sample: dense at the sample of 1350 ℃ of sintering as can be seen, crystallite dimension is more even, and average-size is about 700nm, and fracture mode is fractured into the master with the edge crystalline substance.Through test, this moment, the density of sample reached 96.7%, and bending strength is 486MPa, and fracture toughness is 3.8MPam
1/2(d) 1450 ℃, 30MPa, Ar atmosphere, the fracture apperance of insulation 30min hot pressed sintering gained sample: this moment, apparent in view growing up took place in crystal grain, and average grain diameter is about 1 μ m, and fracture mode still is to be fractured into the master along crystalline substance.Through test, this moment, the density of sample reached 98.1%, and bending strength is brought up to 534MPa, and fracture toughness is 5.5MPam
1/2Constant when other condition, bending strength reached and is 604MPa to the maximum when sintering temperature was 1400 ℃.
Embodiment 2
Regulate the mass percent of two-phase in the composite during ball mill mixing, and the shared percentage of sintering aid, the aluminium oxide, composite granule and the magnesium nitrate that take by weighing different amounts are prepared burden.All the other conditions are with embodiment 1.Fig. 4 is 10% for the mass content of Al, and the mass content of MgO is 0.5%, in 1400 ℃, and 25MPa, Ar atmosphere, the fracture apperance of insulation 10min gained sample.
Claims (7)
1, the Al/Al of aluminium oxide coated metal aluminium
2O
3The preparation method of ceramic-metal composite is characterized in that with Al
2O
3The composite granule of parcel Al is second phase, with the Al of industrial mass production
2O
3For matrix, ball mill mixing and add sintering aid, finally obtain Al/Al by hot pressed sintering
2O
3Composite, concrete processing step is:
(a) aluminium powder with industrial mass production is an initiation material, with the surface that diluted acid is handled excessive aluminium powder, makes precipitating reagent with ammoniacal liquor, forms Al/AlOOHH in liquid phase earlier
2O nuclear-shell compound particle, sediment is through suction filtration, washing, drying;
(b) with prepared Al/AlOOHH
2O nuclear-shell composite granule is that 1-15% mixes with the alumina powder jointed of commodity production by the mass content of aluminium;
(c) by ball mill mixing, as ball-milling medium, and magnesia quality percentage composition is that the magnesium salts of 0.3-0.7% is as sintering aid with alcohol;
(d) powder behind the ball milling is dry down in 80~100 ℃;
(e) dried powder is calcined down in 400~600 ℃, made AlOOHH
2The dehydration of O shell is decomposed into unbodied Al
2O
3, form Al/Al
2O
3Nuclear-shell compound particle, magnesium salts is decomposed into MgO simultaneously;
(f) powder after will calcining carries out hot pressed sintering, and sintering temperature is 1350~1450 ℃, and pressure is 20~30Mpa, and sintering atmosphere is inert gas shielding.
2, by the described preparation of claim 1 Al/Al
2O
3The method of ceramic-metal composite is characterized in that used and the diluted acid H that handles excessive aluminium powder in the step (a)
+Concentration is 0.2-1.0M, and treatment temperature is 20-80 ℃; The aluminium powder that participates in reaction accounts for the 30-50% of initial aluminium powder volume.
3, by the described preparation of claim 1 Al/Al
2O
3The method of ceramic-metal composite is characterized in that ammonia concn used in the step (a) is 0.1-1.0M, and Al
3+: NH
3H
2O is 1: 3.Reaction follows magnetic agitation to generate Al/AlOOHH
2The sediment of the nuclear of O-shell compound particle.
4, by claim 1 or 3 described preparation Al/Al
2O
3The method of ceramic-metal composite is characterized in that sediment spends deionised water 3-4 time, after ethanol washs 1-2 time, is 2-8 hour in 80-100 ℃ of dry down time.
5, by the described preparation of claim 1 Al/Al
2O
3The method of ceramic-metal composite is characterized in that the powder drying time is 5-10 hour behind step (d) ball milling.
6, by the described preparation of claim 1 Al/Al
2O
3The method of ceramic-metal composite is characterized in that 400-600 ℃ of calcination time is 1-2 hour in the step (e).
7, by the described preparation of claim 1 Al/Al
2O
3The method of ceramic-metal composite, temperature retention time is 10-30 minute when it is characterized in that in the step (f) sintering.
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CN103194632A (en) * | 2013-05-02 | 2013-07-10 | 西安卓曦新材料科技有限公司 | Preparation method of high-volume fraction micrometer alumina ceramic enhanced composite material |
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CN107814560A (en) * | 2017-09-30 | 2018-03-20 | 江苏金石研磨有限公司 | A kind of ceramic grinding ball rolls shaping composite fortifier and preparation method thereof and its application method |
CN109807692A (en) * | 2017-11-21 | 2019-05-28 | 中芯国际集成电路制造(上海)有限公司 | A kind of lapping liquid, the method and chemical and mechanical grinding method for preparing lapping liquid |
CN114959410A (en) * | 2022-06-10 | 2022-08-30 | 季华实验室 | Nano-alumina-reinforced aluminum-based boron carbide, preparation method thereof and neutron absorbing material |
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