CN101580343B - Rare earth-mixing high strength lithium bisilicate sitall material and preparation method thereof - Google Patents
Rare earth-mixing high strength lithium bisilicate sitall material and preparation method thereof Download PDFInfo
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- CN101580343B CN101580343B CN2009100437116A CN200910043711A CN101580343B CN 101580343 B CN101580343 B CN 101580343B CN 2009100437116 A CN2009100437116 A CN 2009100437116A CN 200910043711 A CN200910043711 A CN 200910043711A CN 101580343 B CN101580343 B CN 101580343B
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Abstract
The present invention relates to a rare earth-mixing high strength lithium bisilicate sitall material and a preparation method thereof. Parent glass of the invention includes the following components according to molar percentage: 61.2 to 66.0 percent of SiO2, 0 to 2.5 percent of B2O3, 0 to 1.6 percent of Al2O3, 1.0 to 3.7 percent of P2O5, 0 to 2.3 percent of ZrO2, 1.0 to 1.8 percent of K2O, 24.2 to 31.8percent of Li2O, 0 to 2.0 percent of MgO, 0 to 2.0 percent of CaO, and 0.5 to 4.2 percent of La2O3+Y2O3. A corresponding raw material prepared from the oxidates is processed by the steps of ball milling, 80 mesh sieve sieving and uniform mixing to obtain a batch; the batch is led into a copple to be melted after the temperature from 1480 to 1520 DEG C is maintained for 2 to 3 hours, and the melted batch is cast into a stainless steel mould to be molded and then is annealed at 500 DEG C for 0.5 hour; and the step of coring is carried out in a resistance furnace at the temperature from 500 to 550 DEG C for 1 hour, and the step of crystallization is carried out at the temperature from 600 to 850 DEG C for 2 hours. The crystallization degree of the sitall is as high as 60 to 70 percent, the flexural strength is 100 MPa or more higher than the sitall to which the rare earth oxides are not added, the highest flexural strength reaches 334 MPa, the maximum elastic modulus reaches 143 GPa, and the highest fracture toughness reaches 3.34 MPa-m<1/2>. The sitall of the invention has favorable stability, and the heat treatment temperature is lower and is easy to control.
Description
Technical field
The present invention relates to microcrystal glass material and preparation method thereof, particularly rear-earth-doped high-intensity two lithium silicate devitrified glasses and preparation method thereof.
Background technology
Devitrified glass has obtained in fields such as biomedicine, machinery, electronics, Aerospace Engineering to use widely since succeeding in developing.In the past few decades, the researchist has carried out a large amount of exploratory developments to the technology of preparing and the composition-structure-performance relation of the coring of the composition designing technique of parent glass, devitrified glass and crystallization mechanism, devitrified glass.Compare with traditional glass, devitrified glass has the performance of good calorifics, mechanics, electricity aspect, for example low thermal coefficient of expansion, high compressive strength, high-flexural strength, high elastic coefficient, high-fracture toughness etc.Yet the bending strength of most of devitrified glasses is in 200MPa, and Young's modulus is in 100GPa, and fracture toughness property is less than 2.0MPa.m
1/2
The researchist has carried out big quantity research to the mechanical property that how to improve devitrified glass both at home and abroad, and the devitrified glass of separating out two lithium silicate principal crystalline phases is one of research emphasis, and this material is mainly used in dental prosthetic.U.S. Pat 6802894B2 discloses a kind of technology of preparing and material property of two lithium silicate devitrified glasses.Its compositing characteristic of giving an example is SiO
2More than the content 65wt%, bending strength is up to 480-500MPa, but does not relate to Young's modulus and two main Mechanical indexs of fracture toughness property in the patent.Subsequently, U.S. Pat 7452836B2 also discloses the technology of preparing and the material property of another kind of two lithium silicate devitrified glasses.Its compositing characteristic is SiO
2Content 64%-73wt% introduces P at least
2O
5Or a kind of in the compound of Pt, Ag, Cu, W as nucleator, maximum bending strength reaches 786MPa (twin shaft flexural strength, example 9), and this patent does not relate to Young's modulus and two mechanical performance index of fracture toughness property yet.Chinese patent ZL200510010431.7 has reported with Li
2O-SiO
2-P
2O
5Devitrified glass and system method thereof for main raw material.Its compositing characteristic is that parent glass contains P
2O
5, SiO
2, ZnO, CaO, K
2O, Li
2Six kinds of compositions of O, its preparation technology's characteristics are that the glass that high temperature melting makes forms the devitrified glass that contains two lithium silicate principal crystalline phases through shrend, grinding, hot pressed sintering.The maximum bending strength of this devitrified glass is 249.9MPa, fracture toughness property 2.2MPa.m
1/2Chinese patent application 200710072597.0 has been reported with ZrO
2Two lithium silicate glass ceramic composites and system method thereof for toughener.Its compositing characteristic is to introduce 5～30% (wt%) ZrO in two silicic acid acid lithium devitrified glass
2Its preparation technology's characteristics are, the glass shrend that high temperature melting is made, grind to form glass powder, then with itself and ZrO
2Mixing is also ground, and makes composite granule, makes through vacuum heating-press sintering to contain ZrO
2The two silicic acid acid lithium glass ceramic composite of wild phase.The maximum bending strength of this devitrified glass is at 330MPa, fracture toughness property 3.54MPam
1/2Although the microcrystal glass material of Huo Deing has high intensity and fracture toughness property in this way, complicated process of preparation, appointed condition require height, are difficult to obtain translucent material.
Summary of the invention
The purpose of this invention is to provide two lithium silicate devitrified glasses of a kind of excellent property and preparation method thereof, the present invention is at SiO
2, B
2O
3, P
2O
5, ZrO
2, K
2O, Li
2Parent glass such as O, MgO, CaO mix a certain amount of rare earth oxide in forming, and prescription and thermal treatment process have been done a large amount of research, through comparing repeatedly and screening, make two lithium silicate devitrified glasses.Concrete technical scheme of the present invention is as follows:
The devitrified glass that the present invention relates to, its parent glass is by SiO
2, B
2O
3, P
2O
5, ZrO
2, K
2O, Li
2O, MgO, CaO, La
2O
3, Y
2O
3Form Deng oxide compound.The molar percentage compositing range of each oxide compound is respectively: SiO
2: 61.2～66.0%, B
2O
3: 0～2.5%, Al
2O
3: 0～1.6%, P
2O
5: 1.0～3.7%, ZrO
2: 0～2.3%, K
2O:1.0～1.8%, Li
2O:24.2～31.8%, MgO:0～2.0%, CaO:0～2.0%, La
2O
3+ Y
2O
3: 0.5～4.2%.
The preparation process of the rare earth-mixing high strength lithium bisilicate sitall that the present invention relates to is as follows:
1) founding of glass: chemical constitution according to claim 1 is converted into the weight of corresponding raw material with it.Accurately take by weighing the weight of respectively forming corresponding raw material, and through ball milling, cross 80 mesh sieves, mix and make admixtion.
2) admixtion is put into quartz crucible or corundum crucible, the temperature rise rate with 5 ℃/min～10 ℃/min in the Si-Mo rod resistance furnace is warming up to 1480～1520 ℃, and insulation 2～3h makes uniform glass solution.
3) the glass solution is poured into rapidly in the stainless steel mould of preheating, and moved to rapidly in the resistance furnace that has been heated to preheating temperature, the 0.5h that anneals under 500 ℃ of temperature obtains colourless, transparent, even, bubble-free mass foundation glass.
4) according to the DSC curve of parent glass, parent glass is heat-treated in resistance furnace, i.e. coring 1h under 500 ℃～550 ℃ temperature, crystallization 2h under 600 ℃～850 ℃ temperature, after heat treatment furnace cooling is to room temperature for sample, and making with two lithium silicates is the high strength micro-crystalline glass of principal crystalline phase.
The devitrified glass of the present invention's preparation has good mechanical property, high-flexural strength, high elastic coefficient, and high-fracture toughness, chemical stability, and have translucency; The preparation method of this devitrified glass is simple, and is environmentally friendly, do not introduce heavy metal ion, and production cost is lower.
Embodiment
The invention will be further described below in conjunction with embodiment, but should not limit protection scope of the present invention with this.
Embodiment 1: the devitrified glass that the present invention relates to, its parent glass is by B
2O
3, SiO
2, P
2O
5, K
2O, Li
2O, ZrO
2, La
2O
3Form, each content of forming is B
2O
3: 2.3mol%, SiO
2: 65.0mol%, P
2O
5: 1.2mol%, K
2O:1.8mol%, Li
2O:27.1mol%, ZrO
2: 1.8mol%, La
2O
3: 0.8mol%.
Embodiment 2: the devitrified glass that the present invention relates to, its parent glass is by B
2O
3, SiO
2, P
2O
5, K
2O, Li
2O, Al
2O
3, ZrO
2, Y
2O
3Form, each content of forming is B
2O
3: 2.1mol%, SiO
2: 64.2mol%, P
2O
5: 1.0mol%, K
2O:1.6mol%, Li
2O:26.8mol%, Al
2O
3: 1.4mol%, ZrO
2: 1.7mol%, Y
2O
3: 1.3mol%.
Embodiment 3: the devitrified glass that the present invention relates to, its parent glass is by B
2O
3, SiO
2, P
2O
5, K
2O, Li
2O, Al
2O
3, ZrO
2, Y
2O
3, La
2O
3Form the B that each is formed
2O
3: 1.1mol%, SiO
2: 61.6mol%, P
2O
5: 2.5mol%, K
2O:1.2mol%, Li
2O:30.8mol%, Al
2O
3: 1.5mol%, ZrO
2: 1.3mol%, Y
2O
3: 1.5mol%, La
2O
3: 1.0mol% forms.
Embodiment 4: the devitrified glass that the present invention relates to, its parent glass is by MgO, SiO
2, P
2O
5, K
2O, Li
2O, Al
2O
3, ZrO
2, Y
2O
3, La
2O
3Form MgO:2.0mol%, SiO that each is formed
2: 62.0mol%, P
2O
5: 2.5mol%, K
2O:1.2mol%, Li
2O:30.8mol%, Al
2O
3: 1.5mol%, Y
2O
3: 1.2mol%, La
2O
3: 0.8mol% forms.
Embodiment 5: the devitrified glass that the present invention relates to, its parent glass is by CaO, SiO
2, P
2O
5, K
2O, Li
2O, Al
2O
3, ZrO
2, Y
2O
3, La
2O
3Form CaO:2.0mol%, SiO that each is formed
2: 62.0mol%, P
2O
5: 2.5mol%, K
2O:1.2mol%, Li
2O:30.8mol%, Al
2O
3: 1.5mol%, Y
2O
3: 1.2mol%, La
2O
3: 0.8mol% forms.
Embodiment 1,2,3,4 is different with the chemical constitution of 5 glass, but the melting technology of glass is close, and the detailed process from glass to the devitrified glass is:
1), the founding of glass: according to the chemical constitution of embodiment 1,2,3,4 and 5 glass, accurately take by weighing and respectively form corresponding raw material, weighing and with the dusty raw materials ball milling, is crossed 80 mesh sieves at mixing;
2), mixed powder is put into quartz crucible or corundum crucible, in the Si-Mo rod resistance furnace,, be warming up to certain temperature of fusion and be incubated certain hour, make the starting powder fusing obtain uniform glass solution with the temperature rise rate of 5 ℃/min～10 ℃/min; In the specific implementation process,, be molten into 1480 ℃, insulation 2.5h for embodiment 1; For embodiment 2, be molten into 1500 ℃, insulation 2h; For embodiment 3, be molten into 1500 ℃, insulation 3h; For embodiment 4 and 5, be molten into 1520 ℃, insulation 2.5h;
3), the glass solution that obtains is poured into rapidly in the stainless steel mould of preheating, move to rapidly in the resistance furnace that has been heated to preheating temperature,, obtain colourless, transparent, even, bubble-free block glass at 500 ℃ of annealing 0.5h;
4), the parent glass that obtains is processed into needed shape;
5), the preparation method of devitrified glass: according to the DSC curve of parent glass, the glass sample that makes is heated to above 30 ℃ of left and right sides of glass transformation temperature nucleation 1h with the speed of 5 ℃/min, speed with 2 ℃/min is heated to crystallization peak temperature point crystallization 2h again, furnace cooling obtains having the rare earth-mixing high strength lithium bisilicate sitall material of translucency after room temperature.In the specific implementation process, for embodiment 1, its nucleation temperature is 520 ℃, and crystallization temperature is 785 ℃; For embodiment 2, its nucleation temperature is 515 ℃, and crystallization temperature is 800 ℃; For embodiment 3, its nucleation temperature is 525 ℃, and crystallization temperature is 770 ℃; For embodiment 4 and 5, its nucleation temperature is 500 ℃, and crystallization temperature is 750 ℃.
The principal crystalline phase of the high strength micro-crystalline glass of the present invention's preparation is two lithium silicates, this crystalline crystallization degree reaches as high as 60～70%, bending strength is than more than the high 100MPa of glass that does not add rare earth oxide, the bending strength of embodiment 3 is up to 334MPa, Young's modulus is 143GPa, and fracture toughness property is 3.34MPam
1/2The mechanical property of each embodiment devitrified glass sees Table in 1.
Table 1
The mechanical property table of table 1 specific embodiment 1～5
Claims (5)
1. rear-earth-doped high-intensity two lithium silicate devitrified glasses, it is characterized in that: parent glass is by SiO
2, B
2O
3, Al
2O
3, P
2O
5, ZrO
2, K
2O, Li
2O, MgO, CaO, La
2O
3And Y
2O
3Oxide compound is formed, and the molar percentage compositing range of each oxide compound is respectively SiO
2: 61.2～66.0%, B
2O
3: 0～2.5%, Al
2O
3: 0～1.6%, P
2O
5: 1.0～3.7%, ZrO
2: 0～2.3%, K
2O:1.0～1.8%, Li
2O:24.2～31.8%, MgO:0～2.0%, CaO:0～2.0%, La
2O
3+ Y
2O
3: 0.5～4.2%.
2. two lithium silicate devitrified glasses according to claim 1 is characterized in that: each content of forming is B
2O
3: 2.3mol%, SiO
2: 65.0mol%, P
2O
5: 1.2mol%, K
2O:1.8mol%, Li
2O:27.1mol%, ZrO
2: 1.8mol%, La
2O
3: 0.8mol%.
3. two lithium silicate devitrified glasses according to claim 1 is characterized in that: each content of forming is B
2O
3: 2.1mol%, SiO
2: 64.2mol%, P
2O
5: 1.0mol%, K
2O:1.6mol%, Li
2O:26.8mol%, Al
2O
3: 1.4mol%, ZrO
2: 1.7mol%, Y
2O
3: 1.3mol%.
4. two lithium silicate devitrified glasses according to claim 1 is characterized in that: each content of forming is CaO:2.0mol%, SiO
2: 62.0mol%, P
2O
5: 2.5mol%, K
2O:1.2mol%, Li
2O:30.8mol%, Al
2O
3: 1.5mol%, Y
2O
3: 1.2mol%, La
2O
3: 0.8mol%.
5. the preparation method of two lithium silicate devitrified glasses according to claim 1 is characterized in that comprising the following steps:
1) founding of glass: chemical constitution according to claim 1, accurately take by weighing the weight of respectively forming corresponding raw material, and through ball milling, cross 80 mesh sieves, mix and make admixtion;
2) admixtion is put into quartz crucible or corundum crucible, the temperature rise rate with 5 ℃/minute～10 ℃/minute in the Si-Mo rod resistance furnace is warming up to 1480～1520 ℃, and insulation 2-3h makes uniform glass solution.
3) the glass solution is poured into rapidly in the stainless steel mould of preheating, and moved to rapidly in the resistance furnace that has been heated to preheating temperature, the 0.5h that anneals under 500 ℃ of temperature obtains colourless, transparent, even, bubble-free mass foundation glass.
4) according to the DSC curve of parent glass, parent glass is heat-treated i.e. coring 1h under 500 ℃～550 ℃ temperature, crystallization 2h under 600 ℃～850 ℃ temperature in resistance furnace, after heat treatment furnace cooling is to room temperature, and making with two lithium silicates is the high strength micro-crystalline glass of principal crystalline phase.
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|---|---|---|---|
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|---|---|---|---|
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| CN103360041B (en) * | 2013-07-22 | 2014-07-02 | 哈尔滨工业大学（威海） | Carbon/lithium disilicate composite ceramic material and preparation method thereof |
| CN103553339B (en) * | 2013-09-30 | 2015-08-05 | 西安交通大学 | Lithium bisilicate microcrystal glass material prepared by hybrid reaction sintering process and method thereof |
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| CN106365456B (en) * | 2016-08-31 | 2019-06-25 | 东北大学秦皇岛分校 | Lithium bisilicate devitrified glass, preparation method and the application for dental material |
| CN107555801B (en) * | 2017-08-24 | 2020-10-16 | 陕西科技大学 | Method for preparing lithium disilicate glass ceramics |
| CN108409143A (en) * | 2018-06-13 | 2018-08-17 | 合肥协耀玻璃制品有限公司 | A kind of warping resistance devitrified glass |
| CN110423008B (en) * | 2019-08-27 | 2021-11-30 | 江西理工大学 | Microcrystalline solid electrolyte and preparation method thereof |
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| CN112939469B (en) * | 2021-03-23 | 2022-03-08 | 成都光明光电股份有限公司 | Glass ceramics and glass ceramics product |
| CN114538780B (en) * | 2022-01-27 | 2023-11-24 | 周口市中心医院 | Front tooth facing ceramic material and preparation method thereof |
| CN114956582A (en) * | 2022-07-07 | 2022-08-30 | 西安信征电子材料有限责任公司 | Application and production method of lithium silicate glass material vitrified glass powder |
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|---|---|---|---|---|
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| US7452836B2 (en) * | 2005-02-08 | 2008-11-18 | Ivoclar Vivadent Ag | Lithium silicate glass ceramic |
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2009
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| US6802894B2 (en) * | 1998-12-11 | 2004-10-12 | Jeneric/Pentron Incorporated | Lithium disilicate glass-ceramics |
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