Aluminosilicate glass compositions and strengthening process thereof

Abstract

The present application relates to the field of glass, in particular to an aluminosilicate glass composition and a strengthening process thereof, the aluminosilicate glass composition comprising: SiO2, Al2O3, Na2O, K2O, Li2O, MgO, BaO, P2O5, B2O3, Y2O3, Sc2O3 and La2O3. The aluminosilicate glass composition of the present application optimizes the glass network structure by precisely controlling the proportion of each component, and improves its stability, hardness and wear resistance. At the same time, the introduction of rare metal oxides such as Y2O3, Sc2O3 and La2O3 can fill the glass network gap during glass strengthening, enhance the density, reduce the glass surface defects, effectively inhibit the crack propagation, significantly improve the impact strength and toughness of the glass, and also can greatly increase the depth of compressive stress layer and surface compressive stress, further improve the comprehensive performance of the glass.

Description

Technical Field

[0001] This invention relates to the field of glass, and more specifically to an aluminosilicate glass composition and its strengthening process. Background Technology

[0002] In recent years, smartphones, tablets, and other devices have become increasingly popular, exhibiting a trend towards thinner and lighter designs. One problem arising from this trend is that the strength of the glass decreases as the thickness reduces. To meet usage requirements, the glass used in displays must maintain high strength even with a small thickness. To achieve this, the glass needs to be strengthened.

[0003] Chinese invention patent application number 201610277766.3 discloses an aluminosilicate glass, which, expressed as a mass percentage based on the following oxides, comprises the following components: 56.0%–68.0% silicon dioxide, 10.0%–22.0% aluminum oxide, 9.0%–15.0% sodium oxide, 2.0%–8.0% magnesium oxide, 0%–9.0% potassium oxide, and 0%–1.5% zirconium dioxide; wherein the total mass percentage of silicon dioxide and aluminum oxide is greater than or equal to 70% and less than or equal to 85%, and the total mass percentage of sodium oxide and potassium oxide is greater than or equal to 9% and less than or equal to 23%. This patent, by controlling the composition and proportion of aluminosilicate, produces a silicate glass with a neutral chromaticity, good light transmittance, and low haze. However, the glass has a large network gap, low density, many microscopic defects, insufficient toughness, and is prone to edge cracking, affecting user use and experience. Summary of the Invention

[0004] In order to overcome the shortcomings and deficiencies of the prior art, the present invention aims to provide an aluminosilicate glass composition and its strengthening process.

[0005] The objective of this invention is achieved through the following technical solution: an aluminosilicate glass composition comprising the following components in the indicated mass percentages: SiO2: 55.3%-64.8%, Al2O3: 12.4%-19.7%, Na2O: 2.1%-4.4%, K2O: 3.2%-8.6%, Li2O: 1.9%-6.5%, MgO: 1.5%-5%, BaO: 1.5%-4.2%, P2O5: 0.8%-4.5%, B2O3: 0.5%-2.5%, Y2O3: 0.1%-1.5%, Sc2O3: 0.1%-1%, and La2O3: 0.05%-0.8%; wherein the mass relationship between Y2O3, Sc2O3, and La2O3 satisfies: 0.8 ≤ Y2O3 + Sc2O3 + La2O3 ≤ 3.2.

[0006] The aluminosilicate glass composition of the present invention optimizes the glass network structure by precisely controlling the proportions of each component, thereby improving its stability, hardness, and wear resistance. Simultaneously, the introduction of rare metal oxides such as Y₂O₃, Sc₂O₃, and La₂O₃ fills the gaps in the glass network during glass strengthening, enhancing density, reducing surface defects, effectively inhibiting crack propagation, significantly improving the glass's impact strength and toughness, and also substantially increasing the depth of the compressive stress layer and surface compressive stress, further enhancing the overall performance of the glass.

[0007] Preferably, the aluminosilicate glass composition comprises the following components in mass percentage: SiO2: 57%-63%, Al2O3: 14%-18%, Na2O: 3%-3.8%, K2O: 3.8%-7.2%, Li2O: 2.3%-5.5%, MgO: 2%-4%, BaO: 1.8%-3.8%, P2O5: 1.1%-3.7%, B2O3: 0.7%-2.3%, Y2O3: 0.2%-1.2%, Sc2O3: 0.2%-0.8%, and La2O3: 0.1%-0.5%; wherein the mass relationship between Y2O3, Sc2O3, and La2O3 satisfies: 1 ≤ Y2O3 + Sc2O3 + La2O3 ≤ 2.5.

[0008] The reasons for limiting the composition of the aluminosilicate glass composition to the above-mentioned range are explained as follows:

[0009] SiO2, as a glass network forger, constructs a three-dimensional framework through Si-O-Si covalent bonds, determining the glass's chemical stability, light transmittance, and mechanical strength. When the SiO2 content is below 53%, the glass network structure becomes loose, the proportion of non-bridging oxygen increases, leading to a decrease in glass hardness. When the SiO2 content is above 65%, the glass's melting temperature rises, its brittleness increases, and microcracks are more likely to appear during hot working. Therefore, the SiO2 content is limited to 55.3%-64.8%, with a preferred content of 57%-63%.

[0010] Al₂O₃, as a network intermediate, participates in the formation of the glass network structure and can enhance the stability of the network structure. 3+ Al2O3 can form [AlO4] tetrahedra to participate in network construction, thereby improving ion exchange rate and hardness. When the Al2O3 content is below 10%, the ion exchange efficiency decreases, the surface compressive stress layer depth is insufficient during glass strengthening, the bending resistance is poor, and the resulting glass product has poor stability and low mechanical strength. When the Al2O3 content is above 23%, the viscosity of the glass increases, making it difficult to form irregularly shaped glasses, and Al2O3 supersaturation easily induces crystallization. Therefore, the Al2O3 content is limited to 12.4%-19.7%, with a preferred content of 14%-18%.

[0011] Na₂O provides Na+ As the primary ion source for chemical strengthening, driving surface K + Displacement reaction. When the Na₂O content is below 1.5%, Na can be exchanged. + Insufficient concentration results in an inadequate surface compressive stress layer depth and low strengthening efficiency. When the Na2O content exceeds 6%, it weakens the glass network structure, reduces water resistance, and easily induces stress relaxation at high temperatures. The Al2O3 content is limited to 2.1%-4.4%, with a preferred content of 3%-3.8%.

[0012] K2O through K + Greater ion exchange with molten salt replenishes the strength of the surface compressive stress layer. When the K₂O content is below 2%, K + Insufficient K2O participation results in a gentle surface compressive stress gradient and weak scratch resistance. When the K2O content exceeds 9%, K... + Low mobility; excessive amounts can block ion channels and inhibit Na+. + / Li + Diffusion. Therefore, the K2O content is limited to 3.2%-8.6%, preferably 3.8%-7.2%.

[0013] Li in Li2O + The high mobility of Li₂O allows it to participate in deep ion exchange, increasing the depth of the compressive stress layer. When the Li₂O content is below 1.5%, the deep strengthening effect of the glass is weak, and the bending fatigue life is short. When the Li₂O content is above 7%, the supersaturated Li₂O… + This can cause glass phase separation (such as the precipitation of Li2SiO3), and at the same time, the acid resistance of the glass will decrease. Therefore, the content of Li2O is limited to 1.9%-6.5%, and preferably 2.3%-5.5%.

[0014] MgO can lower the melting point of glass, improve homogeneity, increase hydrolysis resistance, and enhance durability. When the MgO content is below 1%, its effect on improving glass homogeneity, hydrolysis resistance, and durability is limited; when the MgO content is above 6%, it will over-fill the glass network voids and inhibit Na+. + / Li + This allows for deep diffusion. Therefore, the MgO content is limited to 1.5%-5%, preferably 2%-4%.

[0015] BaO can reduce the coefficient of thermal expansion of glass. It combines with non-bridging oxygen in the SiO2 / Al2O3 network, covering voids of different sizes and thus homogenizing ion migration rates. When the BaO content is below 1%, its effect on filling large voids in the glass network is limited and it cannot reduce the coefficient of thermal expansion. When the BaO content is above 5%, excessive BaO... 2+ It will clog Na + / Li+ This creates migration channels and reduces the depth of the compressive stress layer. Therefore, the BaO content is limited to 1.5%-4.2%, preferably 1.8%-3.8%.

[0016] P2O5 can form [PO4] tetrahedra in glass, regulating the connectivity of the glass network, reducing high-temperature viscosity, and suppressing phase separation. When the P2O5 content is below 0.5%, the uniformity of the glass melt is poor, and the effect of reducing high-temperature viscosity is ineffective; when the P2O5 content is above 6%, the increase in POP chains leads to a decrease in chemical stability and corrosion resistance. Therefore, the P2O5 content is limited to 0.8%-4.5%, preferably 1.1%-3.7%.

[0017] B2O3 acts as an auxiliary glass network former, and its BO3 / BO4 structure can lower the melting temperature and improve processability. When the B2O3 content is below 0.5%, the melting temperature is high, making glass processing difficult; when the B2O3 content is above 3%, the tendency for BO bond hydrolysis increases, and water resistance deteriorates significantly. Therefore, to balance energy saving and water resistance, the B2O3 content is limited to 0.5%-2.5%, preferably 0.7%-2.3%.

[0018] Y₂O₃ has a high charge density, preferentially occupying the tetrahedral interstices in the glass network and forming strong bonds with [AlO₄] or [SiO₄] units, reducing the number of non-bridging oxygen atoms and making the network structure more compact. Simultaneously, Y₂O₃… 3 Y₂O₃ accumulates at the crack tip, inhibiting crack propagation through a pinning effect and improving fracture toughness. When the Y₂O₃ content is higher than 1.5%, Y₂O₃... 3 Supersaturation leads to glass phase separation, forming the precipitation of Y-Al-Si-O crystalline phases, and also reduces light transmittance. Therefore, the content of Y2O3 is limited to 0.1-1.5%, preferably 0.2%-1.2%.

[0019] Sc2O3 can ionize into Sc during strengthening. 3+ ,Sc 3+ It is the smallest high-charge cation among rare earth elements, capable of embedding into the tetrahedral interstices of a glass network to optimize local stress distribution; during the strengthening process, Sc 3+ With K in molten salt + A local electric field gradient is formed, accelerating Na + The directional migration of Sc enhances the strengthening effect, improving both fatigue resistance and corrosion resistance. When the Sc2O3 content is higher than 1.5%, Sc 3+ With Al 3+ Competitive coordination leads to a weakening of the Al2O3 network and a decrease in glass hardness. Therefore, the Sc2O3 content is limited to 0.1%-1%, preferably 0.2%-0.8%.

[0020] La2O3 can enhance the environmental resistance of glass, reduce its high-temperature viscosity, and improve the forming precision of irregularly shaped glass. When the La2O3 content is higher than 1%, La... 3+ Competition for charge compensation with alkali metal ions leads to a decrease in ion exchange rate, reducing the strengthening effect of the glass. Therefore, the content of La2O3 is limited to 0.05%-0.8%, preferably 0.1%-0.5%.

[0021] Y₂O₃, Sc₂O₃, and La₂O₃, as rare earth oxides, possess high field strength and small ionic radii, enabling them to embed into the interstitial sites of aluminosilicate glass networks, filling structural defects and significantly improving the density and mechanical strength of the glass. They also enhance resistance to water, acid, and alkali corrosion. When the ratio of Y₂O₃ + Sc₂O₃ + La₂O₃ ≤ 0.5, the interstitial sites in the glass network cannot be effectively filled, leading to decreased density, increased microscopic defects, and failure to achieve the desired enhancement of toughness and mechanical strength. When the ratio of Y₂O₃ + Sc₂O₃ + La₂O₃ ≥ 4, excessive rare earth oxides cause over-crosslinking of the glass network, resulting in increased glass brittleness, decreased impact resistance, and increased risk of crystallization. Therefore, the content of these three rare metal oxides is limited to 0.8 ≤ Y₂O₃ + Sc₂O₃ + La₂O₃ ≤ 3.2, with a preferred content of 1 ≤ Y₂O₃ + Sc₂O₃ + La₂O₃ ≤ 2.8.

[0022] Preferably, the mass relationship between MgO, BaO, and SiO2 satisfies: (MgO + BaO) / SiO2 = 1:7.9-15.7. MgO and BaO, as mixed alkaline earth metals, optimize ion migration suppression capabilities through the "mixed alkaline earth effect." 2+ Fill small gaps, Ba 2+ Occupying large voids and synergistically filling glass voids can improve the uniformity of ion diffusion. When (MgO+BaO) / SiO2 is greater than 1:7.9, excess alkaline earth metals cause glass embrittlement and also block Na+. + / K + The diffusion channels are affected, impacting the strengthening effect of the glass; when (MgO+BaO) / SiO2 is less than 1:15.7, it fails to fill the glass voids. Therefore, the (MgO+BaO) / SiO2 ratio is limited to between 1:7.9 and 15.7.

[0023] Preferably, the mass ratio of P2O5, B2O3, SiO2, and Al2O3 satisfies: (P2O5+B2O3) / (SiO2+Al2O3) = 1:12.1-18.7. B2O3 lowers the glass melting temperature, while P2O5 lowers high-temperature viscosity and improves melt uniformity; the two work synergistically to facilitate the processing of irregularly shaped glass. P2O5 introduces [PO4] tetrahedra, which, together with the BO3 / BO4 of B2O3, regulates network connectivity. When (P2O5+B2O3) / (SiO2+Al2O3) is greater than 1:11.5, the ion exchange rate decreases, weakening the strengthening effect; when (P2O5+B2O3) / (SiO2+Al2O3) is less than 1:19, the effects of lowering the glass melting temperature, reducing high-temperature viscosity, and improving melt uniformity are not achieved.

[0024] Another objective of this invention is achieved through the following technical solution: a strengthening process for aluminosilicate glass, comprising the following steps:

[0025] (1) First strengthening: Heat the aluminosilicate glass to 620-680℃ and then perform rapid cooling treatment;

[0026] (2) Second strengthening: Heat the glass that has been strengthened once to 300-350℃ and preheat for 1-2 hours. Then put the preheated glass into the first molten salt and strengthen it at 385-405℃ for 3-4 hours.

[0027] (3) Third strengthening: The glass that has been strengthened twice is placed in the second molten salt and strengthened at 420-430℃ for 8-10 hours to obtain aluminosilicate glass.

[0028] The first strengthening process, involving high-temperature heating and cooling, improves the internal stress distribution of the glass, laying the foundation for subsequent strengthening. The second and third strengthening processes, through ion exchange in different molten salts, further optimize the stress distribution on the glass surface and inside, improving the glass's impact and scratch resistance. This invention combines physical and chemical strengthening, employing three strengthening treatments to progressively improve the glass's hardness, toughness, and fatigue resistance. Compared to existing chemical strengthening processes, this method can increase the strength of aluminosilicate glass by more than 10%.

[0029] Preferably, in step (1), the rapid cooling process has a cooling rate of 120-180℃ / s, cooling to below 250℃. After the glass surface is rapidly solidified by the cold treatment, the interior slowly shrinks, and the tensile stress and surface compressive stress together form a "sandwich" structure, significantly enhancing the glass's bending strength and impact resistance.

[0030] Preferably, in step (1), the cooled aluminosilicate glass undergoes surface polishing treatment to a depth of 4-10 μm. Polishing the surface of the aluminosilicate glass that has undergone physical strengthening before chemical strengthening can eliminate surface defects caused by physical strengthening, remove the surface damage layer, reduce surface roughness, and ensure the uniformity of subsequent ion exchange.

[0031] Preferably, in step (2), the first molten salt comprises the following raw materials by mass percentage: KNO2: 64%-76%, NaNO3: 21%-31%, and nano-silica dispersion: 3%-5%. Adding nano-silica dispersion to the first molten salt can improve its fluidity and increase the KNO2 content. + / Na + The exchange rate.

[0032] Preferably, in step (3), the second molten salt comprises the following raw materials by weight percentage: KNO3: 70%-78%, NaNO3: 16%-24%, and nano-silica dispersion: 3-7%. Adding nano-silica dispersion to the second molten salt can improve the fluidity of the first molten salt and increase the KNO3 content. + / Na + The exchange rate.

[0033] Preferably, the nano-silica has a particle size of 10-50 nm and its surface is modified with a silane coupling agent. The "ball effect" of the modified nano-SiO2 reduces the dynamic viscosity of the molten salt by 10%-15%, improving the fluidity of the molten salt and ensuring the uniformity of ion exchange in irregularly shaped glasses; simultaneously, the silane groups on the SiO2 surface form hydrogen bonds with the Si-O network in the glass, locally opening the glass structure and accelerating the Na+ exchange. + Dissolution and K + Penetration increases the exchange rate by 20-30%.

[0034] The beneficial effects of this invention are as follows: By precisely controlling the proportions of each component, the glass network structure of the aluminosilicate glass composition of this invention is optimized, thereby improving its stability, hardness, and wear resistance. Simultaneously, the introduction of rare metal oxides such as Y₂O₃, Sc₂O₃, and La₂O₃ can fill the gaps in the glass network during glass strengthening, enhancing density, reducing surface defects, effectively inhibiting crack propagation, significantly improving the impact strength and toughness of the glass, and also greatly increasing the depth of the compressive stress layer and surface compressive stress, further enhancing the overall performance of the glass.

[0035] The strengthening process of this invention combines physical strengthening with chemical strengthening, and employs three strengthening treatments to gradually improve the hardness, toughness and fatigue resistance of the glass. Compared with existing chemical strengthening processes, this strengthening process can increase the strength of the strengthened aluminosilicate glass by more than 10%. Detailed Implementation

[0036] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to embodiments. The content mentioned in the embodiments is not intended to limit the present invention.

[0037] Example 1

[0038] An aluminosilicate glass composition comprising the following components in weight percentages: SiO2: 57%, Al2O3: 18%, Na2O: 3.8%, K2O: 7.2%, Li2O: 2.3%, MgO: 2%, BaO: 1.8%, P2O5: 3.7%, B2O3: 2.3%, Y2O3: 1.2%, Sc2O3: 0.2%, and La2O3: 0.5%.

[0039] A strengthening process for aluminosilicate glass includes the following steps:

[0040] (1) First strengthening: Aluminosilicate is heated to 620°C to obtain heated glass, and then subjected to rapid cooling treatment;

[0041] (2) Second strengthening: The glass that has been strengthened once is heated to 300°C and preheated for 2 hours. The preheated glass is then placed in the first molten salt and strengthened at 385°C for 4 hours.

[0042] (3) Third strengthening: The glass that has been strengthened twice is placed in the second molten salt and strengthened at 420°C for 10 hours to obtain aluminosilicate glass.

[0043] In step (1), the cooling rate of the cooling process is 120℃ / s. After the aluminosilicate glass is cooled by step (1), the surface is polished to a depth of 4μm.

[0044] In step (2), the first molten salt comprises the following components by mass percentage: KNO3: 64%, NaNO3: 31%, and nano-silica dispersion: 5%.

[0045] In step (3), the second molten salt comprises the following components by mass percentage: KNO3: 70%, NaNO3: 24%, and nano-silica dispersion: 6%.

[0046] Example 2

[0047] An aluminosilicate glass composition comprising the following components in weight percentages: SiO2: 60%, Al2O3: 16%, Na2O: 3.4%, K2O: 6%, Li2O: 3.4%, MgO: 3%, BaO: 2.8%, P2O5: 2.4%, B2O3: 1.5%, Y2O3: 0.7%, Sc2O3: 0.5%, and La2O3: 0.3%.

[0048] A strengthening process for aluminosilicate glass includes the following steps:

[0049] (1) First strengthening: The aluminosilicate is heated to 650°C and then rapidly cooled.

[0050] (2) Second strengthening: The glass that has been strengthened once is heated to 325°C and preheated for 1.5 hours. The preheated glass is then placed in the first molten salt and strengthened at 395°C for 3.5 hours.

[0051] (3) Third strengthening: The glass that has been strengthened twice is placed in the second molten salt and strengthened at 425°C for 9 hours to obtain aluminosilicate glass.

[0052] In step (1), the cooling rate of the cooling process is 150℃ / s. After the aluminosilicate glass is cooled by step (1), the surface is polished to a depth of 7μm.

[0053] In step (2), the first molten salt comprises the following components by mass percentage: KNO3: 70%, NaNO3: 26%, and nano-silica dispersion: 4%.

[0054] In step (3), the second molten salt comprises the following components by mass percentage: KNO3: 74%, NaNO3: 21.5%, and nano-silica dispersion: 4.5%.

[0055] Example 3

[0056] An aluminosilicate glass composition comprising the following components in weight percentages: SiO2: 63%, Al2O3: 14%, Na2O: 3%, K2O: 3.8%, Li2O: 5.5%, MgO: 4%, BaO: 3.8%, P2O5: 1.1%, B2O3: 0.7%, Y2O3: 0.2%, Sc2O3: 0.8%, and La2O3: 0.1%.

[0057] A strengthening process for aluminosilicate glass includes the following steps:

[0058] (1) First strengthening: Aluminosilicate is heated to 680°C to obtain heated glass, and the heated glass is cooled.

[0059] (2) Second strengthening: The glass that has been strengthened once is heated to 350°C and preheated for 2 hours. The preheated glass is then placed in the first molten salt and strengthened at 405°C for 3 hours.

[0060] (3) Third strengthening: The glass that has been strengthened twice is placed in the second molten salt and strengthened at 430°C for 8 hours to obtain aluminosilicate glass.

[0061] In step (1), the cooling rate of the cooling process is 180℃ / s. After the aluminosilicate glass is cooled by step (1), the surface is polished to a depth of 10μm.

[0062] In step (2), the first molten salt comprises the following components by mass percentage: KNO3: 76%, NaNO3: 21%, and nano-silica dispersion: 3%.

[0063] In step (3), the second molten salt comprises the following components by mass percentage: KNO3: 78%, NaNO3: 19%, and nano-silica dispersion: 3%.

[0064] Comparative Examples 1-4

[0065] The aluminosilicate glass compositions of Comparative Examples 1-4 are shown in the table below, and the strengthening process is the same as that of Example 2.

[0066] Element / % Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 <![CDATA[SiO2]]> 59.4 62.4 58.1 61.4 <![CDATA[Al2O3]]> 15.2 14.9 15.3 17.1 <![CDATA[Na2O]]> 5.3 4.2 4.5 3.3 <![CDATA[K2O]]> 5.6 3.2 6.3 5.4 <![CDATA[Li2O]]> 4.5 3.9 4.3 2.4 MgO 1.9 2.3 3.2 2.9 BaO 3.1 1.9 2.4 2.2 <![CDATA[P2O5]]> 3.2 3.9 3.1 3.4 <![CDATA[B2O3]]> 1.8 2.1 2.3 1.4 <![CDATA[Y2O3]]> — 1.2 — — <![CDATA[Sc2O3]]> — — 0.5 — <![CDATA[La2O3]]> — — — 0.5

[0067] Comparative Example 5

[0068] The difference between Comparative Example 5 and Example 2 above is that step (1) first step strengthening is not performed.

[0069] Comparative Example 6

[0070] The difference between Comparative Example 6 and Example 2 above is that neither the first molten salt in step (2) nor the second molten salt in step (3) contains nano-silica dispersion.

[0071]

[0072] As can be seen from the table above, the aluminosilicate glasses prepared in Examples 1-3 of this invention improve their stability, hardness, and wear resistance by precisely controlling the proportions of each component and optimizing the glass network structure. Simultaneously, the introduction of rare metal oxides such as Y₂O₃, Sc₂O₃, and La₂O₃, compared to Comparative Examples 1-4, can fill the gaps in the glass network during glass strengthening, enhance density, reduce surface defects, effectively inhibit crack propagation, significantly improve the impact strength and toughness of the glass, and also greatly increase the depth of the compressive stress layer and surface compressive stress, further enhancing the overall performance of the glass.

[0073] The strengthening process in Examples 1-3 of this invention combines physical and chemical strengthening, employing a three-stage strengthening treatment to progressively improve the hardness, toughness, and fatigue resistance of the glass. Compared to Comparative Example 5, which only uses chemical strengthening, this strengthening process can increase the strength of the strengthened aluminosilicate glass composition by more than 10%. Furthermore, the introduction of an alkyl coupling agent-modified nano-silica dispersion into the first and second molten salts improves the fluidity of the molten salts and increases Kc compared to Example 6 without this dispersion. + / Na + The exchange rate is increased, thereby improving the mechanical properties of the aluminosilicate glass composition.

[0074] The above embodiments are preferred implementations of the present invention. In addition, the present invention can be implemented in other ways. Any obvious substitutions without departing from the concept of the present invention are within the protection scope of the present invention.

Claims

1. An aluminosilicate glass composition, characterized in that: The aluminosilicate glass composition comprises the following components in the indicated mass percentages: SiO2: 57%-63%, Al2O3: 14%-18%, Na2O: 3%-3.8%, K2O: 3.8%-7.2%, Li2O: 2.3%-5.5%, MgO: 2%-4%, BaO: 1.8%-3.8%, P2O5: 1.1%-3.7%, B2O3: 0.7%-2.3%, Y2O3: 0.2%-1.2%, Sc2O3: 0.2%-0.8%, and La2O3: 0.1%-0.5%; wherein the mass relationship between Y2O3, Sc2O3, and La2O3 satisfies: 1 ≤ Y2O3 + Sc2O3 + La2O3 ≤ 2.5; The strengthening process of the aluminosilicate glass includes the following steps: (1) First strengthening: Heat the aluminosilicate glass to 620-680℃ and then perform rapid cooling treatment; (2) Second strengthening: Heat the glass that has been strengthened once to 300-350℃ and preheat for 1-2 hours. Then put the preheated glass into the first molten salt and strengthen it at 385-405℃ for 3-4 hours. (3) Third strengthening: The glass that has been strengthened twice is placed in the second molten salt and strengthened at 420-430℃ for 8-10 hours to obtain aluminosilicate glass; In step (1), the rapid cooling process has a cooling rate of 120-180℃ / s, cooling down to below 250℃.

2. The aluminosilicate glass composition according to claim 1, characterized in that: The mass relationship between MgO, BaO and SiO2 satisfies: (MgO+BaO) / SiO2=1:7.9-15.

7.

3. The aluminosilicate glass composition according to claim 1, characterized in that: The mass relationship between P2O5, B2O3, SiO2 and Al2O3 satisfies: (P2O5+B2O3) / (SiO2+Al2O3)=1:12.1-18.

7.

4. The aluminosilicate glass composition according to claim 1, characterized in that: In step (1), the cooled aluminosilicate glass is subjected to surface polishing treatment with a polishing depth of 4-10μm.

5. The aluminosilicate glass composition according to claim 1, characterized in that: In step (2), the first molten salt comprises the following raw materials by mass percentage: KNO3: 64%-76%, NaNO3: 21%-31%, and nano silica dispersion: 3%-5%.

6. The aluminosilicate glass composition according to claim 1, characterized in that: In step (3), the second molten salt comprises the following raw materials by mass percentage: KNO3: 70%-78%, NaNO3: 16%-24%, and nano silica dispersion: 3-7%.

7. The aluminosilicate glass composition according to claim 5 or 6, characterized in that: The nano-silica has a particle size of 10-50 nm and its surface is modified with a silane coupling agent.

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