CN104062422B - Prediction method of transition temperature and hardness of glass - Google Patents

Abstract

The method for predicting the transition temperature and hardness of the glass of the present invention comprises the following steps: before step (1), a sample of the same type is tested for the coordination _C1 of the network former and the transition temperature _Tg1 of the glass, and then the following prediction steps are carried out ; ⑴ glass structure information detection; ⑵ structural coordination and network formation structural chain dimension calculation; ⑶ glass transition temperature and hardness prediction calculation formula; ⑷ glass transition temperature and hardness prediction calculation results. The application of the present invention proves that it can accurately predict the transition temperature and hardness of glass, especially for glass compositions with unknown properties; it can greatly reduce the number of damaged glass samples, improve the test efficiency of glass properties, reduce costs, and shorten testing Time; the operation is simple, and the performance of the glass can be corrected without a large number of thermodynamic and kinetic parameters required by the traditional method.

Description

Prediction method of transition temperature and hardness of glass

technical field

The invention belongs to the technical field of performance characterization testing of glass materials, and in particular relates to a method for predicting the transition temperature and hardness of glass.

Background technique

Glass has been widely used in various industrial fields because of its excellent light transmission, formability and mechanical properties. However, because glass is formed by rapid cooling of high-temperature melt, the detection of its thermal properties usually takes a lot of time and energy, and the detection method is relatively complicated. The transition temperature of glass is a very important thermal performance parameter, which plays an important guiding role in the relaxation of glass structure and the reduction of internal defects. The hardness of the glass bulk phase material at room temperature is an important criterion for determining its use value. However, because glass is a brittle material, its conventional testing method is to detect the hardness by a hardness tester. However, the hardness test also has strict requirements on the smoothness of the glass surface, which will take a lot of time for polishing the glass surface. Moreover, if the indenter pressure of the hardness tester is too high, it is easy to leave cracks on the glass surface, which will distort the data of the hardness test. At present, the transition temperature and hardness of glass cannot be tested non-destructively. Therefore, it is important to improve the detection efficiency of the transition temperature and hardness of the glass, minimize the damage to the sample during the detection, correctly evaluate the macroscopic performance of the glass from the microstructure, and form some support for the composition and design of the glass. At present, the industry is generally concerned.

At present, the commonly used methods for measuring the transition temperature and hardness of glass are the Vogel-Fulcher-Tammann method and the Avramov-Milchev method, both of which predict the transition temperature of glass through the viscosity corresponding to the temperature. However, they all have shortcomings. Among them, the Vogel-Fulcher-Tammann method will fail to predict when the glass is in a low-temperature dense state; and the Avramov-Milchev method will fail to predict when the glass is in an ultra-cold liquid state. At present, there is no predictive method that can effectively solve the problem of glass distortion in different states with temperature changes.

For the characterization methods of glass hardness, the existing methods are mainly direct test methods, such as "Knoops hardness method", "Vickers hardness method", etc., they all use the indentation area generated by the calculation unit as the withstand pressure As a result, the difference is only in the shape and size of the indenter. Obviously, this single test method is not suitable for testing the hardness of glass with different components in large quantities. The current research has found that through the glass microcoordination structure, the performance evaluation that changes continuously with the components can be realized, the large-scale prediction of the transition temperature and hardness of the glass can be realized, and the non-destructive testing and rapid prediction of the glass can be realized.

Contents of the invention

The object of the present invention is to solve above-mentioned deficiency, provide a kind of transition temperature and the prediction method of hardness of glass, it can reduce the test cost to large-scale sample, reduce the waste on the time and damage to sample itself, can be to glass Accurate prediction of transition temperature and hardness provides important support for the design of glass composition and performance.

In order to achieve the above object, the present invention adopts the following technical solutions.

Use the microstructure characterization method to obtain the coordination of each network former x ₁ , x ₂ , x ₃ ... x _n that varies with the chemical composition at room temperature, and record the content f corresponding to the coordination of each network former ₁ , f ₂ , f ₃ ... f _n , the calculation of the glass unit network former coordination C is expressed as:

A method for predicting transition temperature and hardness of glass, characterized in that it comprises the following steps:

(1) Glass structure information detection

Use the microstructure characterization method to obtain glass microstructure information at room temperature, that is, the coordination of each network former x ₁ , x ₂ , x ₃ ... x _n that varies with the chemical composition, and record the coordination with each network former The corresponding content f ₁ , f ₂ , f ₃ ...f _n of the position condition, the formula for calculating the coordination C of the glass unit network former is:

$\mathrm{<span\; class="notranslate">\; C</span>}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; \&lsqb;</span>\underset{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\overset{\mathrm{<span\; class="notranslate">\; no</span>}}{<span\; class="notranslate">\; \&Sigma;</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 2</span>}{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}<span\; class="notranslate">\; \&rsqb;</span><span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span>$

In the formula, f _O and M respectively represent the content of oxygen atoms in the glass raw material and the total number of glass atoms;

(2) Calculation of glass transition temperature

A sample of the same kind is tested for the coordination C ₁ of the network former and the transition temperature T _g1 of the glass, and based on the change relationship between the viscosity of the glass and the temperature, the viscosity corresponding to the transition temperature of the glass and the step (1) to obtain the glass microscopic The relationship between the structure and the theoretical calculation model of the transition temperature T _g of the glass is established, and the calculation formula is:

${\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; \&times;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; C</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span>$

In the formula:

T _g1 represents the transition temperature of the known sample glass,

C represents the coordination of the unit network former,

C ₁ means known sample network former coordination;

(3) Calculation of the linear change value of the coordination between the hardness and the glass microstructure

Use a hardness meter to measure the hardness values H ₁ , H ₂ ... H _n of the glass sample, and obtain the linear change value L of the hardness and the coordination of the glass microstructure obtained in step (1), and the calculation formula is:

$\mathrm{<span\; class="notranslate">\; L</span>}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; no</span>}}\frac{{\mathrm{<span\; class="notranslate">\; h</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}}}{{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}}}}{\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ;</span>$

In the formula:

C _n represents the network former coordination that changes with the chemical composition, when n=1, it is a sample of the same kind described in step (2) that carries out the network former coordination C ₁ ;

(4) Calculation of glass hardness and network former structure chain dimension

According to the dimensions of the glass network structure chain, combined with the linear change relationship between the test hardness value calculated in step (3) and the coordination of the glass microstructure, the calculation formula for the glass hardness H is established:

H=L×(C-d)(4),

In the formula, H represents the glass hardness; L represents the linear change value; d represents the dimension of the glass unit network forming body structure chain;

The formula for calculating the structural chain dimension d of the glass unit network forming body is:

$\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; =</span>\underset{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\overset{\mathrm{<span\; class="notranslate">\; no</span>}}{<span\; class="notranslate">\; \&Sigma;</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\frac{{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 8</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span>$

In the formula, if a certain network former coordinates x _n >4, then this item is expressed as 3f _n .

Further, before the step (1), it includes a test step of conducting a network former coordination _C1 and a glass transition temperature T _g1 on a sample of the same kind.

Further, the microstructure characterization method described in step (1) includes nuclear magnetic resonance, Raman spectroscopy, infrared spectroscopy, X-ray photoelectron spectroscopy, and X-ray absorption fine structure spectroscopy.

Further, step (2) also includes: using the glass unit network to form body coordination to calculate the degree of freedom F of the atoms in the glass structure in three-dimensional space, the calculation formula is:

F=3-C(5);

The degree of freedom of the atoms in the glass structure in three-dimensional space is associated with the glass structure entropy S, and its calculation formula is:

S=FnBlnΩ(6),

In the formula:

n represents the number of atoms in the glass structure,

B represents the Boltzmann constant of the glass structure,

Ω represents the degree of configuration change of atomic degrees of freedom in the glass structure.

Further, the entropy value of glass structure is used to express the viscosity η of glass, and its expression is:

$\mathrm{<span\; class="notranslate">\; lg</span>}\mathrm{<span\; class="notranslate">\; \&eta;</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; lg\&eta;</span>}}^{<span\; class="notranslate">\; \&prime;</span>}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; \&mu;</span>}}{\mathrm{<span\; class="notranslate">\; T</span>}\mathrm{<span\; class="notranslate">\; S</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 7</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span>$

In the formula, η' represents the viscosity of glass at infinite temperature,

μ represents the thermodynamic constant of glass at infinite temperature,

T represents the temperature of the glass at infinite temperature;

The viscosity η' of the glass at infinite temperature is 10 ^-5 Pa·s, and the viscosity η of the glass can be considered as 10 ¹² Pa·s. Substituting it into the expression (3)～expression (6), the predicted glass Calculation model of transition temperature.

The positive effects of the transition temperature of the glass of the present invention and the prediction method of hardness are:

(1) It can accurately predict the transition temperature and hardness of glass, especially for glass compositions with unknown properties.

(2) The number of damaged glass samples to be tested can be greatly reduced, the test efficiency of glass performance can be improved, the cost can be reduced, and the test time can be shortened.

(3) The operation is simple, and the performance of the glass can be corrected without a large number of thermodynamic and kinetic parameters required by the traditional method.

Description of drawings

Fig. 1 is a flow chart of the method for predicting the transition temperature and hardness of the glass of the present invention.

Fig. 2 is a comparison chart of the transition temperature and hardness of the 10Na ₂ O-35SiO ₂ -55P ₂ O ₅ (mole percent) glass between the tested and predicted values.

Specific implementation method

The specific implementation of the method for predicting the transition temperature and hardness of the glass of the present invention is provided below in conjunction with the accompanying drawings, and two examples are provided, but it should be pointed out that the implementation of the present invention is not limited to the following embodiments.

See Figure 1. A method for predicting transition temperature and hardness of glass, comprising the following steps:

First test a similar sample for network former coordination C ₁ and glass transition temperature T _g1 , and then perform the following prediction steps.

(1) Glass structure information detection

Using microstructural characterization methods including nuclear magnetic resonance, Raman spectroscopy, infrared spectroscopy, X-ray photoelectron spectroscopy, and X-ray absorption fine-structure spectroscopy to obtain glass microstructure information at room temperature, that is, each network former that varies with chemical composition x ₁ , x ₂ , x ₃ ... x _n coordination, record the content f ₁ , f ₂ , f ₃ ... f _n corresponding to the coordination of each network former, and calculate the glass unit network former coordination The formula for bit C is:

$\mathrm{<span\; class="notranslate">\; C</span>}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; \&lsqb;</span>\underset{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\overset{\mathrm{<span\; class="notranslate">\; no</span>}}{<span\; class="notranslate">\; \&Sigma;</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 2</span>}{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}<span\; class="notranslate">\; \&rsqb;</span><span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span>$

In the formula, f _O and M represent the content of oxygen atoms in the glass raw material and the total number of glass atoms, respectively.

(2) Calculation of glass transition temperature

A sample of the same kind is tested for the coordination C ₁ of the network former and the transition temperature T _g1 of the glass, and based on the change relationship between the viscosity of the glass and the temperature, the viscosity corresponding to the transition temperature of the glass and the step (1) to obtain the glass microscopic The relationship between the structure and the theoretical calculation model of the transition temperature T _g of the glass is established, and the calculation formula is:

${\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; \&times;</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; C</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span>$

In the formula: T _g1 represents the transition temperature of the known sample glass, C represents the coordination of the unit network former, and C ₁ represents the coordination of the known sample network former.

(3) Calculation of the linear change value of the coordination between the hardness and the glass microstructure

Use a hardness meter to measure the hardness values H ₁ , H ₂ ... H _n of the glass sample, and obtain the linear change value L of the hardness and the coordination of the glass microstructure obtained in step (1), and the calculation formula is:

$\mathrm{<span\; class="notranslate">\; L</span>}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; no</span>}}\frac{{\mathrm{<span\; class="notranslate">\; h</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}}}{{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}}}}{\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ;</span>$

In the formula: C _n represents the network former coordination that varies with the chemical composition, and when n=1, it is the network former coordination C ₁ of a sample of the same kind described in step (2).

The step (2) also includes: using the glass unit network to form body coordination to calculate the degree of freedom F of atoms in the glass structure in three-dimensional space, and the calculation formula is:

F=3-C(5).

The degree of freedom of the atoms in the glass structure in three-dimensional space is associated with the glass structure entropy S, and its calculation formula is:

S=FnBlnΩ(6),

In the formula: n represents the number of atoms in the glass structure, B represents the Boltzmann constant of the glass structure, and Ω represents the degree of configuration change of the atomic degree of freedom in the glass structure.

The entropy value of described glass structure is used to express the viscosity η of glass, and its expression is:

$\mathrm{<span\; class="notranslate">\; lg</span>}\mathrm{<span\; class="notranslate">\; \&eta;</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; lg\&eta;</span>}}^{<span\; class="notranslate">\; \&prime;</span>}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; \&mu;</span>}}{\mathrm{<span\; class="notranslate">\; T</span>}\mathrm{<span\; class="notranslate">\; S</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 7</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span>$

In the formula, η' represents the viscosity of the glass at an infinite temperature, μ represents the thermodynamic constant of the glass at an infinite temperature, and T represents the temperature of the glass at an infinite temperature.

The viscosity η' of the glass at infinite temperature is 10 ^-5 Pa·s, and the viscosity η of the glass can be considered as 10 ¹² Pa·s. Substituting it into the calculation formula (3) ~ calculation formula (6), the predicted glass Calculation model of transition temperature.

(4) Calculation of glass hardness and network former structure chain dimension

According to the dimensions of the glass network structure chain, combined with the linear change relationship between the test hardness value calculated in step (3) and the coordination of the glass microstructure, the calculation formula for the glass hardness H is established:

H=L×(C-d)(4),

In the formula, H represents the glass hardness; L represents the linear change value; d represents the structural chain dimension of the glass unit network forming body.

Described step (4) also comprises the dimension d of glass network structure chain, and its calculation formula is:

$\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; =</span>\underset{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\overset{\mathrm{<span\; class="notranslate">\; no</span>}}{<span\; class="notranslate">\; \&Sigma;</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\frac{{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 8</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span>$

In the formula, if a certain network former coordinates x _n >4, then this item is expressed as 3f _n .

Two application examples of the method for predicting the transition temperature and hardness of the glass of the present invention are provided below.

Application Example 1

Glass samples prepared by the melting cooling method are then used to predict the transition temperature and hardness of the glass.

The glass sample is crushed and ground to obtain glass powder, and the transition temperature of the glass is tested: the heating rate is 10K/min, nitrogen atmosphere, and the results are calculated by the comparative prediction method.

Mirror polish the surface of the glass sample, use a Vickers hardness tester, the pressure is 0.98N, stay on the surface of the glass sample for 10s, and then observe the crack size under the microscope, the crack should be less than 100nm, and obtain the hardness value of the glass sample, which can be used in the model The calculation results of the establishment and comparison of forecasting methods.

The glass sample 10Na ₂ O-35SiO ₂ -55P ₂ O ₅ (mole percent) was characterized by structural coordination to obtain a hexacoordinated silicon-oxygen structure with a network former coordination x _n and f _n content of 6.8%, 17.4% Four-coordinated silicon-oxygen structure, 62.0% three-coordinated phosphorus-oxygen structure and 13.8% two-coordinated phosphorus-oxygen structure. Through the calculation formula ( ₁ ) of the prediction method of the present invention, the value of the unit network former coordination C at high temperature is 2.34, and the unit network former coordination _C1 of pure _P2O5 and the transition temperature T _g1 of the glass are obtained. are 3.00 and 590K respectively, and substituting C, C ₁ , and T _g1 into the calculation formula (2) of the prediction method of the present invention, the transition temperature T _g of the glass obtained is 695K, and the error with the test value of 689K is only <1%. The result is shown in the figure 2.

Combining the hardness test values of some glass samples with similar components, the relationship between the hardness and structural coordination of sodium _{phosphosilicate} glass _is obtained. Formula (3) calculates that the unit network former coordination C is 3.02 at room temperature, and the network former coordination x _n and its f _n content are obtained according to the structural coordination characterization, and the glass is obtained by calculation formula (8) of the prediction method of the present invention The dimension d of the network structure chain is 2.55, and L, C, and D are respectively substituted into the calculation formula (2) of the prediction method of the present invention to obtain a glass hardness of 4.88GPa, which is consistent with the test value of 4.87～4.89GPa, and the result is shown in Figure 2 Show.

Application Example 2

The transition temperature and hardness of the glass are predicted by using the glass sample prepared by the melting and cooling method (preparation for the prediction is the same as in Example 1).

Using structural coordination characterization of the glass sample 33K ₂ O-33B ₂ O ₃ -34P ₂ O ₅ (mole percent), the four-coordinate boron-oxygen structure with the network former coordination x _n and f _n content of 33% respectively, 49.8% of the three-coordinated phosphorus-oxygen structure and 17.2% of the two-coordinated phosphorus-oxygen structure. Through the calculation formula ( ₁ ) of the prediction method of the present invention, the value of the unit network former coordination C at high temperature is 1.86, and the unit network former coordination _C1 of pure _P2O5 and the transition temperature T _g1 of the glass are obtained. They are 3.00 and 590K respectively. Substituting C, C ₁ , and T _g1 into the calculation formula (4) of the prediction method of the present invention obtains a glass transition temperature T _g of 657K, which has an error of less than 0.3% from the test value of 655K.

From the results of Examples 1-2, it can be seen that the transition temperature and hardness value of the glass can be well predicted by the prediction method of the present invention.

Claims (3)

1. the transition temperature of glass and a Forecasting Methodology for hardness, is characterized in that, comprise the following steps:

(1) glass structure infomation detection

Microstructure characterization method is adopted at room temperature to obtain glass micromechanism information, that is, with each Network former x of chemical composition change ₁, x ₂, x ₃x _ncoordination situation, record the content f corresponding with often kind of Network former coordination situation ₁, f ₂, f ₃f _n, the formula calculating glass identity network organizator coordination C is:

$C=\&lsqb;\underset{i=1}{\overset{n}{\&Sigma;}}(2x_n-3)f_n{x}_n+2f_O\&rsqb;/M---\left(1\right),$

In formula, f _o, the M respectively content of represention oxygen atom in frit and glass total atom number;

Comprised before described step (1) and Network former coordination C is carried out to a similar sample ₁and the transition temperature T of glass _g1testing procedure;

(2) calculating of glass transformation temperature

Based on the variation relation of glass viscosity and temperature, obtain the relation obtaining glass micromechanism with the viscosity corresponding to the transition temperature of glass and step (1), set up the transition temperature T of glass _gtheoretical calculation model, its computing formula is:

$T_g=\frac{T_{g1}\&times;(3-C_1)}{3-C}---\left(2\right),$

In formula:

T _g1represent the transition temperature of known sample glass,

The coordination of C representation unit Network former,

C ₁represent the coordination of known sample Network former;

(3) calculating of the linear change value of hardness and the coordination of glass phase microstructure

Adopt the hardness number H of Durometer measurements glass sample ₁, H ₂h _n, obtain the linear change value L that hardness and step (1) obtain the coordination of glass phase microstructure, its computing formula is:

$L=\frac{{\&Sigma;}_{i=1}^n\frac{H_n}{C_n}}{n}---\left(3\right);$

In formula:

C _nrepresent the Network former coordination with chemical composition change;

(4) calculating of glass hard (HRC65Yi Shang) and Network former structural chain dimension

According to the dimension of glass network structural chain, the linear changing relation of the tested for hardness value that integrating step (3) calculates and the coordination of glass micromechanism, sets up the computing formula of glass hard (HRC65Yi Shang) H:

H＝L×(C-d)(4)，

In formula, H represents glass hard (HRC65Yi Shang); L represents linear change value; D represents glass identity network organizator structural chain dimension;

The computing formula of described glass identity network organizator structural chain dimension d is:

$d=\underset{i=1}{\overset{n}{\&Sigma;}}\left(1+\frac{x_n}{2}\right)f_n---\left(8\right),$

In formula, certain Network former coordination x _n> 4, then this is expressed as 3f _n.

2. the transition temperature of glass according to claim 1 and the Forecasting Methodology of hardness, it is characterized in that, the Microstructure characterization method described in step (1) comprises nuclear magnetic resonance, Raman spectrum, infrared spectrum, x-ray photoelectron power spectrum, X ray Absorption Fine Structure spectrum.

3. the transition temperature of glass according to claim 1 and the Forecasting Methodology of hardness, it is characterized in that, step (2) also comprises: calculate glass structure Atom at three-dimensional degree of freedom F with the coordination of glass identity network organizator, its computing formula is:

F＝3-C(5)；

Associated with glass structure entropy S-phase in three-dimensional degree of freedom by described glass structure Atom, its computing formula is:

S＝FnBlnΩ(6)，

In formula:

N represents the atom number in glass structure,

B represents the Boltzmann constant of glass structure,

Ω represents the atom degree of freedom change of configuration degree in glass structure.