CN108516684B

CN108516684B - Inorganic bonding glaze and preparation method thereof

Info

Publication number: CN108516684B
Application number: CN201810427597.6A
Authority: CN
Inventors: 李玉平; 马天齐; 郭爱芬; 高应霞; 肖万芬
Original assignee: Hunan University
Current assignee: Suzhou Porcelain Insulator Works Co ltd
Priority date: 2018-05-07
Filing date: 2018-05-07
Publication date: 2021-01-15
Anticipated expiration: 2038-05-07
Also published as: CN108516684A

Abstract

The invention relates to an inorganic bonding glaze and a preparation method thereof, wherein the method comprises the steps of mixing basic glaze, borax and albite, sintering the mixture at 1200-1500 ℃ to prepare a basic glaze melt, and performing water quenching to obtain a basic glaze frit for later use; wherein, the addition amount of the borax is 2 to 6 weight percent of the basic glaze, and the addition amount of the albite is 2 to 8 weight percent of the basic glaze; and (4) mixing the base glaze frit obtained in the step S1 with a crystal nucleus agent, and grinding to obtain the inorganic bonding glaze. The preparation method disclosed by the invention is novel in concept, and the prepared inorganic bonding glaze is high in bonding strength and strong in stability.

Description

Inorganic bonding glaze and preparation method thereof

Technical Field

The invention relates to an inorganic bonding glaze and a preparation method thereof, in particular to an inorganic bonding glaze for bonding an ultrahigh-voltage hollow porcelain insulator and a preparation method thereof.

Background

Along with the continuous improvement of the voltage grade of the power transmission and transformation project, the height of the hollow insulator matched with the power transmission and transformation project is increased, for example, the height of an 800kV porcelain insulator product for a switch reaches 10m or more, and the maximum outer diameter reaches 1100 mm. Under the prior art, the ultra-large porcelain insulator cannot be manufactured in an integral forming and integral firing mode. Generally, the ceramic is formed by sectional molding, sectional firing and finally bonding and combining the sintered ceramic pieces. Organic bonding methods and inorganic bonding methods are two general types of bonding methods.

Organic bonding, i.e., bonding the porcelain insulator components with a resin. The organic adhesives commonly used are epoxy resins and phenolic resins. The former is mainly prepared from epoxy resin base material, accelerator, curing agent, filler and diluent. The adhesive has good adhesion and functionality, simple process and low cost, and thus, the adhesive is widely applied. The research and development of the epoxy resin are continuously deepened, and the performance of the epoxy resin is continuously improved; the latter is a general term for resins formed from phenols and aldehydes under the action of catalysts, and has the advantages of water resistance, weather resistance, temperature resistance, high adhesive strength and the like. With the continuous development work, the toughness, durability and electrical performance of the phenolic resin are continuously optimized. But organic bonding still has disadvantages: the aging, brittleness and elasticity can not reach the ideal value, and the electrical property is difficult to ensure. Therefore, inorganic bonding is often used for manufacturing large insulators. The organic bonding operation is convenient, and the technology is mature.

Inorganic bonding: i.e. the glaze is used to bond the ceramic parts. The inorganic bonding glaze and the porcelain piece have stable chemical properties, excellent temperature resistance and oil resistance, better aging resistance, lower cost, economy and environmental protection, generally do not generate the aging problem, and the mechanical strength and the electrical performance of the product can not be reduced along with the time. After the inorganic bonding glaze is fired for the second time, the glaze melt can permeate into the upper and lower porcelain pieces to form a stronger connection effect. The large porcelain insulator bonded by the method has high mechanical strength, small form and position tolerance and particularly good ageing resistance, and is popular.

The key point of realizing inorganic bonding is that the inorganic bonding glaze is designed, and the inorganic bonding glaze is required to have good electrical property, mechanical property, cold and hot properties, blank glaze adaptability and the like, and particularly, the inorganic bonding glaze is required to have good bonding property. Secondly, the bonding part must be finely processed, so that the upper and lower energy-saving parts of the bonding surface are closely matched, and the bonding glaze can be well accommodated, so that the glaze melt formed at high temperature can be uniformly spread on the bonding surface. The glazing zone is a relatively enclosed space. In this case, bubbles generated in the bonding glaze may be difficult to discharge and may affect the quality of bonding.

Some people have done related work in preparing inorganic bonding glaze. For example, CN1075943A, CN101439988A, CN102757258A, etc. all disclose some methods for preparing inorganic bonding glaze. Zhang Xitang (2005) discusses large porcelain bushingThe key process of inorganic bonding forming is that the manufacture, the loading and the sintering of a blank, the grinding of a bonding surface and the like all have important influences on the bonding qualified rate in the bonding process. In the above-mentioned several publications, raw glaze is used for inorganic bonding. The pigment in the glaze is separated from the basic glaze material, the pigment is synthesized in advance, the synthesized pigment is used as a glaze raw material, other basic glaze raw materials are added, and the mixture is ground together to prepare the inorganic bonding glaze. The Yunxianxia, Yanhai, Yanxia (2013), etc. propose to increase the binding strength by reducing the generation of gas phase in glaze, and they also emphasize that the calcined clinker, such as aged great, aged talc, etc. is selected as much as possible to reduce the discharge of volatile matter during firing, but they also use dolomite (CaMg (CO)₃)₂) Such raw materials capable of generating a large amount of gas; they also add ZrO during glazing₂Micro powder is used for improving the strength of the glaze; although some improvements are made, most of the inorganic bonding glaze still belongs to the category of raw glaze from the prior literature, and bubbles are still generated in the firing process.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides an inorganic bonding glaze with high bonding strength and stability and a preparation method thereof.

In order to solve the technical problems, the technical scheme of the invention is as follows: a preparation method of an inorganic bonding glaze comprises the following steps:

s1, mixing the basic glaze, borax and albite, sintering at 1200-1500 ℃ to obtain a basic glaze melt, and water quenching to obtain a basic glaze frit for later use;

wherein, the addition amount of the borax is 2 to 6 weight percent of the basic glaze, and the addition amount of the albite is 2 to 8 weight percent of the basic glaze;

s2, mixing the base glaze clinker obtained in the step S1 with a nucleating agent, and grinding to obtain an inorganic bonding glaze;

wherein the addition amount of the crystal nucleating agent is 1 to 5 weight percent of the base glaze frit.

The bonding glaze of the invention is based on mature electric porcelain glaze, some functional components are added, and the prepared basic glaze frit is used as a main body. The basic glaze frit is combined with a crystal nucleus agent and ground to form a brand new inorganic bonding glaze. The basic glaze is made into the basic glaze frit, so that the volatility of the glaze is eliminated, bubbles which are difficult to eliminate and generated in the subsequent firing process of the bonding glaze can be effectively avoided, the bonding part is compact and reliable, and the bonding strength is improved; the addition of the crystal nucleating agent can enable the inorganic bonding glaze to form partial microcrystals under high temperature conditions (in the process of sintering after bonding), and can improve the strength of the glaze glass, thereby improving the bonding strength.

Borax and albite mainly reduce high-temperature viscosity, glass is easy to melt, and the expansion coefficient of the glass can be slightly increased.

Further, in step S2, the base glaze frit obtained in step S1, a crystal nucleus agent and a coloring material are mixed and ground to obtain an inorganic bonding glaze

Further, the preparation method of the pigment comprises the following steps: mixing a basic toner, magnesium oxide and borax, preserving heat for 1-3 hours at 900-1350 ℃, cooling, grinding, sequentially pickling and cleaning, and drying to obtain a pigment;

wherein the addition amount of the magnesium oxide is 1-8 wt% of the basic toner, and the addition amount of the borax is 1-10 wt% of the basic toner.

Further, in step S1, the firing temperature is 1400-.

Further, the base colorant may be a commercially available colorant.

Further, the basic color agent comprises ferric oxide, chromic oxide and manganese dioxide, and is a brown color agent, and the specific proportion of the color agent can be selected according to actual needs.

Further, the basic glaze is the electric porcelain glaze, the formula of the basic glaze can be directly determined according to the formula of the electric porcelain glaze, and specifically, the formula of the electric porcelain basic glaze without coloring elements can be designed by adopting a method of directly removing coloring elements of the original electric porcelain glaze or replacing the original raw materials with other raw materials with low coloring element content; the common original electric porcelain glaze can also be directly used as the basic glaze of the invention.

Further, the basic glaze comprises, by mass, 10-18 parts of feldspar powder, 20-30 parts of quartz powder, 2-6 parts of field Master soil or Hubei mud, 8-15 parts of porcelain powder, 2-8 parts of calcite, 1-3 parts of talcum powder, 0-3 parts of barium carbonate and 0-2 parts of spodumene.

The crystal nucleus agent comprises at least one of zinc oxide, zirconium silicate, fluorite and kaolin.

An inorganic bonding glaze is prepared by the preparation method.

When the inorganic bonding glaze is used for bonding a plurality of hollow porcelain insulators, two end faces of the hollow porcelain insulators to be bonded can be ground and processed into mutually matched grooves and convex faces, wherein the surface to be bonded of the lower insulator is an upward-opening V-shaped groove, and the surface to be bonded of the upper porcelain insulator is a reversed V-shaped convex face with a downward pointed top; then positioning the processed first section of porcelain insulator at the lower part in a bottom plate of a bell jar kiln with a kiln body removed, and filling the refined inorganic bonding glaze powder or bonding glaze paste into a V-shaped groove of the hollow porcelain insulator at the lower part, wherein the glaze powder or the glaze paste is at least added to the depth of the V-shaped groove above 2/3; hoisting the upper porcelain insulator to be bonded on the first section of porcelain insulator, and accurately positioning the inverted V-shaped convex surface into the inverted V-shaped groove; and (3) slightly rotating the upper hollow porcelain insulator to enable the two hollow porcelain insulators to be coaxially vertical, uniformly distributing glaze powder or glaze paste on the surface to be bonded, and firing (see fig. 2 and fig. 3).

The preparation method disclosed by the invention is novel in concept, and the prepared inorganic bonding glaze is high in bonding strength and strong in stability.

Drawings

Fig. 1 is an SEM image of the bonding interface when the inorganic bonding glaze of example 1 is used for bonding, wherein, (a) is a 1000-fold enlarged view, (b) is a 10000-fold enlarged view, (c) is a 600-fold enlarged view, and (d) is a 2000-fold enlarged view.

FIG. 2 is a photograph showing the mounting and burning of a test piece bonded with the inorganic bonding glaze of the present invention.

FIG. 3 is a photograph showing the outer shape of a test piece bonded with the inorganic bonding glaze of the present invention.

Detailed Description

The present invention will be described in detail with reference to examples.

Example 1

A preparation method of an inorganic bonding glaze comprises the following steps:

in this embodiment, the electrical porcelain glaze is used as the base glaze, and first, the composition characteristics of the electrical porcelain glaze are analyzed. The electric porcelain glaze has good working properties such as good suspension property and sufficient uniform dispersibility, so that the electric porcelain glaze can be smoothly adsorbed by a dry blank to form a uniform glaze layer during glazing, can be smoothly matured at a high temperature, forms a firm blank glaze binding layer, and can improve the mechanical strength of the electric porcelain.

For example, the brown glaze of certain electroceramics manufacturing company, the 5# brown glaze formulation is especially mature, and on the basis of the brown glaze formulation, the formulations are slightly adjusted to form 6# and 7# (see table 1). The main raw materials include feldspar powder, quartz sand, field soil, blank mud, Master Tian, porcelain powder, calcite, talcum powder, oxides of iron, chromium and manganese, barium carbonate and the like. The iron oxide in the brown glaze comes from the field, and a small amount of iron oxide is also added in the No. 7 formula.

TABLE 1 brown glaze ratio (wt%) of three electric porcelain

During material preparation, the raw materials are accurately weighed and ground by a ball mill for 24 hours, and the screen residue of 3 glaze slurry materials on a 320-mesh screen is respectively 0.037%, 0.025% and 0.031%. Applying the glaze layer on an electric porcelain test strip, wherein the thickness of the glaze layer is about 0.3mm, and keeping the temperature at 1245 ℃ for 2 h. After cooling, the flexural strength and the expansion coefficient of the porcelain test strips were determined (Table 2). MnO in terms of amount of colored oxide₂And Cr₂O₃The amount of the iron oxide is the same, and a little Fe is additionally added in the brown glaze in No. 7₂O₃Can precipitate red alpha-Fe with more stable color in glaze₂O₃。

TABLE 2 chemical composition (wt%) and physical properties of the brown glaze for three electrotechnical porcelain

The working idea of the invention is as follows: the inorganic bonding glaze is manufactured by modifying the proven effective and mature formula of the electric porcelain glaze in the production. The method is that the components and the functions of the existing glaze are analyzed, then the glaze is respectively processed, and then the glaze suitable for inorganic bonding is prepared.

The electric porcelain brown glaze can be divided into three parts: basic glaze as the main part of the glaze, color oxide mainly comprising iron oxide, chromium oxide, manganese oxide and the like, and other functional components. The characteristics of the above-mentioned several glazes were analyzed and divided into the above-mentioned three parts. Firstly, the color development oxide is removed from the glaze formula, the main raw material containing the color development oxide is replaced by other raw materials (in the example, the field is replaced by the raw material of eastern castle mud produced by the Hunan carignan Ling in the same amount, and the components of the eastern castle mud and the field are listed in the table 3), and the rest is the basic glaze with the color development elements removed.

TABLE 3 chemical composition of Tiantu and Dongpo mud (wt%)

And adding 3 parts of albite and 3 parts of borax into the basic glaze, keeping other raw materials unchanged, uniformly mixing, melting at the temperature of above 1450 ℃, and performing water quenching to prepare a basic glaze frit (hereinafter referred to as frit for short) for later use.

According to the proportion of coloring elements removed from the original glaze formula, coloring oxides are used as raw materials, and a solid-phase reaction method is used for synthesizing the coloring material. In this example, analytically pure iron oxide, manganese oxide and chromium oxide were used as raw materials, a small amount of magnesium oxide and 3% borax were added, and the color former was synthesized by solid phase reaction at 1200 ℃. And after cooling, crushing, sieving, acid washing and drying the synthesized toner to obtain the synthesized spinel brown toner. The brown pigment has a certain color variation range, and 2 formulas of the color agents are designed according to the proportion of the color-developing oxides in the 3 glazes (see table 4), so that 2 kinds of pigments are synthesized. The synthesized colorants may be used alone or in combination.

TABLE 4 color base material ratio (%)

Color base material formula	Manganese oxide	Iron oxide	Chromium oxide
				No01	75	12.5	12.5
No02	68.6	11.8	19.6

The prepared basic glaze frit, the synthesized pigment and the zinc oxide and the zirconium oxide which mainly play the role of a crystal nucleating agent are taken as functional components to prepare the inorganic bonding glaze which has certain crystallization capacity and can form a continuous middle layer on the surface of a ceramic room.

In this example, 90% of base glaze clinker, 8% of synthetic brown colorant and 1% of zinc oxide and zircon are weighed, and then ground in a ball (sand) mill using zirconium oxide or aluminum oxide as grinding body for about 12 hours, and passed through 320 mesh sieve, the residue on sieve is controlled not to be greater than 0.5%, so that a new inorganic bonding glaze with similar components to the original electric porcelain glaze is obtained.

The inorganic bonding glaze is prepared by adopting the fritted glaze and the synthetic coloring agent, and has three main reasons, namely, bubbles which are difficult to remove can be avoided in the melting process of the glaze layer, and the bubbles can be avoided when the coloring oxide is at high temperature by adopting the synthetic pigment; thirdly, a crystal nucleus agent is added, so that some crystal phases can be precipitated in the glaze layer, and the bonding strength can also be improved. In addition, the mature electric porcelain glaze used in production is transformed into the inorganic bonding glaze, so that the stability of the property of the glaze can be ensured, and the success rate of inorganic bonding is increased. The following is a scanning electron microscope photograph of the hollow porcelain insulator bonded by inorganic bonding glaze powder, and the photograph shows that the glaze and the porcelain body are perfectly combined and a crystal phase begins to be separated out from the glaze. The bending load (breakage) of the obtained product reaches 602 kN.m, which shows that the bonding effect is excellent.

Example 2

To discuss the effect of the glaze powder or the glaze paste to which the inorganic glaze was applied, the two forms of inorganic glaze were subjected to adhesion tests in porcelain test bars having the same plane interface. The cut and the burning of the test strip are seen in the picture.

The dry method of direct glazing powder and the wet method of direct glazing paste are respectively adopted for glazing. When the glaze paste is prepared, a small amount of silica sol is added to enhance the bonding capability of the glaze paste. The flexural strength was measured after firing to evaluate the adhesion (Table 5).

TABLE 5 breaking strength (MPa) of flat-notched porcelain test strip bonded by dry method and wet method

Glazing method	1	2	3	4	5	6	7	Mean value of
									Dry process	70	75	73	69	75	65	68	71
Wet strength	86	84	80	79	77	84	90	83

From the interface condition of the glaze, the dry bonding section has more and larger bubbles, while the wet bonding section has more but smaller bubbles generally, i.e. the bonding glaze at the interface of the wet bonding test bar is more uniform than the dry bonding, and the process is easier to control, so the bonding effect by using the glaze paste is better than the bonding effect by directly using the glaze powder.

The foregoing examples are set forth to illustrate the present invention more clearly and are not to be construed as limiting the scope of the invention, which is defined in the appended claims to which the invention pertains, as modified in all equivalent forms, by those skilled in the art after reading the present invention.

Claims

1. A preparation method of an inorganic bonding glaze for bonding a hollow porcelain insulator is characterized by comprising the following steps:

wherein, the addition amount of the borax is 2 to 6 weight percent of the basic glaze, and the addition amount of the albite is 2 to 8 weight percent of the basic glaze; the basic glaze comprises 10-18 parts of feldspar powder, 20-30 parts of quartz powder, 2-6 parts of Master Tian soil or Hubei mud, 8-15 parts of porcelain powder, 2-8 parts of calcite, 1-3 parts of talcum powder, 0-3 parts of barium carbonate and 0-2 parts of spodumene by weight;

s2, mixing the base glaze clinker obtained in the step S1 with a nucleating agent and a pigment, and grinding to obtain inorganic bonding glaze;

wherein the addition amount of the crystal nucleating agent is 1-5 wt% of the base glaze frit, and the crystal nucleating agent consists of zinc oxide and zircon; the preparation method of the pigment comprises the following steps: mixing a basic toner, magnesium oxide and borax, preserving heat for 1-3 hours at 900-1350 ℃, cooling, grinding, sequentially pickling and cleaning, and drying to obtain a pigment; wherein the addition amount of the magnesium oxide is 1-8 wt% of the basic toner, and the addition amount of the borax is 1-10 wt% of the basic toner; the basic color agent comprises ferric oxide, chromium oxide and manganese dioxide.

2. An inorganic bonding glaze, characterized by being produced by the production method according to claim 1.