WO2022041785A1 - Ground coat glaze of stainless steel enamel plate, and preparation method therefor and application thereof - Google Patents

Abstract

A ground coat glaze of a stainless steel enamel plate, comprising the following components in mass percentage: 30-38% of SiO2; 15-19% of B2O3; 6-10% of Al2O3; 1-2% of TiO2; 1-4% of BaO; 14-19% of Na2O; 5-10% of K2O; 0.1-0.6% of MgO; 2-4% of P2O5; 0.2-0.8% of ZnO; 0.1-0.3% of Cr2O3; 0.4-0.8% of CuO; 0.3-0.9% of CoO; 0.7-1.2% of NiO; and 0.8-1.3% of MnO2. The stainless steel enamel plate prepared from the glaze at a low sintering temperature has good adhesion, and the obtained enamel surface is smooth and fine.

Description

Bottom glaze for stainless steel enamel plate and preparation method and application thereof technical field

The invention relates to the field of enamel material preparation, in particular to a bottom glaze glaze of a stainless steel enamel plate and a preparation method and application thereof.

Background technique

Enamel plate refers to a composite material in which inorganic vitreous materials are condensed on the base steel plate by melting and firmly combined with the steel plate. Enamel coating on the surface of the steel plate can prevent the steel plate from rusting, so that the steel plate will not form an oxide layer on the surface when it is heated and can resist the erosion of various liquids. Enamel products have excellent properties such as high hardness, high temperature resistance, wear resistance, insulation, safety and non-toxicity, and easy washing and cleaning, and the enamel layer can also give the products a beautiful appearance. Inner and outer walls, decorative wall panels for tunnels, sterile operating room walls, pedestrian underpass wall panels and heat exchangers, etc.

At present, the enamel plate is generally made of low carbon steel plate, but once the edge and corner of the low carbon steel enamel plate explodes, the bottom plate exposed to the external environment will be rusted. Furthermore, when it is used as an outer curtain wall, due to the The larger perforation rate pursued by the exterior curtain wall decoration will also cause the problem of plate deformation. These problems have been the main reasons for limiting the application of mild steel enamel panels in exterior curtain wall decoration. Compared with ordinary low-carbon steel plates, stainless steel has the properties of corrosion resistance, high strength, steel deformation is not easy to break, and environmental protection, and stainless steel has good ductility and toughness, suitable for harsh environments (humidity, acid and alkali and other indoor and outdoor environments) use. Therefore, replacing low carbon steel with stainless steel base material will be able to solve some problems existing in the current exterior curtain wall decoration.

Therefore, how to provide a stainless steel enamel plate in which the base glaze is firmly combined with the stainless steel and has excellent chemical properties is a technical problem that needs to be solved urgently in the art.

SUMMARY OF THE INVENTION

In view of the above problems, the present invention achieves the goals of good enamel adhesion and high quality of the porcelain surface by improving the formulation and preparation process of the enamel layer bottom glaze glaze.

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

A base glaze for a stainless steel enamel plate, in terms of mass percentage, comprising the following components: in terms of mass percentage, including the following components: SiO ₂ 30-38%; B ₂ O ₃ 15-19%; Al ₂ O ₃ 6-10%; _{TiO2 1-2} %; BaO 1-4%; Na2O 14-19%; K2O _5-10 %; MgO 0.1-0.6%; _{P2O5 2-4} %; ZnO 0.2-0.8%; _Cr2O3 0.1-0.3%; _CuO 0.4-0.8%; CoO 0.3-0.9%; NiO 0.7-1.2% and _MnO2 0.8-1.3%.

There are two types of stainless steel enamel glaze: bottom glaze and top glaze. The bottom glaze needs to be combined with stainless steel. How to make the bottom glaze and stainless steel achieve high adhesion is the technical difficulty of stainless steel enamel plates.

In the glaze provided by the present invention, SiO ₂ is the main component and is the main glass network forming body. The higher the amount of SiO ₂ in the glaze, the higher the firing temperature. Increasing the content of SiO ₂ in the range of 30-38% can improve the mechanical strength and hardness of the glaze, as well as the gloss, chemical stability and thermal stability of the glaze.

The B ₂ O ₃ in the glaze provided by the present invention is not only a solvent for the enamel but also a network former of the enamel, which can promote the formation of a glass phase at a low temperature stage. The increase of B ₂ O ₃ content will increase the mechanical strength and abrasion resistance of the enamel. B ₂ O ₃ has a good fluxing effect, which can reduce the softening temperature, viscosity, surface tension and expansion coefficient of the enamel, which is beneficial to the melting of metal oxides and the formation of adhesion.

Al ₂ O ₃ in the glaze provided by the present invention is an intermediate oxide, which can not only combine with silicon dioxide, but also combine with alkaline oxides. It can not only improve the vitrification ability of the enamel, but also inhibit the crystallization, and can significantly improve the elasticity, hardness and chemical stability of the glaze, and improve the resistance to chemical corrosion.

The _TiO2 in the glaze provided by the present invention is to increase the opacity, acid resistance and luster of the enamel. Due to the good opacity, the enamel only needs to be coated with a thin layer, so this porcelain layer has high thermal stability, impact resistance and flexural strength, and has good chemical stability; at the same time, TiO ₂ improves the luster of the enamel. , make the surface of enamel products more smooth and delicate.

BaO in the glaze provided by the invention is a fluxing agent, barium has the largest ionic radius among alkali metals, the strongest alkalinity is also the best fluxing effect among alkali metal oxidations, and can also improve the anti-organic resistance of the glaze. Acid corrosion ability.

K ₂ O and Na ₂ O in the glaze provided by the invention are strong fluxes of the glaze, which can significantly reduce the melting temperature and high temperature viscosity of the glaze, increase the refractive index of the glaze, and thereby improve the gloss of the glaze. K ₂ O and Na ₂ O have low melting points. During the melting process of enamel, they are prone to chemical reaction with SiO ₂ , and the reaction will release a lot of heat, thereby reducing the external heating temperature and reducing the viscosity at high temperature.

In the present invention, MgO is also a fluxing agent of the glaze, which can not only reduce the melt viscosity, but also reduce the expansion coefficient of the glaze, reduce the cracking of the glaze surface, and improve the quality of the porcelain surface.

The P ₂ O ₅ in the glaze provided by the invention can increase the opacity of the glaze, increase the reflection coefficient of the porcelain layer, and cooperate with titanium dioxide to jointly improve the chemical stability of the glaze.

The ZnO in the glaze provided by the invention can play a good fluxing effect in a large range, reduce the expansion coefficient of the glaze, and improve the gloss. However, excessive use will cause the glaze to crystallize and cause the glaze to lose its permeability. Therefore, the mass fraction of zinc oxide is selected to be 0.2-0.8%.

The Cr ₂ O ₃ in the glaze provided by the invention can improve the chemical stability and high temperature resistance performance of the enamel, and at the same time can also be beneficial to the formation of the stainless steel enamel adhesion in the invention.

CuO, CoO, NiO and MnO ₂ in the glaze provided by the present invention are adhesives, and the four adhesives have an interaction relationship, and their interaction can react with iron, so that the enamel penetrates into the surface layer of the steel plate and promotes the enamel glaze Infiltrating the stainless steel surface at high temperature promotes the dissolution of iron and iron oxide, and controls the oxidation conditions of the interface, which is conducive to the formation of a more uniform bubble structure in the porcelain layer and a good adhesion between the bottom glaze and the stainless steel.

Preferably, the bottom glaze of the above-mentioned stainless steel enamel plate, in terms of mass percentage, includes the following components: SiO ₂ 36.39%; B ₂ O ₃ 17.87%; Al ₂ O ₃ 7.06%; TiO ₂ 1.15%; BaO 2.79% ; Na ₂ O 17.59%; K ₂ O 9.96%; MgO 0.18%; P ₂ O ₅ 2.95%; ZnO 0.57%; Cr ₂ O ₃ 0.15% _; %.

The invention also discloses a method for preparing the base glaze of the above-mentioned stainless steel enamel plate, comprising the following steps: (1) mixing the components according to the proportion;

(2) put the mixture into the high temperature furnace to melt;

(3) put into water after melting and quench to form enamel frit;

(4) The enamel frit is turned into a ball mill and ground to form a glaze.

Preferably, in the step (2), the melting temperature is 1000-1200° C., and the enamel frit is ground and passed through a 70-90 mesh sieve.

A stainless steel enamel plate, comprising a stainless steel substrate, a bottom glaze and a top glaze; the bottom glaze and the top glaze are sequentially attached to the stainless steel substrate; and the raw material of the bottom glaze is any one of claims 1-2 The bottom glaze glaze.

The surface glaze formula in the present invention has no particularity, and the general surface glaze formula can realize enamel coating. For example, in parts by weight, the components of the surface glaze are: SiO ₂ : 30%-50%, B ₂ O ₃ : 15%-25%, Al ₂ O ₃ : 5%-10%, CaO: 3%-5% %, TiO ₂ : 15% to 18%, BaO: 7% to 10%, Na ₂ O: 10% to 16%, K ₂ O: 3% to 5%, MgO: 0.5% to 0.8%, P ₂ O ₅ : 2% to 4%, ZnO: 2% to 5%.

Preferably, when the S2 glaze is sprayed, the thickness of the bottom glaze is controlled at 90-140um; the thickness of the top glaze is controlled at 80-120um.

The thickness of the porcelain layer has a great influence on the porcelain surface and the adhesion. The thickness of the bottom glaze is between 90-140um to obtain a better porcelain surface and a better adhesion level. The problem of chromatic aberration; if the thickness of the surface glaze exceeds 120um, it is easy to have insufficient surface uniformity, and the problem of chromatic aberration will also occur.

Preferably, the firing temperature of the bottom glaze is 800-840°C, and the firing time is 4 minutes; the firing temperature of the top glaze is 800-840°C, and the firing time is 4-5 minutes.

Preferably, the stainless steel substrate is austenitic stainless steel, and the content of some chemical elements in it is as follows: carbon < 0.030%, silicon < 1.00%, manganese < 2.00%, phosphorus < 0.035%, sulfur < 0.030%, nickel 8.00- 20.00%, chromium 18.00-20.00%.

Due to the many types of stainless steel, there are ferritic stainless steel, austenitic stainless steel, austenitic-ferritic duplex stainless steel, and martensitic stainless steel. The commonly used stainless steel is austenitic stainless steel, so the present invention focuses on the enamelling on austenitic stainless steel. The bottom glaze glaze provided by the present invention has the best enamel coating effect on the austenitic stainless steel with the above chemical element content.

The invention also discloses the preparation method of the above-mentioned stainless steel enamel plate, comprising the following steps:

S1 stainless steel substrate preparation: stainless steel plate is obtained after laser nitrogen cutting, corner bending, laser welding, grinding and surface treatment;

S2 glaze spraying: glaze spraying by wet spraying process;

S3 drying: drying temperature 150-200 ℃, time 10-15min;

S4 firing: the bottom glaze firing temperature is 800-840 ℃, and the firing time is 4 minutes; the surface glaze firing temperature is 800-840 ℃, and the firing time is 4-5 minutes.

The invention uses laser cutting to complete the cutting of the stainless steel plate, which can ensure the accuracy of the cutting size and facilitate the installation of the plate; and nitrogen cutting is used to protect the cutting surface from being oxidized, reduce the probability of the knife edge bursting, and the laser automatically cuts, reducing labor operation, to maximize the production capacity, the used stainless steel laser cutting process is consistent with the existing process, and the present invention will not describe it in detail. Corner bending is formed according to the existing production process. Due to the special material of stainless steel, the deformation of manual welding is large, and the process test is changed to laser welding. Since the oxidation of the laser welding seam is less, the welding seam can be slightly polished. In addition, the present invention achieves the purpose of good enamel adhesion and high quality of the enamel surface at a firing temperature of 800° C. at a low temperature.

Preferably, the thickness of the stainless steel plate during laser welding in S1 is 1.5mm, the welding power is 800W, the welding speed is 0.8m/min, and the focal length is the positive focus point.

The welding parameters of the normal production steel plate are the welding power of 2400W, the welding speed of 1m/min, and the focal length of the positive focus point. However, when welding austenitic stainless steel, the stainless steel is seriously deformed. The present invention reduces the power to reduce the amount of deformation, and then reduces the welding speed by reducing the welding speed. In order to achieve the effect of full welding seam, but the power is too low, the plate cannot be fully welded, and the laser light output is unstable. The welding effect of stainless steel plate is the best under the above parameters.

Preferably, the surface treatment in the S1 is specifically:

The first course: degreasing, sodium carbonate concentration: 8-10%, temperature: 60-70 ℃, time: 7-8min;

Second pass: degreasing, sodium carbonate concentration: 8-10%, temperature: 60-70℃, time: 7-8min;

The third course: hot water rinse, temperature: 50-60 ℃, time: 3-4min;

The fourth course: rinse with cold water, normal temperature, time: 2-3min;

The fifth step: drying, temperature: 300-350 ℃, time: 8-10min.

At present, the method to increase the adhesion of stainless steel in the industry is surface sandblasting, which forms a certain roughness on the surface of the stainless steel plate, but the sandblasting of the large plate is difficult for the site, equipment and uniformity. The invention adopts the chemical immersion method to treat the surface of the stainless steel, which has the advantages of small treatment difficulty and good effect.

Compared with the prior art, the beneficial effects of the present invention are:

1. The present invention obtains a smooth and delicate porcelain surface through the overall ratio of the above-mentioned components, using titanium dioxide and phosphorus pentoxide with good turbidity, and cooperates with CuO, CoO, NiO, MnO ₂ to promote adhesion, and then combine with In combination with other components, the bottom glaze of the stainless steel enamel plate provided by the present invention has the characteristics of high adhesion, high weather resistance and high corrosion resistance;

2. The stainless steel enamel plate prepared by using the glaze provided by the present invention at a relatively low firing temperature has good adhesion, and the obtained enamel porcelain surface is smooth and delicate;

3. Through the improvement of the preparation method, the adhesion of the stainless steel enamel plate is further improved, and the problem that the porcelain layer falls off after the collision of the low carbon steel enamel plate, the inner steel plate is not protected by the enamel layer, and the corrosion occurs.

detailed description

The technical solutions in the embodiments of the present invention will be described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Examples 1-3

A kind of bottom glaze glaze of stainless steel enamel plate, the specific component content is shown in Table 1.

Table 1: List of mass fractions (%) of each component in Examples 1-3

component	Example 1	Example 2	Example 3
SiO2	36.39	36.39	38
B 2 O 3	17.87	17.87	19
Al 2 O 3	7.06	7.06	7.06
TiO 2	1.15	1.15	1.15
BaO	2.79	2.79	2.79
Na 2 O	17.59	17.59	14.85
K 2 O	9.96	9.96	9.96
MgO	0.18	0.18	0.18
P 2 O 5	2.95	2.95	2.95
ZnO	0.57	0.57	0.57
Cr 2 O 3	0.15	0.15	0.15
CuO	0.57	0.66	0.57
CoO	0.57	0.57	0.57
NiO	1.05	1.05	1.05
MnO 2	1.15	1.06	1.15

Examples 4-6

A preparation method of bottom glaze glaze of stainless steel enamel plate, comprising the following steps:

(1) mix each component according to the proportion;

(2) Put the mixture into a high-temperature furnace and melt at 1000-1200 °C;

(3) put into water after melting and quench to form enamel frit;

(4) Turn the enamel frit into a ball mill and grind it through a 70-90 mesh sieve to form a glaze.

Examples 4-6 were prepared by using the glaze formulations of Examples 1-3 respectively.

Examples 7-9

A preparation method of a stainless steel enamel plate, comprising the following steps:

S1 stainless steel substrate preparation: 304 stainless steel plate is obtained after laser nitrogen cutting, corner bending, laser welding, grinding and surface treatment;

During laser welding, the thickness of the stainless steel plate is 1.5mm, the welding power is 800W, the welding speed is 0.8m/min, and the focal length is the positive focus point;

The surface treatment is as follows:

The first course: degreasing, concentration: 8%, temperature: 70℃, time: 8min;

Second pass: degreasing, concentration: 8%, temperature: 70℃, time: 8min;

The third course: hot water rinse, temperature: 50-60 ℃, time: 3min;

The fourth course: rinse with cold water, normal temperature, time: 2min;

The fifth step: drying, temperature: 300℃, time: 8min;

S2 glaze spraying: use the base glaze glaze of Example 4 to carry out glaze spraying by wet spraying process; the base glaze thickness is controlled at 90-140um; the top glaze thickness is controlled at 80-120um;

S3 drying: drying temperature 160 ℃, time 12min;

S4 firing: the bottom glaze is fired for 4 minutes; the top glaze is fired at 820°C and fired for 4 minutes.

Examples 7-9 all adopt the above-mentioned preparation method, the difference is that the firing temperature of the bottom glaze is 800°C, 820°C and 840°C, respectively.

Examples 10-12

The base glaze in Example 7-9 was changed to the base glaze glaze prepared in Example 5, and the rest was the same as that of Example 7-9.

Comparative Examples 13-15

The bottom glaze in Example 4-6 was changed to the bottom glaze glaze prepared in Example 6 and fired, and the rest were the same as those in Example 7-9.

The stainless steel enamel plates made in Examples 7-15 were tested for adhesion with an adhesion tester respectively. The adhesion test results and the quality of the porcelain surface are recorded in Table 2.

Table 2: Various test results of the stainless steel enamel plates made in Examples 4-12

project	Firing process	Adhesion level	Porcelain surface quality
Example 7	800℃; 4.0min	Level 1	smooth and delicate
Example 8	820℃; 4.0min	Level 1	smooth and delicate
Example 9	840℃; 4.0min	Level 1	smooth and delicate
Example 10	800℃; 4.0min	Level 3	smooth and delicate
Example 11	820℃; 4.0min	Level 3	smooth and delicate
Example 12	840℃; 4.0min	Level 1	Porcelain surface is boiling and has pinholes
Example 13	800℃; 4.0min	Level 3	smooth and delicate
Example 14	820℃; 4.0min	Level 1	smooth and delicate
Example 15	840℃; 4.0min	Level 1	Porcelain surface is boiling and has pinholes

In combination with Table 1 and Table 2, it can be known that the stainless steel enamel glaze is obtained according to the components and mass fractions of Example 1 to Example 3. After firing at different temperatures, the porcelain surfaces fired by the glaze formula of Example 1 are all smooth and delicate. , the lowest temperature required to form a level 1 bond. Therefore, the base glaze glaze formula of Example 1 is the best formula, and the obtained stainless steel enamel glaze has good porcelain surface quality while ensuring good adhesion.

Examples 16-17

The spraying thickness of the bottom glaze was modified to 90-120um and 120-140um respectively, and the rest were the same as those in Example 7.

Comparative Examples 1-4

The spraying thickness of the bottom glaze was modified to 30-50um, 50-70um, 70-90um, and 140-160um respectively, and the rest were the same as those in Example 7.

The stainless steel enamel plates prepared in Examples 16-17 and Comparative Examples 1-4 were tested for adhesion with an adhesion tester, respectively. The adhesion test results and the quality of the porcelain surface are recorded in Table 3.

Table 3: Various test results of stainless steel enamel plates made in Examples 4, 13 and Comparative Examples 1-4

It can be seen from Table 3 that the thickness of the underglaze porcelain layer has a great influence on the porcelain surface and the adhesion. The porcelain layer thickness between 90-140um can obtain better porcelain surface and better adhesion.

Research on Different Welding Processes

The 304 stainless steel plate was welded by laser welding, and the welding power and welding speed were changed. The welding effect is shown in Table 4.

Table 4: Stainless steel welding process test record table: using laser welding process.

It can be seen from Table 4 that the welding effect of the stainless steel plate is the best under the welding parameters defined by the present invention.

The technical solutions provided by the present invention have been described in detail above, and specific examples are used to illustrate the principles and implementations of the present invention. The descriptions of the above embodiments are only used to help understand the methods and core ideas of the present invention; At the same time, for those skilled in the art, according to the idea of the present invention, there will be changes in the specific embodiments and application scope. To sum up, the content of this specification should not be construed as a limitation of the present invention.

Claims (10)

1. A bottom glaze glaze for a stainless steel enamel plate is characterized in that, by mass percentage, it comprises the following components:

   _SiO2 30-38%; B2O3 15-19%; _Al2O3 6-10% _{; TiO2 1-2} % _; BaO 1-4%; Na2O 14-19% _{; K2O5} -10%; MgO 0.1-0.6%; _{P2O5 2-4} %; ZnO 0.2-0.8%; _Cr2O3 0.1-0.3%; _CuO 0.4-0.8%; CoO 0.3-0.9%; NiO 0.7-1.2 % and MnO ₂ 0.8-1.3%.
2. The bottom glaze glaze of a kind of stainless steel enamel plate according to claim 1, is characterized in that, by mass percentage, comprises the following components:

   SiO ₂ 36.39%; B ₂ O ₃ 17.87%; Al ₂ O ₃ 7.06%; TiO ₂ 1.15%; BaO 2.79%; Na ₂ O 17.59%; K ₂ O 9.96%; MgO 0.18%; P ₂ O ₅ 2.95% ; ZnO 0.57%; _Cr2O3 0.15%; _CuO 0.57%; CoO 0.57%; NiO 1.05% and _MnO2 1.15%.
3. The preparation method of the bottom glaze glaze of a kind of stainless steel enamel plate according to claim 1 and 2, is characterized in that, comprises the following steps:

   (1) mix each component according to the proportion;

   (2) put the mixture into the high temperature furnace to melt;

   (3) put into water after melting and quench to form enamel frit;

   (4) The enamel frit is turned into a ball mill and ground to form a glaze.
4. A stainless steel enamel plate, characterized in that it comprises: a stainless steel substrate, a bottom glaze and a top glaze;

   Wherein, the bottom glaze and the top glaze are sequentially attached on the stainless steel substrate; and the raw material of the bottom glaze is the bottom glaze glaze according to any one of claims 1-2.
5. The stainless steel enamel plate according to claim 4, wherein the thickness of the bottom glaze is 90-140um; the thickness of the surface glaze is 80-120um.
6. The stainless steel enamel plate according to claim 4, wherein the firing temperature of the bottom glaze is 800-840°C, and the firing time is 4 minutes; the firing temperature of the top glaze is 800-840°C, and the firing time is 4 minutes. -5min.
7. The stainless steel enamel plate according to claim 4, wherein the stainless steel substrate is austenitic stainless steel, and the content of some chemical elements is as follows: carbon < 0.030%, silicon < 1.00%, manganese < 2.00% , Phosphorus <0.035%, Sulfur <0.030%, Nickel 8.00-20.00%, Chromium 18.00-20.00%.
8. A kind of preparation method of stainless steel enamel plate according to claim 4-7, is characterized in that, comprises the following steps:

   S1 stainless steel substrate preparation: stainless steel plate is obtained after laser nitrogen cutting, corner bending, laser welding, grinding and surface treatment;

   S2 glaze spraying: glaze spraying by wet spraying process;

   S3 drying: drying temperature 150-200 ℃, time 10-15min;

   S4 firing: the bottom glaze firing temperature is 800-840 ℃, and the firing time is 4 minutes; the surface glaze firing temperature is 800-840 ℃, and the firing time is 4-5 minutes.
9. The method for preparing a stainless steel enamel plate according to claim 8, wherein the thickness of the stainless steel plate during laser welding described in S1 is 1.5mm, the welding power is 800W, the welding speed is 0.8m/min, and the focal length is Aiming at the focal point.
10. The preparation method of a kind of stainless steel enamel plate according to claim 8, is characterized in that, the surface treatment in described S1 is specifically:

    The first course: degreasing, sodium carbonate concentration: 8-10%, temperature: 60-70 ℃, time: 7-8min;

    Second pass: degreasing, sodium carbonate concentration: 8-10%, temperature: 60-70℃, time: 7-8min;

    The third course: hot water rinse, temperature: 50-60 ℃, time: 3-4min;

    The fourth course: rinse with cold water, normal temperature, time: 2-3min;

    The fifth step: drying, temperature: 300-350 ℃, time: 8-10min.