阅读说明：本技术 一种热态修补用铝硅质耐磨喷涂料的制备方法 (Preparation method of aluminum-silicon wear-resistant spray coating for thermal state repair ) 是由 陈金凤 程水明 丛培源 项冰 于 2021-08-16 设计创作，主要内容包括：本发明公开了一种热态修补用铝硅质耐磨喷涂料的制备方法,将废电瓷颗粒和硅灰按质量比100︰(20～25)加入行星式混练机中混合5～8分钟,得到混合颗粒料；将所得混合颗粒料、ρ-氧化铝、黏土、硅线石和硅藻土加入回转式混练机中混合10～12分钟,得到前驱体混合料；向所得前驱体混合料中依次加入占所述前驱体混合料6～8wt％的温石棉纤维和8～10wt％的磷酸二氢铝溶液,搅拌5～8分钟,密封困料30～40分钟,得到混合料；向所得混合料中加入占所述混合料0.5～1.5wt％的羧甲基纤维素,搅拌5～8分钟,即得热态修补用铝硅质耐磨喷涂料；所得耐磨喷涂料结合性强,与衬体烧结整体性好,施工回弹少,耐磨性强,制备过程工艺简单,且以工业固废为原料,大幅降低了喷涂料的开发成本,环境友好。(The invention discloses a preparation method of an aluminum-silicon wear-resistant spray coating for hot repair, which comprises the steps of adding waste electric ceramic particles and silica fume into a planetary type mixing machine according to the mass ratio of 100: 20-25, and mixing for 5-8 minutes to obtain a mixed particle material; adding the obtained mixed granular material, rho-alumina, clay, sillimanite and diatomite into a rotary mixing machine to mix for 10-12 minutes to obtain a precursor mixture; sequentially adding chrysotile fibers accounting for 6-8 wt% of the precursor mixture and aluminum dihydrogen phosphate solution accounting for 8-10 wt% of the precursor mixture into the precursor mixture, stirring for 5-8 minutes, and sealing for ageing for 30-40 minutes to obtain a mixture; adding carboxymethyl cellulose accounting for 0.5-1.5 wt% of the mixture into the obtained mixture, and stirring for 5-8 minutes to obtain the aluminum-silicon wear-resistant spray coating for thermal state repair; the obtained wear-resistant spray coating has the advantages of strong associativity, good sintering integrity with a lining body, less construction resilience, strong wear resistance and simple preparation process, takes industrial solid wastes as raw materials, greatly reduces the development cost of the spray coating, and is environment-friendly.)

1. A preparation method of an aluminum-silicon wear-resistant spray coating for hot repair is characterized by comprising the following steps:

1) adding waste electric porcelain particles and silica fume into a planetary type mixing machine according to the mass ratio of 100: 20-25, and mixing for 5-8 minutes to obtain a mixed particle material;

2) adding the obtained mixed granular material, rho-alumina, clay, sillimanite and diatomite into a rotary mixing machine according to the mass ratio of 100: 5-8: 10-15: 15-20, and mixing for 10-12 minutes to obtain a precursor mixture;

3) sequentially adding chrysotile fibers accounting for 6-8 wt% of the precursor mixture and aluminum dihydrogen phosphate solution accounting for 8-10 wt% of the precursor mixture into the precursor mixture, stirring for 5-8 minutes, and sealing for ageing for 30-40 minutes to obtain a mixture;

4) adding carboxymethyl cellulose accounting for 0.5-1.5 wt% of the mixture into the obtained mixture, and stirring for 5-8 minutes to obtain the aluminum-silicon wear-resistant spray coating for thermal state repair.

2. The method for preparing the aluminum-silicon wear-resistant spray coating for hot patching as claimed in claim 1, wherein the particle size of the waste electroceramic particles is 0.1-2 mm, and the bulk density of the waste electroceramic particles is 2.68-2.84 g/cm³8-10% of water absorption, Al₂O₃40 to 45 wt% of SiO₂The content is 45-50 wt%.

3. The method for preparing the aluminum-silicon wear-resistant spray coating for hot patching as claimed in claim 1, wherein the particle size of the rho-alumina is 80-100 μm, and Al is₂O₃The content is more than or equal to 98.5 wt%, and the true density is 3.4-3.6 g/cm³。

4. The method for preparing the aluminum-silicon wear-resistant spray coating for thermal repair according to claim 1, wherein the clay has a particle size of 50 to 60 μm and Al₂O₃25 to 30 wt% of SiO₂The content is 30-40 wt%, and the true density is 1.4-1.6 g/cm³。

5. The method for preparing the aluminum-silicon wear-resistant spray coating for hot patching as claimed in claim 1, wherein the sillimanite has a particle size of 40-50 μm and Al₂O₃60 to 65 wt% of SiO₂The content is 30-35 wt%, and the true density is 3.0-3.1 g/cm³。

6. The method for preparing the aluminum-silicon wear-resistant spray coating for thermal repair according to claim 1, wherein the diatomite has a particle size of 60-100 μm and Al₂O₃3-5 wt% of SiO₂The content is 85-88 wt%, and the true density is 0.6-0.8 g/cm³。

7. The method for preparing the aluminum-silicon wear-resistant spray coating for hot patching as claimed in claim 1, wherein the SiO of the chrysotile fiber₂35-40 wt% of MgO, 40-45 wt% of Al₂O₃0.5 to 2 wt% of Fe₂O₃The content is less than or equal to 0.8 wt%, the diameter of the chrysotile fiber is 5-15 mu m, the length of the chrysotile fiber is 5-25 mm, and the volume weight of the chrysotile fiber is 0.4-0.6 g/cm³。

Technical Field

The invention belongs to the technical field of coatings, and particularly relates to a preparation method of an aluminum-silicon wear-resistant spray coating for thermal state repair

Background

The spray coating is an unshaped refractory material which is constructed by taking high-speed airflow as a carrier, is mainly suitable for quickly repairing the lining of a kiln, does not need to erect a template in the construction process, and has the characteristics of time saving, labor saving and quick construction.

The spray coating can be classified into dry spraying, semi-wet spraying, mixed spraying and the like, but generally, the spray coating is required to have good bonding property, adhesiveness and sintering property (weibo. "influence of binder variety on spray repair material performance", refractory and lime ", 2019, 44 (6): pp 35-37).

The binding property of the spray paint mainly derives from the performance of a binding agent, and the currently commonly used binding agent comprises water system binding (Zhang Qingxia, Nie Jianhua, Lihong wave, and the like) which mainly comprises cement, water glass or sol and the like₂Influence of fine powder on performance of cement-bonded aluminum-magnesium gunning material "[ refractory ], 2020, 54 (5): pp 390-394), the binding agents have the following disadvantages: (1) the water-system-combined spray paint inevitably contains a large amount of water, which is beneficial to construction, but finally escapes at high temperature to leave air holes in the material, so that the material is cracked; (2) the high temperature performance of water-based bonded spray coatings is degraded by the impurity components in the binder. For example, the cement contains calcium, the water glass contains sodium and the like, and the components are easy to form low-melting-point phases at high temperature, so that the high-temperature performance of the spray paint is seriously influenced.

The adhesion of the spray paint is mainly due to the interaction of the grain composition of the components with the binder. Too high or too low adhesion is not good for spray coating (Rong. "development of plastic gunning method and gunning material", fire-resistant and lime, 2011, 36 (1): pp 26-29). The adhesion is too high, and the spray paint is easy to agglomerate and difficult to spread; too low adhesiveness leads to more rebound of the spray paint, waste of raw materials and influence on construction.

The sintering performance of the spray paint is mainly embodied in two aspects, namely the spray paint is rapidly sintered, and on the other hand, the spray paint can be sintered with a body material of a kiln lining body to form an effective whole (Weibo. "influence of a magnesium oxide raw material on the sintering performance of an electric furnace gunning material", refractoriness and lime ", 2017, 42 (4): pp 30-33). Therefore, the sintering performance of the gunning material itself cannot be measured, and the gunning material and the lining body are considered to form sintering and be tightly combined under the service environment.

CN201910783154.5 discloses a thermal state repairing spray coating and a preparation method thereof, which is prepared by taking brown corundum, Guangxi mud and pure calcium aluminate cement as main raw materials and adding water for mixing; although the problem of rapid hot repair is solved, the spray paint has good bonding and high strength; however, the cement in combination with the calcium-containing component deteriorates the high temperature thermal state properties of the spray paint.

CN201310366807.2 discloses a gunning mix for kiln repair, which is prepared by taking magnesite, forsterite and the like as main raw materials and borax as a bonding agent, adding water and mixing uniformly; although the adhesion rate of the gunning material is improved, the anti-stripping performance is good; however, magnesite and other raw materials are high in cost and easy to hydrate, and the hardening and sintering of the materials are affected.

CN201610010144.4 discloses an andalusite corundum anti-falling gunning mix, which takes andalusite corundum as a raw material and is tightly combined by embedding and wrapping andalusite and corundum; although the refractory degree, the thermal shock resistance and the falling prevention of the gunning material are improved; however, the mismatch of the thermal expansion coefficients of the raw material components at high temperature easily causes microcracks and pores in the material.

Disclosure of Invention

The invention mainly aims to provide a preparation method of an aluminum-silicon wear-resistant spray coating for thermal state repair, which has the advantages of strong binding property, good sintering integrity with a lining body, less construction resilience, strong wear resistance, simple preparation process, great reduction of development cost of the spray coating by taking industrial solid wastes as raw materials, and environmental friendliness.

In order to achieve the purpose, the technical scheme is as follows:

a preparation method of an aluminum-silicon wear-resistant spray coating for hot repair comprises the following steps:

1) adding waste electric porcelain particles and silica fume into a planetary type mixing machine according to the mass ratio of 100: 20-25, and mixing for 5-8 minutes to obtain a mixed particle material;

2) adding the obtained mixed granular material, rho-alumina, clay, sillimanite and diatomite into a rotary mixing machine according to the mass ratio of 100: 5-8: 10-15: 15-20, and mixing for 10-12 minutes to obtain a precursor mixture;

3) sequentially adding chrysotile fibers accounting for 6-8 wt% of the precursor mixture and aluminum dihydrogen phosphate solution accounting for 8-10 wt% of the precursor mixture into the precursor mixture, stirring for 5-8 minutes, and sealing for ageing for 30-40 minutes to obtain a mixture;

4) adding carboxymethyl cellulose accounting for 0.5-1.5 wt% of the mixture into the obtained mixture, and stirring for 5-8 minutes to obtain the aluminum-silicon wear-resistant spray coating for thermal state repair.

According to the scheme, the granularity of the waste electric porcelain particles is 0.1-2 mm, and the volume density of the waste electric porcelain particles is 2.68-2.84 g/cm³8-10% of water absorption, Al₂O₃40 to 45 wt% of SiO₂The content is 45-50 wt%.

According to the scheme, the granularity of the rho-alumina is 80-100 mu m, and Al₂O₃The content is more than or equal to 98.5 wt%, and the true density is 3.4-3.6 g/cm³。

According to the scheme, the clay has the granularity of 50-60 mu m and Al₂O₃25 to 30 wt% of SiO₂The content is 30-40 wt%, and the true density is 1.4-1.6 g/cm³。

According to the scheme, the sillimanite has the granularity of 40-50 mu m and Al₂O₃60 to 65 wt% of SiO₂The content is 30-35 wt%, and the true density is 3.0-3.1 g/cm³。

According to the scheme, the particle size of the diatomite is 60-100 mu m, and Al is₂O₃3-5 wt% of SiO₂The content is 85-88 wt%, and the true density is 0.6-0.8 g/cm³。

According to the scheme, the SiO of the chrysotile fiber₂35-40 wt% of MgO, 40-45 wt% of Al₂O₃0.5 to 2 wt% of Fe₂O₃The content is less than or equal to 0.8 wt%, the diameter of the chrysotile fiber is 5-15 mu m, the length of the chrysotile fiber is 5-25 mm, and the volume weight of the chrysotile fiber is 0.4-0.6 g/cm³。

Compared with the prior art, the invention has the following beneficial effects:

the invention takes the industrial solid wastes such as waste electroceramics, silica fume and the like as raw materials, and reduces the preparation cost of the spray coating. The preparation process needs no special equipment or instrument and is simple.

The invention utilizes the oxidation of simple substance Si in the silica fume at high temperature and thermal state to form active SiO₂The components improve the filling and sintering performance and promote the rapid sintering and integral forming of the spray coating.

The invention adopts cement-free combination, avoids the introduction of harmful components containing calcium and the like, and ensures the high-temperature thermal-state mechanical property of the spray coating.

The invention selects phosphate combination, and no harmful gas or liquid is generated in the preparation and service processes; the phosphate and the carboxymethyl cellulose are combined in a crosslinking manner, so that the binding performance of the spray coating is obviously improved, and the resilience of the spray coating is reduced.

According to the invention, a columnar mullite network staggered structure is formed through high-temperature secondary mullite reaction of sillimanite, so that the wear resistance of the spray coating is enhanced; simultaneously utilizes the volume expansion caused by the secondary mullite reaction to offset SiO₂The volume shrinkage caused by the crystal transformation keeps the good volume stability of the spray paint.

According to the invention, the heat-conducting property of the spray coating is reduced by utilizing the accumulation and filling of the diatomite and the chrysotile fiber, so that the energy conservation and consumption reduction of the high-temperature industrial kiln are realized.

The main raw materials used in the invention are low in cost and easy to obtain, so that the resource utilization of industrial solid wastes is realized, and the environmental protection effect is obvious; the prepared wear-resistant spray coating has strong associativity, good sintering integrity with a lining body, less construction resilience and strong wear resistance, and can be applied to spray repair of a material returning device of a circulating fluidized bed boiler.

The aluminum-silicon wear-resistant spray coating for hot repair prepared by the invention is detected as follows: the resilience rate is 2.7-3.5%; the volume density of the sintered product at 1250 ℃ and 131 is 2.43-2.68 g/cm³；1250℃1The abrasion loss of the normal-temperature abrasion resistance test after 31 burning is 2.4-3.3 cm³。

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The invention relates to a preparation method of an aluminum-silicon wear-resistant spray coating for hot repair, which comprises the following specific steps:

1) adding waste electric porcelain particles and silica fume into a planetary type mixing machine according to the mass ratio of 100: 20-25, and mixing for 5-8 minutes to obtain a mixed particle material;

2) adding the obtained mixed granular material, rho-alumina, clay, sillimanite and diatomite into a rotary mixing machine according to the mass ratio of 100: 5-8: 10-15: 15-20, and mixing for 10-12 minutes to obtain a precursor mixture;

3) sequentially adding chrysotile fibers accounting for 6-8 wt% of the precursor mixture and aluminum dihydrogen phosphate solution accounting for 8-10 wt% of the precursor mixture into the precursor mixture, stirring for 5-8 minutes, and sealing for ageing for 30-40 minutes to obtain a mixture;

4) adding carboxymethyl cellulose accounting for 0.5-1.5 wt% of the mixture into the obtained mixture, and stirring for 5-8 minutes to obtain the aluminum-silicon wear-resistant spray coating for thermal state repair.

In order to avoid repetition, the materials related to the specific embodiment are uniformly described as follows, and are not described in the embodiment again:

the particle size of the waste electric porcelain particles is 0.1-2 mm, and the volume density of the waste electric porcelain particles is 2.68-2.84 g/cm³8-10% of water absorption, Al₂O₃40 to 45 wt% of SiO₂The content is 45-50 wt%.

The particle size of the rho-alumina is 80-100 mu m, and Al₂O₃The content is more than or equal to 98.5 wt%, and the true density is 3.4-3.6 g/cm³。

The clay has a particle size of 50-60 mu m and Al₂O₃In an amount of25～30wt％，SiO₂The content is 30-40 wt%, and the true density is 1.4-1.6 g/cm³。

The sillimanite has a particle size of 40-50 μm and Al₂O₃60 to 65 wt% of SiO₂The content is 30-35 wt%, and the true density is 3.0-3.1 g/cm³。

The particle size of the diatomite is 60-100 mu m, and Al₂O₃3-5 wt% of SiO₂The content is 85-88 wt%, and the true density is 0.6-0.8 g/cm³。

SiO of the chrysotile fiber₂35-40 wt% of MgO, 40-45 wt% of Al₂O₃0.5 to 2 wt% of Fe₂O₃The content is less than or equal to 0.8 wt%, the diameter of the chrysotile fiber is 5-15 mu m, the length of the chrysotile fiber is 5-25 mm, and the volume weight of the chrysotile fiber is 0.4-0.6 g/cm³。

Example 1

1) Adding the waste electric porcelain particles and the silica fume into a planetary type mixing machine according to the mass ratio of 100: 23, and mixing for 6 minutes to obtain mixed particles;

2) adding the mixed granular material, rho-alumina, clay, sillimanite and diatomite into a rotary mixing machine for mixing for 10 minutes according to the mass ratio of 100: 5: 12: 13: 18 to obtain a precursor mixture;

3) sequentially adding chrysotile fibers accounting for 6 wt% of the precursor mixture and aluminum dihydrogen phosphate solution accounting for 8 wt% of the precursor mixture into the precursor mixture, stirring for 7 minutes, and sealing for ageing for 35 minutes to obtain a mixture;

4) adding carboxymethyl cellulose accounting for 0.8 wt% of the mixture into the mixture, and stirring for 7 minutes to obtain the aluminum-silicon wear-resistant spray coating for thermal state repair.

The aluminum-silicon wear-resistant spray coating for hot repair prepared in the embodiment is detected as follows: the rebound resilience is 2.8 percent; the volume density of the sintered body is 2.52g/cm at 1250℃ and 131³(ii) a The abrasion loss of the normal temperature abrasion resistance test after the roasting of 1250 ℃ at 131 ℃ is 2.7m³。

Example 2

1) Adding the waste electric porcelain particles and the silica fume into a planetary type mixing machine according to the mass ratio of 100: 22, and mixing for 5 minutes to obtain a mixed particle material;

2) adding the mixed granular material, rho-alumina, clay, sillimanite and diatomite into a rotary type mixing machine for mixing for 12 minutes according to the mass ratio of 100: 8: 14: 13: 17 to obtain a precursor mixture;

3) sequentially adding chrysotile fibers accounting for 7.5 wt% of the precursor mixture and aluminum dihydrogen phosphate solution accounting for 8.5 wt% of the precursor mixture into the precursor mixture, stirring for 7 minutes, and sealing for ageing for 30 minutes to obtain a mixture;

4) adding carboxymethyl cellulose accounting for 1.2 wt% of the mixture into the mixture, and stirring for 5 minutes to obtain the aluminum-silicon wear-resistant spray coating for thermal state repair.

The aluminum-silicon wear-resistant spray coating for hot repair prepared in the embodiment is detected as follows: the rebound resilience is 3.3%; the volume density of the sintered body is 2.66g/cm at 1250℃ and 131³(ii) a The abrasion loss of the normal temperature abrasion resistance test after the roasting of 1250 ℃ at 131 ℃ is 2.4cm³。

Example 3

1) Adding the waste electric porcelain particles and the silica fume into a planetary type mixing machine according to the mass ratio of 100: 25, and mixing for 6 minutes to obtain mixed particles;

2) adding the mixed granular material, rho-alumina, clay, sillimanite and diatomite into a rotary mixing machine for mixing for 11 minutes according to the mass ratio of 100: 6: 11: 13: 18 to obtain a precursor mixture;

3) sequentially adding chrysotile fibers accounting for 7 wt% of the precursor mixture and aluminum dihydrogen phosphate solution accounting for 9.5 wt% of the precursor mixture into the precursor mixture, stirring for 8 minutes, and sealing for ageing for 40 minutes to obtain a mixture;

4) adding carboxymethyl cellulose accounting for 1.5 wt% of the mixture into the mixture, and stirring for 7 minutes to obtain the aluminum-silicon wear-resistant spray coating for thermal state repair.

The aluminum-silicon wear-resistant spray coating for hot repair prepared in the embodiment is detected as follows: the rebound resilience is 3.1%; the volume density of the sintered body is 2.61g/cm at 1250℃ and 131³(ii) a The abrasion loss of the normal temperature abrasion resistance test after the roasting of 1250 ℃ at 131 ℃ is 2.8cm³。

Example 4

1) Adding the waste electric porcelain particles and the silica fume into a planetary type mixing machine according to the mass ratio of 100: 24, and mixing for 7 minutes to obtain mixed particles;

2) adding the mixed granular material, rho-alumina, clay, sillimanite and diatomite into a rotary type mixing machine for mixing for 12 minutes according to the mass ratio of 100: 8: 15: 12: 15 to obtain a precursor mixture;

3) sequentially adding chrysotile fibers accounting for 6 wt% of the precursor mixture and aluminum dihydrogen phosphate solution accounting for 10 wt% of the precursor mixture into the precursor mixture, stirring for 5 minutes, and sealing for ageing for 30 minutes to obtain a mixture;

4) adding carboxymethyl cellulose accounting for 0.6 wt% of the mixture into the mixture, and stirring for 8 minutes to obtain the aluminum-silicon wear-resistant spray coating for thermal state repair.

The aluminum-silicon wear-resistant spray coating for hot repair prepared in the embodiment is detected as follows: the rebound resilience is 2.9 percent; the volume density of the sintered body is 2.52g/cm at 1250℃ and 131³(ii) a The abrasion loss of the normal temperature abrasion resistance test after the roasting of 1250 ℃ at 131 ℃ is 3.3cm³。

It should be noted that the above-mentioned embodiments are only preferred embodiments of the present invention, and the present invention is not limited thereto, and although the present invention has been described in detail with reference to the embodiments, it will be apparent to those skilled in the art that modifications can be made to the technical solutions described in the above-mentioned embodiments, or equivalent substitutions of some technical features, but any modifications, equivalents, improvements and the like within the spirit and principle of the present invention shall be included in the protection scope of the present invention.