A hydrolytic ceramic ball inner core, a ceramic ball and a preparation method of the ceramic ball

Abstract

The application discloses a hydrolytic ceramic ball inner core, which comprises the following components in percentage by mass: Al2O3: 5-20%, SiO2: 0.5-3%, ZrO2: 1-10%, MgO: 5-40%, CaO: 15-50%, BaO: 10-50%, SrO: 0.5-40%, Y2O3: 0.1-1%, and CeO2: 0.2-3%. The application further discloses a ceramic ball containing the hydrolytic ceramic ball inner core. The application further discloses a ceramic ball containing the hydrolytic ceramic ball inner core and a preparation method of the ceramic ball. In the application, a certain amount of glass phase and ceramic framework are formed during sintering of the inner core, the ceramic has a certain ceramic strength, and the strength of the whole target ceramic ball can be ensured from being affected by the inner core too much. Meanwhile, the excess alkali earth metal oxides generated during the sintering process are preserved, the ceramic ball is gradually abraded and becomes smaller during use, when the inner core is reached, the alkali earth metal oxides on the inner core will produce a hydrolysis reaction when meeting water, and the inner core will be gradually consumed.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of ceramic balls, in particular to a ceramic ball core that can be hydrolyzed, a ceramic ball and a preparation method of the ceramic ball. BACKGROUND

[0002] With the increasing scarcity of mineral resources and the implementation of the concept of sustainable development of environmental protection and low carbon, the demand for extraction and refining of mineral resources is increasingly urgent, thereby further promoting the development of mills and fine grinding technology, and wear-resistant ceramic balls as the food of mills are increasingly concerned. As a consumable product, the wear resistance and grinding efficiency of wear-resistant ceramic balls are the focus of customers, but we also find that small grinding balls are inevitably produced during the use of grinding balls, and the kinetic energy contained in the small grinding balls is relatively small, which cannot provide good grinding effect when grinding coarse powder, and instead occupies a certain grinding ball loading volume to affect the grinding efficiency. At this time, if the grinding balls are taken out for screening, and then the grinding balls meeting the particle size are put back into the machine, the continuity of production will be hindered, and a large amount of manpower and material resources will be consumed, and at the same time, the small grinding balls screened out cannot be well recycled, and the waste solid pollution is increased. Therefore, how to quickly grind or degrade the small balls is the pain point of the customer demand of grinding balls.

[0003] Patent CN109516774B discloses a preparation method of artificial spherical ceramic composite sand, the structure of the ceramic composite sand is mainly a double-layer structure of "core + outer layer", the core adopts a relatively coarse particle size of main powder, which is one or more than two of low-grade bauxite, low-grade corundum, nickel tailings slag and fly ash; the outer layer adopts a relatively fine particle size of main powder, which is one or more than two of high-grade corundum, high-grade bauxite and corundum powder; the rolling granulation method is used for granulation, and the obtained product is sintered in a rotary kiln, but the purpose of the patent is to reduce the cost by adopting the structure of core plus outer layer, and the problems of small grinding balls affecting the grinding efficiency, the transition layer between the core and the outer layer and the sintering shrinkage consistency are not solved. SUMMARY

[0004] The purpose of the present application is to provide a ceramic ball core that can be hydrolyzed.

[0005] The present application also discloses a ceramic ball containing a ceramic ball core that can be hydrolyzed.

[0006] The present application also discloses a preparation method of a ceramic ball containing a ceramic ball core that can be hydrolyzed.

[0007] The innovation of the present application is that a certain amount of glass phase and ceramic framework are formed during sintering of the core, which has a certain ceramic strength and can ensure that the strength of the whole target ceramic ball is not affected by the core being too large; meanwhile, the excess alkali earth metal oxides generated during the sintering process are preserved, and the ceramic ball is gradually worn and becomes smaller during use, and when the core is reached, the alkali earth metal oxides on the core will hydrolyze when meeting water, and gradually expand, so that the core is rapidly consumed.

[0008] To achieve the above-mentioned application purposes, the technical scheme of the present application is:

[0009] A ceramic ball core that can hydrolyze, comprising the following raw materials in mass percentage: Al2O3: 5-20%, SiO2: 0.5-3%, ZrO2: 1-10%, MgO: 5-40%, CaO: 15-50%, BaO: 10-50%, SrO: 0.5-40%, Y2O3: 0.1-1%, and CeO2: 0.2-3%.

[0010] A ceramic ball containing a ceramic ball core that can hydrolyze, the ceramic ball comprising, from inside to outside, a core, a transition layer, and an outer layer; the transition layer is an inert layer. Directly covering the ceramic matrix material outside the alkali earth metal oxide layer, a serious mutual erosion phenomenon occurs during the sintering process, forming a large amount of glass phase. The present application uses a transition layer, which is mainly used to avoid the contact between the core alkali earth metal compound and the outer layer ceramic matrix material during the sintering process to form a large amount of glass phase, thereby preventing excessive consumption of the alkali earth metal oxide and the outer layer ceramic matrix material; in addition, the presence of the transition layer also plays a role in adjusting the shrinkage rate, avoiding the cracking caused by the large difference in shrinkage rate between the inner and outer layers.

[0011] A method for preparing a ceramic ball containing a ceramic ball core that can hydrolyze, comprising the following steps:

[0012] (1) batching: taking core raw materials, transition layer raw materials, and outer layer raw materials;

[0013] (2) powder preparation: the core raw materials, transition layer raw materials, and outer layer raw materials are respectively subjected to coarse grinding-fine grinding-spray drying to obtain core powder, transition layer powder, and outer layer powder, wherein the fineness of the core powder is 5-20 microns, the fineness of the transition layer powder is 2-10 microns, and the fineness of the outer layer powder is 1-5 microns;

[0014] (3) Forming: using rolling forming method, spraying forming slurry while feeding, the ball blank slowly rolls up; first, using core powder rolling forming to 10~30% of the target ceramic ball size, obtaining the core; then, changing to transition layer powder, coating forming to 11~40% of the target ceramic ball size, obtaining the core coated with transition layer; finally, changing to outer layer powder, coating forming to the target size, obtaining the target ceramic ball blank body containing core, transition layer and outer layer;

[0015] (4) Sintering: the sintering temperature of the target ceramic ball blank body is room temperature~350℃, the heating rate is 2℃ / min; 350~800℃, the heating rate is 1℃ / min; 800~1250℃, the heating rate is 8℃ / min; 1250~the highest temperature, the heating rate is 1℃ / min; keeping the highest temperature for 5h, then 8℃ / min cooling to room temperature; obtaining the ceramic ball containing core.

[0016] Further, the transition layer raw material is one of Al2O3 and ZrO2 or a combination of the two.

[0017] Further, the highest temperature is 1250~1400℃, and the outer layer raw material is ceramic powder with a sintering temperature of 1250~1400℃.

[0018] Further, the forming slurry is divided into core forming slurry, transition layer forming slurry and outer layer forming slurry, the core forming slurry contains 0.2~0.8% Dow Acusol 420N, 0.1~1% PVA2488 and 0.1~0.5% Rohm & Haas ACUMER 9300; the transition layer forming slurry contains 0.1~1% Dow Duramax B-1000 and 0.1~1% PVA2488; the outer layer forming slurry contains 0.1~1% PVA2488, 0.05~0.5% sodium hexametaphosphate and 0.05~0.2% white sugar. Ceramic powder needs to use forming slurry when forming, and the conventional forming slurry is composed of water and a certain amount of binder, dispersant and plasticizer, etc., and the fineness, surface charge, surface morphology and hydrophilic performance of each powder are different, which also leads to different rolling forming performance of different powders, and different forming slurry is needed to adjust the forming performance; especially in the multi-layer ceramic rolling forming method, the problem of difficult combination between layers of ceramic raw materials is often encountered. For these problems, the forming slurry is optimized.

[0019] The beneficial effects of the present application are:

[0020] The ceramic ball core prepared by the method of compounding the alkaline earth metal compound with the ceramic matrix material in the application has a certain amount of glass phase and ceramic framework formed during sintering, has a certain ceramic strength, and can ensure that the strength of the whole target ceramic ball is not affected by the too large inner core; meanwhile, the excess alkaline earth metal oxide generated during the sintering process is preserved, the ceramic ball is gradually worn and becomes smaller during use, when the inner core is reached, the alkaline earth metal oxide on the inner core will hydrolyze and gradually swell when meeting water, so that the inner core is rapidly consumed.

[0021] The transition layer is used in the application to avoid the contact between the inner core alkaline earth metal compound and the outer layer ceramic matrix material during sintering to form a large amount of glass phase, and to further prevent the excessive consumption of the alkaline earth metal oxide and the outer layer ceramic matrix material; in addition, the existence of the transition layer also plays a role in adjusting the shrinkage rate to avoid the cracking caused by the too large difference between the shrinkage rates of the inner and outer layers.

[0022] The application can quickly eliminate the inner core which is ground but has little grinding effect, vacates space for the mill to add new grinding balls, reduces the influence of the low grinding efficiency of the mill caused by too many small balls in the ceramic ball inner core, and simultaneously, the characteristics of the rapid and automatic swelling and consumption of the inner core avoid the processes of shutdown, disassembly, ball screening and the like, improve the production capacity and economic benefits; in addition, the characteristics of the rapid and automatic swelling and consumption of the inner core also determine that the inner core is not easy to block the mill screen, and further avoid the problems of low production capacity and unstable mill power caused by the blocking of the mill screen by the fine grinding balls.

[0023] The application uses different forming slurries for the inner core, the transition layer and the outer layer respectively to adjust the performance of each layer and make the layers easy to combine with each other. Embodiment

[0024] The technical solutions in the embodiments of the application are described below clearly and completely.

[0025] Embodiment 1: A ceramic ball inner core which can hydrolyze, comprising the following raw materials in mass percentage: Al2O3: 5%, SiO2: 0.5%, ZrO2: 1%, MgO: 5%, CaO: 40%, BaO: 47.7%, SrO: 0.5%, Y2O3: 0.1%, CeO2: 0.2%.

[0026] Embodiment 2: A ceramic ball inner core which can hydrolyze, comprising the following raw materials in mass percentage: Al2O3: 10%, SiO2: 2%, ZrO2: 3%, MgO: 40%, CaO: 15%, BaO: 10%, SrO: 18.5%, Y2O3: 0.5%, CeO2: 1%.

[0027] Example 3: A ceramic ball inner core which can hydrolyze, comprising the following mass percentages of raw materials: Al2O3: 20%, SiO2: 1%, ZrO2: 2%, MgO: 6%, CaO: 50%, BaO: 10%, SrO: 10%, Y2O3: 0.5%, CeO2: 0.5%.

[0028] Example 4: A ceramic ball inner core which can hydrolyze, comprising the following mass percentages of raw materials: Al2O3: 8%, SiO2: 3%, ZrO2: 10%, MgO: 10%, CaO: 15%, BaO: 10%, SrO: 40%, Y2O3: 1%, CeO2: 3%.

[0029] Example 5: A ceramic ball inner core which can hydrolyze, comprising the following mass percentages of raw materials: Al2O3: 10%, SiO2: 3%, ZrO2: 7%, MgO: 8%, CaO: 15%, BaO: 50%, SrO: 6%, Y2O3: 0.7%, CeO2: 0.3%.

[0030] Example 6: A ceramic ball containing a ceramic ball inner core which can hydrolyze, characterized in that the ceramic ball is composed of an inner core, a transition layer and an outer layer from inside to outside; the transition layer is an inert layer.

[0031] Example 7: A method for preparing a ceramic ball containing a ceramic ball inner core which can hydrolyze,

[0032] Batching: Take the inner core raw materials, transition layer raw materials and outer layer raw materials; the inner core raw materials are the raw materials of Example 1, the transition layer raw materials are Al2O3, and the outer layer raw materials are ceramic powders with a sintering temperature of 1250℃, Al2O3: 45%, SiO2: 50.1%, MgO: 0.5%, CaO: 0.5%, K2O: 2.5%, Na2O: 0.6%, Fe2O3: 0.5%, TiO2: 0.3%.

[0033] Powder preparation: The inner core raw materials, transition layer raw materials and outer layer raw materials are respectively subjected to coarse grinding-fine grinding-spray drying to obtain inner core powder, transition layer powder and outer layer powder, the fineness of the inner core powder is 5-20 microns, the fineness of the transition layer powder is 2-10 microns, and the fineness of the outer layer powder is 1-5 microns.

[0034] Molding: using the rolling molding method, spraying the molding pulp water while feeding, the molding pulp water is divided into core molding pulp water, transition layer molding pulp water, outer layer molding pulp water, the core molding pulp water contains 0.2% Dow Acusol420N, 0.1% PVA2488, 0.1% Rohm & Haas ACUMER 9300; the transition layer molding pulp water contains 0.1% Dow Duramax B-1000 and 0.1% PVA2488; the outer layer molding pulp water contains 0.1% PVA2488, 0.05% sodium hexametaphosphate and 0.05% white sugar.

[0035] The ball blank slowly rolls and grows; first, the core powder is rolled and molded to 10% of the target ceramic ball size to obtain the core; then, the transition layer powder is replaced, and the core is coated and molded to 11% of the target ceramic ball size to obtain the core coated with the transition layer; finally, the outer layer powder is replaced, and the target particle size is coated and molded to obtain the target ceramic ball blank containing the core, the transition layer and the outer layer;

[0036] Firing: the firing temperature of the target ceramic ball blank is room temperature~350℃, the heating rate is 2℃ / min; 350~800℃, the heating rate is 1℃ / min; 800~1250℃, the heating rate is 8℃ / min; the highest temperature is kept for 5h, and then 8℃ / min is cooled to room temperature; the ceramic ball containing the core is obtained.

[0037] Example 7: a method for preparing a ceramic ball containing a hydrolyzable ceramic ball core,

[0038] Batching: taking the core raw material, the transition layer raw material and the outer layer raw material; the core raw material is the raw material of Example 2, the transition layer raw material is ZrO2; the outer layer raw material is a ceramic powder with a sintering temperature of 1300℃, which is Al2O3: 65%, SiO2: 30.7%, MgO: 1.5%, CaO: 1%, K2O: 1%, Na2O: 0.3%, Fe2O3: 0.4%, TiO2: 0.1%.

[0039] Powder preparation: the core raw material, the transition layer raw material and the outer layer raw material are respectively subjected to coarse grinding-fine grinding-spray drying to obtain the core powder, the transition layer powder and the outer layer powder, the fineness of the core powder is 5~20 microns, the fineness of the transition layer powder is 2~10 microns, and the fineness of the outer layer powder is 1~5 microns;

[0040] Molding: using the rolling molding method, spraying the molding pulp water while feeding, the molding pulp water is divided into core molding pulp water, transition layer molding pulp water, outer layer molding pulp water, the core molding pulp water contains 0.5% Dow Acusol 420N, 0.1~1% PVA2488, 0.3% Ronghais ACUMER 9300; the transition layer molding pulp water contains 0.5% Dow Duramax B-1000 and 0.5% PVA2488; the outer layer molding pulp water contains 0.5% PVA2488, 0.1% sodium hexametaphosphate and 0.1% white sugar.

[0041] The ball blank slowly rolls and grows; first, the core powder is rolled and molded to 20% of the target ceramic ball size to obtain the core; then, the transition layer powder is replaced, and the core is coated to 30% of the target ceramic ball size to obtain the core coated with the transition layer; finally, the outer layer powder is replaced, and the core is coated to the target size to obtain the target ceramic ball blank containing the core, the transition layer and the outer layer;

[0042] Firing: the firing temperature of the target ceramic ball blank is room temperature~350℃, the heating rate is 2℃ / min; 350~800℃, the heating rate is 1℃ / min; 800~1250℃, the heating rate is 8℃ / min; 1250~the highest temperature, the highest temperature is 1300℃, the heating rate is 1℃ / min; the highest temperature is kept for 5h, and then 8℃ / min is cooled to room temperature; the ceramic ball containing the core is obtained.

[0043] Example 9: a method for preparing a ceramic ball containing a hydrolyzable ceramic ball core,

[0044] Batching: taking the core raw material, the transition layer raw material and the outer layer raw material; the core raw material is the raw material of example 3, the transition layer raw material is a combination of Al2O3 and ZrO2; the outer layer raw material is a ceramic powder with a sintering temperature of 1400℃, which contains Al2O3: 35%, ZrO2: 53.6%, SiO2: 8%, MgO: 0.3%, CaO: 1%, K2O: 0.1%, Y2O3: 2%.

[0045] Powder preparation: the core raw material, the transition layer raw material and the outer layer raw material are respectively subjected to coarse grinding-fine grinding-spray drying to obtain the core powder, the transition layer powder and the outer layer powder, the fineness of the core powder is 5~20 microns, the fineness of the transition layer powder is 2~10 microns, and the fineness of the outer layer powder is 1~5 microns;

[0046] Molding: using rolling molding method, while feeding, spray the molding pulp water, the molding pulp water is divided into core molding pulp water, transition layer molding pulp water, outer layer molding pulp water, the core molding pulp water contains 0.8% Dow Acusol420N, 1% PVA2488, 0.5% Rongmenhas ACUMER 9300; the transition layer molding pulp water contains 1% Dow Duramax B-1000 and 1% PVA2488; the outer layer molding pulp water contains 1% PVA2488, 0.5% sodium hexametaphosphate and 0.2% white sugar.

[0047] The ball blank slowly rolls and grows; first, using the core powder to roll and mold to 30% of the target ceramic ball size, to obtain the core; then, replace the transition layer powder, coat and mold to 40% of the target ceramic ball size, to obtain the core coated with the transition layer; finally, replace the outer layer powder, coat and mold to the target size, to obtain the target ceramic ball blank containing the core, the transition layer and the outer layer;

[0048] Firing: the firing temperature of the target ceramic ball blank is room temperature~350℃, the heating rate is 2℃ / min; 350~800℃, the heating rate is 1℃ / min; 800~1250℃, the heating rate is 8℃ / min; 1250~the highest temperature, the highest temperature is 1400℃, the heating rate is 1℃ / min; the highest temperature is kept for 5h, and then 8℃ / min is cooled to room temperature; to obtain the core ceramic ball.

[0049] In the raw materials, the source of MgO can be one or a combination of magnesium carbonate, basic magnesium carbonate, magnesite, and dolomite; the source of CaO can be one or a combination of light calcium carbonate, heavy calcium carbonate, calcium nitrate, and dolomite; the source of BaO is barium carbonate; the source of SrO is strontium carbonate; the source of Al2O3 can be calcined alumina; the source of SiO2 can be quartz powder; the source of ZrO2 can be zirconium oxide.

[0050] The described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor belong to the scope of protection of the present application.

Claims

1. A method of producing a ceramic sphere containing a hydrolyzable core, characterized by, The ceramic ball is composed of a core, a transition layer and an outer layer from inside to outside; the method comprises the following steps: (1) batching: taking core raw materials, transition layer raw materials and outer layer raw materials; the core raw materials include the following raw materials in mass percentage: Al2O3: 5-20%, SiO2: 0.5-3%, ZrO2: 1-10%, MgO: 5-40%, CaO: 15-50%, BaO: 10-50%, SrO: 0.5-40%, Y2O3: 0.1-1%, CeO2: 0.2-3%, the transition layer raw materials are one or a combination of both of Al2O3 and ZrO2, and the outer layer raw materials are ceramic powder with a sintering temperature of 1250-1400℃; (2) powder preparation: the core raw materials, the transition layer raw materials and the outer layer raw materials are respectively subjected to coarse grinding, fine grinding and spray drying to obtain core powder, transition layer powder and outer layer powder, the fineness of the core powder is 5-20 microns, the fineness of the transition layer powder is 2-10 microns, and the fineness of the outer layer powder is 1-5 microns; (3) forming: using roll forming method to form, spraying forming slurry water while feeding, and the green ball slowly rolls and grows; first, using the core powder to form to 10-30% of the target ceramic ball size, to obtain the core; then, replacing the transition layer powder, coating forming to 11-40% of the target ceramic ball size, to obtain the core coated with the transition layer; finally, replacing the outer layer powder, coating forming to the target size, to obtain the target ceramic green body containing the core, the transition layer and the outer layer; (4) sintering: the sintering temperature of the target ceramic green body is room temperature-350℃, the heating rate is 2℃ / min; 350-800℃, the heating rate is 1℃ / min; 800-1250℃, the heating rate is 8℃ / min; 1250-highest temperature, the heating rate is 1℃ / min; the highest temperature is 1250-1400℃, the highest temperature is kept for 5h, and then 8℃ / min is used to reduce the temperature to room temperature; to obtain the core ceramic ball.