CN115974459B - Magnesium slag piezoelectric composite material and preparation method thereof - Google Patents
Magnesium slag piezoelectric composite material and preparation method thereof Download PDFInfo
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- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 title claims abstract description 132
- 239000002893 slag Substances 0.000 title claims abstract description 132
- 239000011777 magnesium Substances 0.000 title claims abstract description 131
- 229910052749 magnesium Inorganic materials 0.000 title claims abstract description 131
- 239000002131 composite material Substances 0.000 title claims abstract description 84
- 238000002360 preparation method Methods 0.000 title claims description 21
- 239000004793 Polystyrene Substances 0.000 claims abstract description 113
- 229920002223 polystyrene Polymers 0.000 claims abstract description 113
- 239000002241 glass-ceramic Substances 0.000 claims abstract description 36
- 239000002994 raw material Substances 0.000 claims abstract description 31
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 28
- 239000006254 rheological additive Substances 0.000 claims abstract description 17
- 238000003763 carbonization Methods 0.000 claims description 55
- 239000000203 mixture Substances 0.000 claims description 50
- 239000000463 material Substances 0.000 claims description 41
- 238000002156 mixing Methods 0.000 claims description 25
- 238000000518 rheometry Methods 0.000 claims description 19
- 238000000034 method Methods 0.000 claims description 17
- 239000002245 particle Substances 0.000 claims description 16
- 239000007788 liquid Substances 0.000 claims description 14
- 238000003756 stirring Methods 0.000 claims description 12
- 238000011049 filling Methods 0.000 claims description 11
- 238000009837 dry grinding Methods 0.000 claims description 10
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims description 7
- 238000010000 carbonizing Methods 0.000 claims description 7
- 238000000227 grinding Methods 0.000 claims description 7
- 229910001018 Cast iron Inorganic materials 0.000 claims description 6
- 229920002101 Chitin Polymers 0.000 claims description 5
- 229920001661 Chitosan Polymers 0.000 claims description 5
- 238000003825 pressing Methods 0.000 claims description 5
- 239000007787 solid Substances 0.000 claims description 5
- 229910002367 SrTiO Inorganic materials 0.000 claims description 4
- 229910052804 chromium Inorganic materials 0.000 claims description 4
- 239000011651 chromium Substances 0.000 claims description 4
- 229910001208 Crucible steel Inorganic materials 0.000 claims description 3
- 229910045601 alloy Inorganic materials 0.000 claims description 3
- 239000000956 alloy Substances 0.000 claims description 3
- 239000000919 ceramic Substances 0.000 claims description 3
- 229910003460 diamond Inorganic materials 0.000 claims description 3
- 239000010432 diamond Substances 0.000 claims description 3
- 238000000465 moulding Methods 0.000 claims description 3
- 229910000599 Cr alloy Inorganic materials 0.000 claims description 2
- 229910000831 Steel Inorganic materials 0.000 claims description 2
- 239000000788 chromium alloy Substances 0.000 claims description 2
- 239000004794 expanded polystyrene Substances 0.000 claims description 2
- 239000010959 steel Substances 0.000 claims description 2
- 230000003993 interaction Effects 0.000 abstract description 4
- 230000000052 comparative effect Effects 0.000 description 23
- 239000012298 atmosphere Substances 0.000 description 9
- 238000000748 compression moulding Methods 0.000 description 9
- 210000003298 dental enamel Anatomy 0.000 description 7
- 239000010935 stainless steel Substances 0.000 description 7
- 229910001220 stainless steel Inorganic materials 0.000 description 7
- 238000004519 manufacturing process Methods 0.000 description 6
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 3
- 229910052918 calcium silicate Inorganic materials 0.000 description 3
- 235000012241 calcium silicate Nutrition 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 239000004567 concrete Substances 0.000 description 3
- 239000010936 titanium Substances 0.000 description 3
- 229910052719 titanium Inorganic materials 0.000 description 3
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- BRPQOXSCLDDYGP-UHFFFAOYSA-N calcium oxide Chemical compound [O-2].[Ca+2] BRPQOXSCLDDYGP-UHFFFAOYSA-N 0.000 description 2
- 239000000292 calcium oxide Substances 0.000 description 2
- ODINCKMPIJJUCX-UHFFFAOYSA-N calcium oxide Inorganic materials [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 2
- JHLNERQLKQQLRZ-UHFFFAOYSA-N calcium silicate Chemical compound [Ca+2].[Ca+2].[O-][Si]([O-])([O-])[O-] JHLNERQLKQQLRZ-UHFFFAOYSA-N 0.000 description 2
- 230000032798 delamination Effects 0.000 description 2
- 239000006185 dispersion Substances 0.000 description 2
- 238000005265 energy consumption Methods 0.000 description 2
- 230000036571 hydration Effects 0.000 description 2
- 238000006703 hydration reaction Methods 0.000 description 2
- 239000000395 magnesium oxide Substances 0.000 description 2
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 2
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- 239000000758 substrate Substances 0.000 description 2
- 229910000851 Alloy steel Inorganic materials 0.000 description 1
- BHPQYMZQTOCNFJ-UHFFFAOYSA-N Calcium cation Chemical compound [Ca+2] BHPQYMZQTOCNFJ-UHFFFAOYSA-N 0.000 description 1
- 239000004743 Polypropylene Substances 0.000 description 1
- 238000003723 Smelting Methods 0.000 description 1
- 229920006125 amorphous polymer Polymers 0.000 description 1
- 229910001424 calcium ion Inorganic materials 0.000 description 1
- 239000000378 calcium silicate Substances 0.000 description 1
- OYACROKNLOSFPA-UHFFFAOYSA-N calcium;dioxido(oxo)silane Chemical compound [Ca+2].[O-][Si]([O-])=O OYACROKNLOSFPA-UHFFFAOYSA-N 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 150000001768 cations Chemical class 0.000 description 1
- 239000004568 cement Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- 239000002440 industrial waste Substances 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 229910000464 lead oxide Inorganic materials 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- YEXPOXQUZXUXJW-UHFFFAOYSA-N oxolead Chemical compound [Pb]=O YEXPOXQUZXUXJW-UHFFFAOYSA-N 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- -1 polypropylene Polymers 0.000 description 1
- 229920001155 polypropylene Polymers 0.000 description 1
- 238000009417 prefabrication Methods 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 159000000000 sodium salts Chemical class 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/91—Use of waste materials as fillers for mortars or concrete
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Abstract
The invention provides a magnesium slag piezoelectric composite material which is prepared from the following raw materials: 20-60 parts of magnesium slag; 5-65 parts of polystyrene; 20-55 parts of glass ceramic; 10 to 25 parts by weight of water; 0.05 to 0.5 weight portion of rheology modifier. Compared with the prior art, the magnesium slag piezoelectric composite material provided by the invention selects magnesium slag as a main raw material of the composite material, and is matched with other specific components with specific content to realize overall better interaction, so that the product has good mechanical property, piezoelectric property, volume stability and durability, and meanwhile, the magnesium slag can be reused with high efficiency and low cost.
Description
Technical Field
The invention relates to the technical field of piezoelectric composite materials, in particular to a magnesium slag piezoelectric composite material and a preparation method thereof.
Background
The piezoelectric composite material is a polymer piezoelectric material having piezoelectricity, and can obtain a piezoelectric material exhibiting the same piezoelectricity in any direction without a process such as stretching. This feature plays a very important role in the structural inspection of concrete. The requirements on the mechanical properties of the piezoelectric composite materials are gradually improved due to the continuous appearance of high-rise buildings and super high-rise buildings. The piezoelectric composite material applied to the concrete industry is generally a cement-based piezoelectric material, has wide application range, but has the problems of poor mechanical property, piezoelectric property and thermal stability, high loss, mismatching of the piezoelectric phase mechanical property and a matrix and the like for practical requirements at present.
Chinese patent CN114656256a discloses a piezoelectric composite material prepared by using titanium-containing ore and its method, and the invention provides a method for preparing piezoelectric composite material by using titanium-containing blast furnace slag, high titanium slag, lead oxide and sodium salt as raw materials and roasting in one step and two stages. The piezoelectric composite material and the concrete have good fusion property and excellent mechanical property and piezoelectric property, but the invention has the roasting process, so that the combustion energy cost is increased, and the production time cost is also increased in the one-step two-stage roasting process.
Disclosure of Invention
In view of the above, in order to solve the problem that the mechanical property and the piezoelectric property of the conventional composite material cannot be combined, the invention aims to provide the magnesium slag piezoelectric composite material and the preparation method thereof.
The invention provides a magnesium slag piezoelectric composite material which is prepared from the following raw materials:
20-60 parts of magnesium slag;
5-65 parts of polystyrene;
20-55 parts of glass ceramic;
10 to 25 parts by weight of water;
0.05 to 0.5 weight portion of rheology modifier.
Preferably, the particle size of the magnesium slag is 5-65 μm.
Preferably, the polystyrene is selected from one or more of general-purpose polystyrene, expanded polystyrene and impact-resistant polystyrene; the particle size of the polystyrene is 10-100 mu m.
Preferably, the polystyrene is composed of 10 to 55wt% of general-purpose polystyrene, 15 to 50wt% of foaming-grade polystyrene and 55 to 90wt% of impact-resistant-grade polystyrene,
Or alternatively, the first and second heat exchangers may be,
Consists of 10 to 45 weight percent of general-purpose polystyrene and 55 to 90 weight percent of impact-resistant polystyrene,
Or alternatively, the first and second heat exchangers may be,
Consists of 15 to 50 weight percent of foaming-grade polystyrene and 50 to 85 weight percent of impact-resistant-grade polystyrene,
Or alternatively, the first and second heat exchangers may be,
Consists of 50 to 80 weight percent of general-purpose polystyrene and 20 to 50 weight percent of foaming-grade polystyrene;
Or alternatively, the first and second heat exchangers may be,
Is impact-resistant polystyrene.
Preferably, the glass ceramic is SrTiO 3, and the grain size is 3-70 μm.
Preferably, the rheology modifier is selected from one or more of chitosan, chitin and chitin.
The invention also provides a preparation method of the magnesium slag piezoelectric composite material, which comprises the following steps:
a) Uniformly mixing magnesium slag, polystyrene and glass ceramic to obtain a mixture A; uniformly mixing a rheology regulator and water to obtain a mixture B;
b) Adding the mixture B into the mixture A, and stirring until solid and liquid are not layered to obtain a wet material;
c) Pressing and forming the wet material to obtain a blank;
d) And (3) placing the blank body into a carbonization device for carbonization to generate the magnesium slag piezoelectric composite material.
Preferably, the conditions of uniform mixing in step a) may also use a ball mill: the lining plate materials of the ball mill comprise but are not limited to chromium cast iron, medium chromium alloy steel and multi-element low-alloy diamond, the grinding balls comprise but are not limited to cast steel balls, high chromium cast iron and ceramic, the filling rate is 40-50%, the rotating speed of the ball mill cylinder is 18-20 r/min, and the grinding mixing time is 0.5-3 h for dry grinding.
Preferably, the press forming conditions in step c) are: the pressure is 10MPa to 50MPa, and the pressure maintaining time is 30s to 180s.
Preferably, the carbonization conditions in step d) are: carbonizing under CO 2 atmosphere with concentration higher than 5%, wherein the carbonization pressure is 0.1-0.6 MPa, and the carbonization time is 0.5-24 h.
The invention provides a magnesium slag piezoelectric composite material which is prepared from the following raw materials: 20-60 parts of magnesium slag; 5-65 parts of polystyrene; 20-55 parts of glass ceramic; 10 to 25 parts by weight of water; 0.05 to 0.5 weight portion of rheology modifier. Compared with the prior art, the magnesium slag piezoelectric composite material provided by the invention selects magnesium slag as a main raw material of the composite material, and is matched with other specific components with specific content to realize overall better interaction, so that the product has good mechanical property, piezoelectric property, volume stability and durability, and meanwhile, the magnesium slag can be reused with high efficiency and low cost.
In addition, the preparation method provided by the invention has the advantages of simple process, no roasting process, mild and easily controlled conditions and wide application prospect.
Detailed Description
The technical solutions of the present invention will be clearly and completely described in conjunction with the embodiments of the present invention, and it is apparent that the described embodiments are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
The invention provides a magnesium slag piezoelectric composite material which is prepared from the following raw materials:
20-60 parts of magnesium slag;
5-65 parts of polystyrene;
20-55 parts of glass ceramic;
10 to 25 parts by weight of water;
0.05 to 0.5 weight portion of rheology modifier.
In the invention, the magnesium slag piezoelectric composite material is prepared from raw materials including magnesium slag, polystyrene, glass ceramic, water and a rheology regulator, and is preferably prepared from magnesium slag, polystyrene, glass ceramic, water and a rheology regulator. The sources of the polystyrene, the glass ceramic and the rheology modifier are not particularly limited, and commercially available products well known to those skilled in the art can be used; the magnesium slag is industrial waste slag discharged in the smelting process of magnesium metal.
In the present invention, the particle diameter of the magnesium slag is preferably 5 μm to 65 μm, more preferably 20 μm to 40 μm. The invention selects magnesium slag as the main raw material of the composite material, can provide a magnesium slag piezoelectric composite material with the special property, has excellent mechanical property and piezoelectric property, and has wide application prospect.
In the present invention, the magnesium slag piezoelectric composite material includes 20 to 60 parts by weight of magnesium slag, preferably 30 to 40 parts by weight.
In the present invention, the polystyrene is preferably selected from one or more of general-purpose polystyrene, foaming-grade polystyrene and impact-resistant-grade polystyrene; in a preferred embodiment of the present invention, the polystyrene is composed of 10wt% to 55wt% of general-purpose polystyrene, 15wt% to 50wt% of foaming-grade polystyrene, and 55wt% to 90wt% of impact-resistant-grade polystyrene, preferably 15wt% of general-purpose polystyrene, 25wt% of foaming-grade polystyrene, and 60wt% of impact-resistant-grade polystyrene;
Or alternatively, the first and second heat exchangers may be,
Consists of 10 to 45wt% of general-purpose polystyrene and 55 to 90wt% of impact-resistant polystyrene, preferably 20wt% of general-purpose polystyrene and 80wt% of impact-resistant polystyrene;
Or alternatively, the first and second heat exchangers may be,
Consists of 15 to 50 weight percent of foaming-grade polystyrene and 50 to 85 weight percent of impact-resistant-grade polystyrene;
Or alternatively, the first and second heat exchangers may be,
Consists of 50 to 80 weight percent of general-purpose polystyrene and 20 to 50 weight percent of foaming-grade polystyrene;
Or alternatively, the first and second heat exchangers may be,
Is impact-resistant polystyrene.
In the present invention, the particle size of the polystyrene is preferably 10 μm to 100. Mu.m, more preferably 40 μm to 60. Mu.m.
In the present invention, the magnesium slag piezoelectric composite material includes 5 to 65 parts by weight of polystyrene, preferably 20 to 35 parts by weight.
In the present invention, the glass ceramic is preferably SrTiO 3, and the particle size is preferably 3 μm to 70. Mu.m.
In the present invention, the magnesium slag piezoelectric composite material includes 20 to 55 parts by weight of glass ceramic, preferably 25 to 35 parts by weight.
In the present invention, the rheology modifier is preferably one or more selected from chitosan, chitin and chitin, more preferably chitosan.
In the present invention, the magnesium slag piezoelectric composite material includes 0.05 to 0.5 parts by weight of a rheology modifier, preferably 0.15 to 0.2 parts by weight.
The magnesium slag piezoelectric composite material provided by the invention selects magnesium slag as a main raw material of the composite material, and is matched with other specific components with specific content, so that the overall better interaction is realized, the product has good mechanical property, piezoelectric property, volume stability and durability, and meanwhile, the high-efficiency and low-cost recycling of the magnesium slag is realized.
The invention also provides a preparation method of the magnesium slag piezoelectric composite material, which comprises the following steps:
a) Uniformly mixing magnesium slag, polystyrene and glass ceramic to obtain a mixture A; uniformly mixing a rheology regulator and water to obtain a mixture B;
b) Adding the mixture B into the mixture A, and stirring until solid and liquid are not layered to obtain a wet material;
c) Pressing and forming the wet material to obtain a blank;
d) And (3) placing the blank body into a carbonization device for carbonization to generate the magnesium slag piezoelectric composite material.
Firstly, uniformly mixing magnesium slag, polystyrene and glass ceramic to obtain a mixture A; and uniformly mixing the rheological modifier and water to obtain a mixture B.
In the present invention, the magnesium slag, polystyrene, glass ceramic, rheology modifier and water are the same as those in the above technical solution, and will not be described here again.
In the present invention, the conditions for uniform mixing may preferably further use a ball mill: the lining plate materials of the ball mill comprise but are not limited to chrome cast iron, medium chrome alloy steel and multi-element low-alloy diamond, the materials of the grinding balls comprise but are not limited to cast steel balls, high chrome cast iron and ceramic, the filling rate is preferably 40% -50%, more preferably 45%, the rotating speed of the ball mill cylinder is preferably 18-20 r/min, the grinding mixing time is preferably 0.5-3 h, more preferably 1h, and dry grinding is carried out.
According to the invention, the ball mill can more accurately control the particle size of each preparation material by adjusting and changing parameters such as filling rate, cylinder rotating speed, grinding mixing time and the like, and can also enable each material to be more fully mixed and dispersed more uniformly in the running process of a machine.
Then, adding the mixture B into the mixture A, and stirring until solid and liquid are not layered to obtain a wet material; and then pressing and forming the wet material to obtain a blank body.
In the present invention, the press molding conditions are preferably: the pressure is preferably 10MPa to 50MPa, and the dwell time is preferably 30s to 180s, more preferably 110s to 130s.
Finally, the blank is put into a carbonization device for carbonization to generate the magnesium slag piezoelectric composite material.
In the present invention, the carbonization conditions are preferably: carbonization is performed under a CO 2 atmosphere having a concentration of preferably more than 5%, more preferably 90%, and the carbonization pressure is preferably 0.1MPa to 0.6MPa, more preferably 0.3MPa to 0.5MPa, and the carbonization time is preferably 0.5h to 24h.
The preparation method provided by the invention comprises the steps of uniformly mixing all raw materials to prepare wet materials, and carrying out carbonization reaction in an environment rich in CO 2 after prefabrication and molding; the powder premixing compression molding mode is high in controllability, capable of improving the uniform dispersion degree of the piezoelectric phase in the matrix, excellent in mechanical property, high in production speed and low in energy consumption. The preparation method provided by the invention has the advantages of simple process, no roasting process, mild and easily controlled conditions and wide application prospect.
The invention has the following beneficial effects:
The invention adopts magnesium slag carbonization and hardening to form the piezoelectric composite material substrate, and the powder premixing compression molding mode has high controllable degree, can improve the uniform dispersion degree of the piezoelectric phase in the substrate, and has high production speed and low energy consumption.
The magnesium slag mineral belongs to a metastable high-temperature structure, active cations exist in the structure, so the magnesium slag has high hydration activity, hydrated calcium silicate gel is generated after hydration, the problem of solid-liquid delamination of the magnesium slag can be remarkably improved together with a rheology regulator, and the dissolution of calcium ions is promoted, so that the carbonization reaction is promoted; the magnesium slag contains a large amount of dicalcium silicate, a small amount of magnesium oxide and free calcium oxide, and can react with carbon dioxide in a proper carbonization environment to generate a compact carbonized product, so that the mechanical property and durability of a finished product material can be obviously improved; the conductive metal magnesium in the magnesium slag can also play a role in improving the piezoelectric performance of the finished product in the composite material, thereby being beneficial to the long-term development of the composite material; the magnesium slag is used as the main raw material, so that the cost is low, and the production cost can be reduced from the source.
The invention provides a magnesium slag piezoelectric composite material which is prepared from the following raw materials: 20-60 parts of magnesium slag; 5-65 parts of polystyrene; 20-55 parts of glass ceramic; 10 to 25 parts by weight of water; 0.05 to 0.5 weight portion of rheology modifier. Compared with the prior art, the magnesium slag piezoelectric composite material provided by the invention selects magnesium slag as a main raw material of the composite material, and is matched with other specific components with specific content to realize overall better interaction, so that the product has good mechanical property, piezoelectric property, volume stability and durability, and meanwhile, the magnesium slag can be reused with high efficiency and low cost.
In addition, the preparation method provided by the invention has the advantages of simple process, no roasting process, mild and easily controlled conditions and wide application prospect.
In order to further illustrate the present invention, the following examples are provided. The raw materials used in the following examples and comparative examples are all commercially available, wherein the glass ceramic is SrTiO 3, and the particle size is 45-55 mu m; the rheology modifier is chitosan.
Example 1
The raw materials of the magnesium slag piezoelectric composite material in the embodiment are as follows: the magnesium slag comprises, by weight, 30 parts of magnesium slag, 35 parts of polystyrene, 25 parts of glass ceramic, 15 parts of water and 0.15 part of a rheology regulator. The grain size of the magnesium slag is 30 mu m. The particle size of the polystyrene was 50. Mu.m. The polystyrene comprises the following three different types, which are mixed according to a certain mass ratio: 15% of general-purpose polystyrene, 25% of foaming-grade polystyrene and 60% of impact-resistant-grade polystyrene.
The preparation method comprises the following steps: firstly, crushing magnesium slag, carrying out dry grinding on the crushed magnesium slag and polystyrene and glass ceramic in an enamel ball mill with the filling rate of 45% for 1h at the rotating speed of 20r/min, taking out the mixture to obtain a mixture A, then mixing the mixture A with water and a rheology regulator in proportion, stirring the mixture B until no solid-liquid layering exists, obtaining a wet material, placing the wet material in a stainless steel carbonization mold, carrying out pressure of 50MPa for 120s, carrying out compression molding to obtain a blank, immediately placing the obtained blank into a carbonization device, carbonizing the blank under the CO 2 atmosphere with the purity of 90%, wherein the carbonization pressure is 0.4MPa, and the carbonization time is 24h, and obtaining the magnesium slag piezoelectric composite material.
Through testing, the technical indexes of the magnesium slag piezoelectric composite material prepared by the embodiment are as follows: the 24h compressive strength is 46.50MPa, the piezoelectric strain constant d33 is 95.20pC/N, the piezoelectric voltage constant g33 is 72.18 (mv) m/N, the relative dielectric constant E33 is 134.33, and the dielectric loss tan delta is 0.41, so that the material has excellent mechanical property and piezoelectric property.
Example 2
The raw materials of the magnesium slag piezoelectric composite material in the embodiment are as follows: the magnesium slag comprises, by weight, 40 parts of magnesium slag, 25 parts of polystyrene, 30 parts of glass ceramic, 20 parts of water and 0.2 part of a rheology regulator. The grain size of the magnesium slag is 30 mu m. The particle size of the polystyrene was 50. Mu.m. The polystyrene comprises the following two different types, which are mixed according to a certain mass ratio: 20% of general-purpose polystyrene and 80% of impact-resistant polystyrene.
The preparation method comprises the following steps: firstly, crushing magnesium slag, carrying out dry grinding on the crushed magnesium slag and polystyrene and glass ceramic in an enamel ball mill with the filling rate of 45% for 1h at the rotating speed of 20r/min, taking out the mixture to obtain a mixture A, then mixing the mixture A with water and a rheology regulator in proportion, stirring the mixture B until no solid-liquid layering exists, obtaining a wet material, placing the wet material in a stainless steel carbonization mold, carrying out pressure of 50MPa for 120s, carrying out compression molding to obtain a blank, immediately placing the obtained blank into a carbonization device, carbonizing the blank under the CO 2 atmosphere with the purity of 90%, wherein the carbonization pressure is 0.4MPa, and the carbonization time is 24h, and obtaining the magnesium slag piezoelectric composite material.
Through testing, the technical indexes of the magnesium slag piezoelectric composite material prepared by the embodiment are as follows: the compressive strength for 24 hours is 50.20MPa, the piezoelectric strain constant d33 is 92.30pC/N, the piezoelectric voltage constant g33 is 70.05 (mv) m/N, the relative dielectric constant E33 is 136.00, and the dielectric loss tan delta is 0.35, so that the material has excellent mechanical property and piezoelectric property.
Example 3
The raw materials of the magnesium slag piezoelectric composite material in the embodiment are as follows: the composite material comprises, by weight, 35 parts of magnesium slag, 20 parts of polystyrene, 35 parts of glass ceramic, 20 parts of water and 0.2 part of a rheology regulator. The grain size of the magnesium slag is 30 mu m. The particle size of the polystyrene was 50. Mu.m. Polystyrene is composed of one type of impact-resistant grade polystyrene.
The preparation method comprises the following steps: firstly, crushing magnesium slag, carrying out dry grinding on the crushed magnesium slag and polystyrene and glass ceramic in an enamel ball mill with the filling rate of 45% for 1h at the rotating speed of 20r/min, taking out the mixture to obtain a mixture A, then mixing the mixture A with water and a rheology regulator in proportion, stirring the mixture B until no solid-liquid layering exists, obtaining a wet material, placing the wet material in a stainless steel carbonization mold, carrying out pressure of 50MPa for 120s, carrying out compression molding to obtain a blank, immediately placing the obtained blank into a carbonization device, carbonizing the blank under the CO 2 atmosphere with the purity of 90%, wherein the carbonization pressure is 0.4MPa, and the carbonization time is 24h, and obtaining the magnesium slag piezoelectric composite material.
Through testing, the technical indexes of the magnesium slag piezoelectric composite material prepared by the embodiment are as follows: the 24h compressive strength is 53.50MPa, the piezoelectric strain constant d33 is 90.05pC/N, the piezoelectric voltage constant g33 is 70.00 (mv) m/N, the relative dielectric constant E33 is 130.80, and the dielectric loss tan delta is 0.38, so that the material has excellent mechanical property and piezoelectric property.
Comparative example 1
This comparative example was reduced in weight fraction of magnesium slag as a raw material only as compared with example 1, and other raw materials and preparation methods were not different from example 1.
The raw materials of the magnesium slag piezoelectric composite material in the comparative example are as follows: the magnesium slag comprises, by weight, 5 parts of magnesium slag, 35 parts of polystyrene, 25 parts of glass ceramic, 15 parts of water and 0.15 part of a rheology regulator. The grain size of the magnesium slag is 30 mu m. The particle size of the polystyrene was 50m. The polystyrene comprises the following three different types, which are mixed according to a certain mass ratio: 15% of general-purpose polystyrene, 25% of foaming-grade polystyrene and 60% of impact-resistant-grade polystyrene.
The preparation method comprises the following steps: firstly, crushing magnesium slag, carrying out dry grinding on the crushed magnesium slag and polystyrene and glass ceramic in an enamel ball mill with the filling rate of 45% for 1h at the rotating speed of 20r/min, taking out the mixture to obtain a mixture A, then mixing the mixture A with water and a rheology regulator in proportion, stirring the mixture B until no solid-liquid layering exists, obtaining a wet material, placing the wet material in a stainless steel carbonization mold, carrying out pressure of 50MPa for 120s, carrying out compression molding to obtain a blank, immediately placing the obtained blank into a carbonization device, carbonizing the blank under the CO 2 atmosphere with the purity of 90%, wherein the carbonization pressure is 0.4MPa, and the carbonization time is 24h, and obtaining the magnesium slag piezoelectric composite material.
Through testing, the technical indexes of the magnesium slag piezoelectric composite material prepared by the comparative example are as follows: the 24-hour compressive strength is 21.05MPa, the piezoelectric strain constant d33 is 58.50pC/N, the piezoelectric voltage constant g33 is 42.00 (mv) m/N, the relative dielectric constant E33 is 58.50, and the dielectric loss tan delta is 0.49.
Comparative example 2
In this comparative example, compared with example 1, only the raw material glass ceramic was not added, and other raw materials and production methods were not different from example 1.
The raw materials of the magnesium slag piezoelectric composite material in the comparative example are as follows: 30 parts of magnesium slag, 35 parts of polystyrene, 15 parts of water and 0.15 part of rheology modifier. The grain size of the magnesium slag is 30 mu m. The particle size of the polystyrene was 50. Mu.m. The polystyrene comprises the following three different types, which are mixed according to a certain mass ratio: 15% of general-purpose polystyrene, 25% of foaming-grade polystyrene and 60% of impact-resistant-grade polystyrene.
The preparation method comprises the following steps: firstly, crushing magnesium slag, carrying out dry grinding on the crushed magnesium slag and polystyrene in an enamel ball mill with the filling rate of 45% for 1h at the rotating speed of 20r/min, taking out the mixture to obtain a mixture A, then mixing the mixture A with a mixture B mixed with water and a rheology regulator in proportion, stirring the mixture B until no solid-liquid layering exists, obtaining a wet material, placing the wet material in a stainless steel carbonization mold, carrying out pressure maintaining for 120s at 50MPa, carrying out compression molding to obtain a blank body, immediately placing the obtained blank body in a carbonization device, carbonizing the blank body under the CO 2 atmosphere with the purity of 90%, wherein the carbonization pressure is 0.4MPa, and the carbonization time is 24h, thus obtaining the magnesium slag piezoelectric composite material.
Through testing, the technical indexes of the magnesium slag piezoelectric composite material prepared by the comparative example are as follows: the 24-hour compressive strength is 25.00MPa, the piezoelectric strain constant d33 is 62.00pC/N, the piezoelectric voltage constant g33 is 42.50 (mv) m/N, the relative dielectric constant E33 is 48.50, and the dielectric loss tan delta is 0.65.
Comparative example 3
In this comparative example, only the raw material of polypropylene was not added as compared with example 1, and other raw materials and production methods were not different from example 1.
The raw materials of the magnesium slag piezoelectric composite material in the comparative example are as follows: 30 parts of magnesium slag, 25 parts of glass ceramic, 15 parts of water and 0.15 part of rheology regulator. The grain size of the magnesium slag is 30 mu m.
The preparation method comprises the following steps: firstly, smashing magnesium slag, then, carrying out dry grinding on the smashed magnesium slag and glass ceramic in an enamel ball mill with the filling rate of 45% at the rotating speed of 20r/min for 1h, taking out the mixture to obtain a mixture A, then, mixing the mixture A with a mixture B mixed with water and a rheology regulator according to a proportion, stirring the mixture B until no solid-liquid layering exists, obtaining a wet material, placing the wet material in a stainless steel carbonization mold for compression molding to obtain a green body, immediately placing the obtained green body into a carbonization device for carbonization under the CO 2 atmosphere with the purity of 90%, wherein the carbonization pressure is 0.4MPa, and the carbonization time is 24h, thus obtaining the magnesium slag piezoelectric composite material.
Through testing, the technical indexes of the magnesium slag piezoelectric composite material prepared by the comparative example are as follows: the 24-hour compressive strength is 32.00MPa, the piezoelectric strain constant d33 is 65.80pC/N, the piezoelectric voltage constant g33 is 58.50 (mv) m/N, the relative dielectric constant E33 is 105.00, and the dielectric loss tan delta is 0.75.
Comparative example 4
In this comparative example, as compared with example 1, only the raw material rheology modifier was not added, and other raw materials and preparation methods were not different from example 1.
The raw materials of the magnesium slag piezoelectric composite material in the comparative example are as follows: the glass ceramic comprises, by weight, 30 parts of magnesium slag, 35 parts of polystyrene, 25 parts of glass ceramic and 15 parts of water. The grain size of the magnesium slag is 30 mu m. The particle size of the polystyrene was 50. Mu.m. The polystyrene comprises the following three different types, which are mixed according to a certain mass ratio: 15% of general-purpose polystyrene, 25% of foaming-grade polystyrene and 60% of impact-resistant-grade polystyrene.
The preparation method comprises the following steps: firstly, crushing magnesium slag, carrying out dry grinding on the crushed magnesium slag and polystyrene and glass ceramic in an enamel ball mill with the filling rate of 45% for 1h at the rotating speed of 20r/min, taking out the mixture to obtain a mixture A, then mixing the mixture A with water, stirring the mixture to be free of solid-liquid layering to obtain a wet material, placing the wet material in a stainless steel carbonization mold for compression molding to obtain a green body, immediately placing the prepared green body into a carbonization device for carbonization under the CO 2 atmosphere with the purity of 90%, wherein the carbonization pressure is 0.4MPa, and the carbonization time is 24h, thus obtaining the magnesium slag piezoelectric composite material.
Through testing, the technical indexes of the magnesium slag piezoelectric composite material prepared by the comparative example are as follows: the 24-hour compressive strength is 42.20MPa, the piezoelectric strain constant d33 is 69.00pC/N, the piezoelectric voltage constant g33 is 55.50 (mv) m/N, the relative dielectric constant E33 is 108.50, and the dielectric loss tan delta is 0.45.
The mechanical properties and piezoelectric properties of the piezoelectric composites prepared in examples 1 to 3 and comparative examples 1 to 4 of the present invention were examined, and the results are shown in table 1 below.
Table 1 data on mechanical properties and piezoelectric properties of the piezoelectric composites prepared in examples 1 to 3 and comparative examples 1 to 4 of the present invention
The mechanical properties and the piezoelectric properties of the magnesium slag piezoelectric composite materials prepared in the examples 1, 2 and 3 are obviously superior to those of the magnesium slag piezoelectric composite material prepared in the comparative example 1, and it is known that reducing the magnesium slag fraction reduces the contents of dicalcium silicate, magnesium oxide, free calcium oxide and conductive metal magnesium in the piezoelectric composite material, the carbonization reaction is insufficient, the yield of dense carbide is reduced, and the mechanical properties and the piezoelectric properties of the piezoelectric composite material are greatly reduced. The mechanical property and the piezoelectric property of the magnesium slag piezoelectric composite material prepared in the embodiment 1 are obviously superior to those of the comparative example 2, and the glass ceramic has the characteristics of high dielectric constant, low dielectric loss, good thermal stability and the like. The addition of glass ceramic is removed, the volume stability of the piezoelectric composite material is insufficient, the dielectric loss is increased, and the piezoelectric performance is reduced. Meanwhile, the mechanical property and the piezoelectric property of the magnesium slag piezoelectric composite material prepared in the embodiment 1 are obviously superior to those of the comparative example 3 and the comparative example 4, and the control of the addition of the polystyrene and the rheology regulator according to the weight fraction can play an important role in the key performance index of the piezoelectric composite material. The polystyrene has good dimensional stability and low shrinkage, and can ensure the volume stability of the composite material. As an amorphous polymer, polystyrene can also be used with rheology modifiers to significantly improve magnesium slag solids-liquid delamination. Therefore, the addition of polystyrene or rheological agent is removed to ensure insufficient combination of magnesium slag and other materials and uneven mixing, so that the mechanical property of the piezoelectric composite material is reduced due to uneven stress. Meanwhile, the maldistribution of materials can greatly reduce the piezoelectric performance.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (10)
1. The magnesium slag piezoelectric composite material is characterized by being prepared from the following raw materials:
20-60 parts of magnesium slag;
5-65 parts of polystyrene;
20-55 parts of glass ceramic;
10-25 parts of water;
0.05-0.5 parts by weight of a rheology modifier;
The preparation method of the magnesium slag piezoelectric composite material comprises the following steps:
a) Uniformly mixing magnesium slag, polystyrene and glass ceramic to obtain a mixture A; uniformly mixing a rheology regulator and water to obtain a mixture B;
b) Adding the mixture B into the mixture A, and stirring until solid and liquid are not layered to obtain a wet material;
c) Pressing and forming the wet material to obtain a blank;
d) And (3) placing the blank body into a carbonization device for carbonization to generate the magnesium slag piezoelectric composite material.
2. The magnesium slag piezoelectric composite material according to claim 1, wherein the particle size of the magnesium slag is 5-65 μm.
3. The magnesium slag piezoelectric composite material according to claim 1, wherein the polystyrene is selected from one or more of general-purpose polystyrene, expanded polystyrene, and impact-resistant polystyrene; the particle size of the polystyrene is 10-100 mu m.
4. The magnesium slag piezoelectric composite material according to claim 3, wherein the polystyrene is composed of 10wt% to 55wt% of general-purpose polystyrene, 15wt% to 50wt% of foam-grade polystyrene and 55wt% to 90wt% of impact-resistant-grade polystyrene, and the sum of the percentages of the general-purpose polystyrene, the foam-grade polystyrene and the impact-resistant-grade polystyrene is 100wt%;
Or alternatively, the first and second heat exchangers may be,
Consists of 10 to 45 weight percent of general-purpose polystyrene and 55 to 90 weight percent of impact-resistant polystyrene,
Or alternatively, the first and second heat exchangers may be,
Consists of 15-50 wt% of foaming-grade polystyrene and 50-85 wt% of impact-resistant-grade polystyrene,
Or alternatively, the first and second heat exchangers may be,
Consists of 50-80 wt% of general-purpose polystyrene and 20-50 wt% of foaming-grade polystyrene;
Or alternatively, the first and second heat exchangers may be,
Is impact-resistant polystyrene.
5. The magnesium slag piezoelectric composite material according to claim 1, wherein the glass ceramic is SrTiO 3, and the particle size is 3 μm to 70 μm.
6. The magnesium slag piezoelectric composite material according to claim 1, wherein the rheology modifier is selected from one or more of chitosan and chitin.
7. A method for preparing the magnesium slag piezoelectric composite material according to any one of claims 1 to 6, comprising the following steps:
a) Uniformly mixing magnesium slag, polystyrene and glass ceramic to obtain a mixture A; uniformly mixing a rheology regulator and water to obtain a mixture B;
b) Adding the mixture B into the mixture A, and stirring until solid and liquid are not layered to obtain a wet material;
c) Pressing and forming the wet material to obtain a blank;
d) And (3) placing the blank body into a carbonization device for carbonization to generate the magnesium slag piezoelectric composite material.
8. The method according to claim 7, wherein the uniformly mixed condition in step a) uses a ball mill: the lining plate material of the ball mill comprises chromium cast iron, medium chromium alloy steel and multiple low alloy diamond, the material of the grinding ball comprises cast steel balls, high chromium cast iron and ceramic, the filling rate is 40% -50%, the rotation speed of the ball mill cylinder is 18-20 r/min, and the grinding mixing time is 0.5-3 h for dry grinding.
9. The method according to claim 7, wherein the press molding conditions in step c) are: the pressure is 10-50 MPa, and the pressure maintaining time is 30-180 s.
10. The method according to claim 7, wherein the carbonization conditions in step d) are: carbonizing under CO 2 with concentration higher than 5%, wherein the carbonization pressure is 0.1-0.6 MPa, and the carbonization time is 0.5-24 h.
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| CN110436834A (en) * | 2019-07-17 | 2019-11-12 | 广州大学 | A kind of piezo-electricity composite material and piezoelectric patches prepared therefrom |
| CN115028394A (en) * | 2022-05-26 | 2022-09-09 | 武汉理工大学 | Magnesium slag 3D printing material and preparation and application thereof |
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| CN101045618A (en) * | 2006-03-27 | 2007-10-03 | 肖力光 | Small hollow building blocks made by magnesium waste slag and production method |
| CN106206928A (en) * | 2016-07-07 | 2016-12-07 | 南京信息工程大学 | A kind of piezoelectricity function porous electrode composite and preparation method |
| CN110436834A (en) * | 2019-07-17 | 2019-11-12 | 广州大学 | A kind of piezo-electricity composite material and piezoelectric patches prepared therefrom |
| CN115028394A (en) * | 2022-05-26 | 2022-09-09 | 武汉理工大学 | Magnesium slag 3D printing material and preparation and application thereof |
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