Classifications

• • C—CHEMISTRY; METALLURGY
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  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
  • C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
  • C04B35/16—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on silicates other than clay
  • C04B35/20—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on silicates other than clay rich in magnesium oxide, e.g. forsterite
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  • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
  • C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
  • C04B35/03—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on magnesium oxide, calcium oxide or oxide mixtures derived from dolomite
  • C04B35/04—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on magnesium oxide, calcium oxide or oxide mixtures derived from dolomite based on magnesium oxide
  • C04B35/043—Refractories from grain sized mixtures
  • C04B35/0435—Refractories from grain sized mixtures containing refractory metal compounds other than chromium oxide or chrome ore
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  • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
  • C04B35/66—Monolithic refractories or refractory mortars, including those whether or not containing clay
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  • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
  • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
  • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
  • C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
  • C04B2235/3205—Alkaline earth oxides or oxide forming salts thereof, e.g. beryllium oxide
  • C04B2235/3206—Magnesium oxides or oxide-forming salts thereof
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  • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
  • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
  • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
  • C04B2235/34—Non-metal oxides, non-metal mixed oxides, or salts thereof that form the non-metal oxides upon heating, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
  • C04B2235/3427—Silicates other than clay, e.g. water glass
  • C04B2235/3436—Alkaline earth metal silicates, e.g. barium silicate
  • C04B2235/3445—Magnesium silicates, e.g. forsterite
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  • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
  • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
  • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
  • C04B2235/38—Non-oxide ceramic constituents or additives
  • C04B2235/3817—Carbides
  • C04B2235/3826—Silicon carbides
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  • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
  • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
  • C04B2235/50—Constituents or additives of the starting mixture chosen for their shape or used because of their shape or their physical appearance
  • C04B2235/54—Particle size related information
  • C04B2235/5418—Particle size related information expressed by the size of the particles or aggregates thereof
  • C04B2235/5427—Particle size related information expressed by the size of the particles or aggregates thereof millimeter or submillimeter sized, i.e. larger than 0,1 mm
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  • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
  • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
  • C04B2235/50—Constituents or additives of the starting mixture chosen for their shape or used because of their shape or their physical appearance
  • C04B2235/54—Particle size related information
  • C04B2235/5418—Particle size related information expressed by the size of the particles or aggregates thereof
  • C04B2235/5436—Particle size related information expressed by the size of the particles or aggregates thereof micrometer sized, i.e. from 1 to 100 micron
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  • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
  • C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
  • C04B2235/656—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes characterised by specific heating conditions during heat treatment
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  • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
  • C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
  • C04B2235/96—Properties of ceramic products, e.g. mechanical properties such as strength, toughness, wear resistance
• • C—CHEMISTRY; METALLURGY
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  • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
  • C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
  • C04B2235/96—Properties of ceramic products, e.g. mechanical properties such as strength, toughness, wear resistance
  • C04B2235/9607—Thermal properties, e.g. thermal expansion coefficient

Definitions

• the present disclosure relates generally to a composition for a refractory article such as a refractory brick. More particularly, the present disclosure relates to a refractory article / brick composition having enhanced chemical infiltration resistance, anti-hydration, and low heat conductivity properties. Additionally, the present disclosure relates to a method for producing a refractory article / brick according to the composition disclosed herein.
• Refractory bricks, fire bricks or firebricks have been widely used in lining furnaces, kilns, fireboxes, and fireplaces. Desirable properties for their performance include ability to withstand high temperature while having a very low thermal conductivity for optimal energy efficiency; high Pyrometric Cone Equivalent (PCE) under load (typically higher than 2,000 °C); high thermal shock resistance; lightweight; high mechanical strength and toughness at wide temperature range; and high chemical resistance as well as high abrasion and corrosion resistance.
• PCE Pyrometric Cone Equivalent
• the pursuit of benefits and advantages of high performance refractory bricks has led to various research and development efforts over the years to improve the performance of refractory bricks. In particular, research has been conducted in an effort to ideally have or achieve all of the above-mentioned desirable properties.
• refractory bricks require protection from hydration due to water in the surrounding environment or water in liquid form either during storage or transportation and other logistical conditions. Essentially, refractory brick production requires an adequately maintained atmosphere for storage to minimize or avoid water contact or moisture absorption to prevent spontaneous cracking caused by hydration phenomena. In certain instances, finished refractory brick products are fully covered with packing materials or sheets and stored on wooden pallets.
• embodiments are directed towards a composition for a refractory article comprising olivine 40-90 % by weight of dry admixture, elastifier 5-35 % by weight of dry admixture, silicon carbide 1 - 15 % by weight of dry admixture, and magnesia to make up to 100% by weight of dry admixture.
• a refractory article having the composition as disclosed herein illustrates at least one of increased anti-hydration, thermal conductivity and chemical infiltration resistance properties. More specifically, the degree of anti-hydration property of the refractory article composition is between 1 -4 according to ASTM C456-93.
• the refractory article according to embodiments of the present disclosure exhibits a thermal conductivity having a value below 3.00 W/m at the temperature range of 200 - 1200 °C and/or an average permeability of the refractory article is in the range of 3 - 7 cD.
• the third aspect of the present disclosure includes a process for manufacturing a refractory article comprising providing predetermined amounts of olivine, elastifier, magnesia, and SiC; mixing olivine, elastifier, magnesia, and SiC provided; molding the mixed composition to form a final refractory article (e.g., a refractory brick or other type of refractory object); and firing the refractory article at the predetermined temperature wherein the final refractory article comprises of olivine 50-70 % by weight of dry admixture; elastifier 10-25 % by weight of dry admixture, silicon carbide 1 -5 % by weight of dry admixture, and magnesia to make up to 100% by weight of dry admixture, and said final refractory article is characterized in that at least one of anti-hydration, thermal conductivity and chemical infiltration resistance properties has been enhanced.
• FIG. 1 is a representative process for preparing, manufacturing, producing or obtaining a refractory article according to an embodiment of the present disclosure
• FIG. 2 is a rating scale of hydration of refractory articles tested in representative Example One described below;
• FIG. 3 is a correlation between thermal conductivity values and temperatures of refractory articles for refractory brick compositions according to the present disclosure and other conventional refractory brick compositions;
• FIG. 4 is a Scanning Electron Micrograph and Energy Dispersive X-ray of a refractory brick specimen of the present disclosure.
• Embodiments of the present disclosure are directed to a refractory article composition, such as a refractory brick composition, in which silicon carbide (SiC) primarily serves as an anti-hydration agent while simultaneously enhancing other refractory article / brick performance-associated properties, including low thermal conductivity and high chemical infiltration, and aiding or simplifying logistics issues associated with refractory articles / bricks such as refractory article / brick storage and transportation.
• SiC silicon carbide
• refractory brick composition can correspond or refer to or mean a refractory object or brick composition or one or more portions of a refractory object or brick in accordance with an embodiment of the present disclosure.
• all percentages (%) are percent weight-by-weight, which may also be expressed as % by weight, % (w/w) or simply %.
• dry admixture refers to the relative percentages of the constituents or components of the dry composition separate from or prior to the (intentional) addition of water and any liquid state reagent(s). Unless otherwise stated, percentage by weight herein refers to a dry admixture. A person of ordinary skill in the art will understand the manner in which wet admixture and dry admixture weight percentages are related or convertible.
• a refractory article / brick composition in accordance with the present disclosure can include (in a dry admixture): ( 1 ) olivine 40-90 % by weight, (2) spinel 5-35 % by weight, (3) SiC 1 - 15% by weight, and (4) Magnesia to make a total of 100% by weight.
• Embodiments of the present disclosure employ naturally raw olivine substance, [e.g., magnesium iron silicate with the formula (Mg +2 , Fe +2 ) 2 Si0 4 ], which is commercially available in the market with specified grain size ranging from fine to coarse grains.
• the olivine substance used in the refractory brick composition has a Gaussian grain-size distribution. It will be understood by persons having ordinary skill in the relevant art that synthetic olivine can also be used alone or in combination with naturally raw olivine.
• the two endmembers of olivine namely: forsterite (Mg- endmember: Mg 2 Si0 4 ) and fayalite (Fe-endmember: Fe 2 Si04) can be specified or selected upon formulating the refractory brick composition.
• forsterite may be selected at 75% or 100% and the remainder is favalite at 25% or 0%. Minor impurities are acceptable including enstatite, monticellite, and/or merwinite.
• a refractory brick composition in accordance with the present disclosure has olivine at the amount of 40-90%, or more particularly in several embodiments, 45- 80%.
• olivine content in the present disclosure is selected to be 50 - 70 %.
• Embodiments of the present disclosure further include an elastifier at the amount of 5- 35% by weight.
• Elastifiers can be selected from a group of spinel, magnesia alumina, Hercynite, or magnesia chrome. More preferably, magnesium spinel or spinel (collectively referred hereafter as "spinel") with a chemical formula MgAI 2 0 4 is incorporated at the amount of 5-35%, or more specifically in various embodiments at the amount of 10-25%, to form a refractory brick composition in accordance with the present disclosure.
• spinel magnesium spinel or spinel
• olivine content in the present disclosure is selected to be 18%.
• Embodiments of the present disclosure also include silicon carbide (SiC) or carborundum.
• the amount of SiC in the refractory brick composition in various embodiments of the present disclosure is determined at 1 - 15%, or 3- 10%, or more specifically 3-5% depending upon embodiment details.
• FIG. 1 is a flowchart of a representative process 100 for preparing, manufacturing, producing or obtaining a refractory article such as a refractory brick having a composition according to an embodiment of the present disclosure.
• the process 100 for preparing, manufacturing, producing or obtaining a refractory article according to an embodiment of the present disclosure typically occurs in a batch-wise manner.
• a predetermined volume of each of the constituents namely olivine, spinel, magnesia, and SiC are provided or introduced.
• each or some or all of the constituents can be crushed into a target particle size and/or particle size distribution, for instance, in the range from 10 micron to 5 millimeter.
• Each of the constituents can be screened (e.g. by way of a sieve) and preconditioned to achieve desirable or intended particle size, particle size distribution, and/or moisture content.
• the ratio or weight percentage of each of the constituents can be determined, specified, or selected and undergone a mixing step in a third process portion 130.
• a ball mill can be utilized for making fine particles while a jaw crushing machine or jaw crusher may be used for coarse particles or granules.
• the resulting admixture obtained can be molded, pressed, or shaped into a target shape to form a refractory brick, article, or product in a fourth process portion 140.
• the pressed or shaped refractory article can be dried by entering into a dryer including an air dry technique in a fifth process portion 150.
• the refractory article is fired at a temperature of 950 - 1 ,450 °C.
• the refractory article is fired at a temperature of 1 ,000 - 1 ,400 °C.
• the refractory article is fired at a temperature of 1 ,200 - 1 ,350 °C.
• a final refractory article, item, object, or product is obtained and can be packed and stored for distribution. It is further noted that refractory articles having a composition according to the present disclosure can be produced or obtained from either a molded or unmolded batch.
• Anti-hydration property test Effect ofSiC content incorporated in a refractory brick Experiments were conducted to evaluate, measure, and determine anti-hydration properties or characteristics of a refractory brick having a composition according to an embodiment of the present disclosure. Anti-hydration properties were tested by utilizing pressure and heat as an accelerator for hydration reaction according to ASTM C456-93: "Standard Test Method for Hydration Resistance of Basic Bricks and Shapes". In brief, ASTM C456-93 covers measurement of the relative resistance of basic brick and shapes to hydration.
• refractory brick compositions namely refractory brick compositions (A), (B), (C), (D), (E) and (F), were prepared having a size of 1 x 1 x 1 inch.
• Each refractory brick composition tested in Example One had constant weight percentage of olivine and spinel while varying SiC amount from 0-15 % by weight, hence a slight difference in magnesia content to make a total composition up to 100 % by weight.
• Details of refractory brick compositions (A) - (F) are as follows: Refractory brick composition (A)
• Refractory brick composition (A) included approximately 60% Olivine, 30% Magnesia, 10% Spinel, and 0% SiC by weight.
• Refractory brick composition (B) included approximately 60% Olivine, 29% Magnesia, 10% Spinel, and 1 % SiC by weight.
• Refractory brick composition (C) included approximately 60% Olivine, 29% Magnesia, 10% Spinel, and 1 % SiC by weight.
• Refractory brick composition (C) included approximately 60% Olivine, 27% Magnesia, 10% Spinel, and 3% SiC by weight.
• Refractory brick composition (D) included approximately 60% Olivine, 25% Magnesia, 10% Spinel, and 5% SiC by weight.
• Refractory brick composition (E) included approximately 60% Olivine, 20% Magnesia, 10% Spinel, and 10% SiC by weight.
• Refractory brick composition (F) included approximately 60% Olivine, 1 5% Magnesia, 10% Spinel, and 15% SiC by weight.
• refractory bricks were produced according to the process 100 previously described with above-described formulations, and more specifically, at three different firing temperatures, namely, 1 ,200 1 ,300 and 1 ,400 °C and at varying three firing intervals or durations, namely 60, 180 or 300 minutes.
• a selection of position to cut a testing specimen from each produced refractory brick was carefully considered to minimize error. More particularly, position numbers 3, 4, 9, 10, 15, 16, 21 , and 22 according to the below representation, were chosen for testing.
• testing specimens were placed in an autoclave chamber at a pressure of 80 psi (552 kPa) and temperature of 324 °F ( 162 °C), and equipped with pressure- and temperature- measuring devices, a vent cock, and safety equipment.
• the testing protocol starts with heating the autoclave with the pressure release valve open; after a steady flow of steam is obtained through the valve, continuing to purge for 3 minutes to remove all air, closing the valve, bringing the autoclave to 80 psi (552 kPa) and at 324°F ( 162°C) in a total time of 1 hour, maintaining the autoclave at 80 ⁇ 5 psi (552 ⁇ 50 kPa) at 324 ⁇ 4°F ( 162 ⁇ 2°C) for 5 hour, allowing sufficient cooling to lower the autoclave to 20 to 30 psi ( 138 to 207 kPa) with the release valve closed, and then carefully opening the relief valve to reduce the autoclave to atmospheric pressure in a total time between 30 and 60 minutes.
• testing protocol with an autoclave chamber is known among the persons with ordinary skill in the relevant art.
• the testing specimens were collected, observed for hydration degree, and photographed immediately.
• the degree of hydration was rated from 1 - 4 as follows:
• hydration degrees of refractory brick specimens were rated lower when SiC content was increased over the tested firing temperatures and firing durations. For instance, at the firing temperature of 1 ,300 °C and a firing interval of 60 minutes, hydration degree was 3.4 in the absence of SiC in a refractory brick, and hydration degree consistently decreased when SiC content increased from 1 - 15 % (i.e., hydration degree decreased from 3.4 down to 3.3, 2, 1 , 1 and 1 as SiC content was elevated from 0, 1 , 3, 5, 10, and 15%, respectively.)
• Incorporation of a predetermined amount of SiC into a refractory article or brick having a composition according to an embodiment of the present disclosure can provide, facilitate, effectuate and/or improve anti-hydration properties as indicated by a numerical reduction in hydration rating score, and/or as indicated in another manner, for instance, by way of representative photographs from collected specimens.
• Thermal conductivity property evaluation Effect of temperature and varying composition
• Thermal conductivity refers to the property of a material to conduct heat, and can predict the rate of energy loss through the material. It is desirable to choose a refractory brick having minimal, low, or substantially low thermal conductivity in order to minimize or prevent heat transmission or energy loss and achieve better thermal insulation property.
• Thermal conductivity was investigated by placing thermocouples and positioning test specimens in a thermal conductivity tester based on a conventional wire method (e.g., using a thermal conductivity tester with a power supply unit, a controller and a hood type furnace).
• refractory brick compositions namely refractory brick compositions (A), (B), and (C) were prepared to a standard shape having 230 x 1 15 x 64 mm in size.
• refractory brick compositions (A) and (B) are enumerated as follows:
• Refractory brick composition (A) included approximately 60% Olivine, 27% Magnesia, 10% Spinel, and 3% SiC by weight.
• Refractory brick composition (B) included approximately 80% Magnesia, 20% Spinel by weight.
• refractory Brick No. 1 was placed on an alumina frame, followed by an adjustment of the hot wire and thermocouple position in order to insert or embed them into the prepared mortice. Said mortice was filled by tabular alumina slurry or fused spinel slurry to cover the mortices. Then refractory Brick No. 2 was placed over Brick No. 1 and a reference thermocouple was placed in a mortice formed, followed by filling the mortice in a similar manner to the refractory Brick No. 1 . Finally, Brick No. 3 was laid down on Brick No. 2. Then the specimens were loaded into a chamber corresponding to a thermal conductivity tester.
• Input data and/or parameters input into the thermal conductivity tester were determined, selected or specified as follows:
• FIG. 3 illustrates a correlation between thermal conductivity values and temperatures varied in the range of 200- 1 ,200 °C from refractory bricks having a composition according to embodiments of the present disclosure.
• the thermal conductivity of refractory brick composition (A) slightly decreased with increasing of temperature in the range of 200 - 400 °C, while thermal conductivity of refractory brick A remained relatively constant at 2.00 W/mK in the range of 450 - 1200 °C.
• Thermal conductivity values of refractory brick composition (B) greatly decreased when the temperature increased over the testing temperatures. In other words, the thermal conductivity of refractory brick composition (A) was insensitive or essentially insensitive to the temperatures used during firing unlike brick compositions (B).
• thermal conductivity values of refractory brick composition (A) are significantly, dramatically, or drastically and surprisingly lower than that of conventional refractory brick compositions (B).
• thermo conductivity of refractory brick provided by the present disclosure at 3% of SiC (composition (A)) is significantly lower than that of Magnesia spinel brick (composition B).
• composition (A) is significantly lower than that of Magnesia spinel brick (composition B).
• refractory bricks prepared by several embodiments in accordance with the present disclosure have low thermal conductivity with insensitivity toward higher operating temperatures, and/or have high thermal insulation properties. That is, the refractory bricks provided or produced in accordance with embodiments of the present disclosure can have wider temperature ranges for applications with better, enhanced, improved, or superior insulation properties (e.g., compared to conventional refractory brick compositions), resulting in less energy loss, as compared to the conventional refractory bricks.
• Example Three Experiments in Example Three were performed to determine permeability of a refractory brick having a composition in accordance with present disclosure. Permeability reflects the chemical infiltration resistance property of a material. It is desirable to choose a refractory brick having low permeability for durability and associated operating costs upon its application or usage.
• Refractory brick specimens according to a representative embodiment in the present disclosure comprised or were formed of olivine at 60%, magnesia 27 %, spinel 10% and SiC at 3% by weight. Briefly, refractory brick specimens were prepared in the size of 51 x 51 x 51 ⁇ 1 mm by a cutting machine and were identified on particular side surface as follows:
• A denotes as a compressive face
• B denotes as a side face
• C denotes hot/cold face
• P reduced pressure
• an average permeability of the refractory bricks having olivine at 60%, magnesia 27 %, spinel 10% and SiC at 3% by weight is 5.27 cD.
• an average permeability of conventional refractory bricks without SiC incorporated therein is 20-30 cD, as will be readily understood by individuals having ordinary skill in the relevant art. Therefore, refractory brick compositions according to the present disclosure can have substantially or dramatically and surprisingly lower value of permeability by 73.7-82.4%, as compared to conventional refractory brick compositions.
• Refractory brick compositions according to embodiments of the present disclosure demonstrate a significant reduction in air permeability. Hence, it indicates that a refractory brick composition according to embodiments of the present disclosure possesses a significantly or greatly enhanced, improved, or superior chemical infiltration resistance by at least 73.7 %, as compared to conventional refractory bricks.
• Example 4 Experiments in example 4 were carried out to inspect the microstructure of a refractory brick having a composition in accordance with the present disclosure.
• Scanning Electron Micrograph (SEM) is utilized to scan a refractory brick sample with focused beams of electrons to obtain the refractory brick sample's topography, and the constituents in the composition were determined by an Energy Dispersive X-ray (EDX) analysis.
• EDX Energy Dispersive X-ray
• a refractory brick sample in Example 4 comprises or is made of 40-90% of olivine, 5-35% of spinel, 1 -15% of SiC, and MgO at the percent weight to make up to total 100%. Details of the sample preparation and procedure are explained below.
• Sample casting step The refractory brick was prepared by a sample cutting machine to 2.0 x 2.0 x 2.0 cm in size, then dried at 1 10 °C. Resin and hardener were mixed together at a mixing ratio 5: 1 for I minute at 18 gram per sample. Releasing agent was applied to a mold then said resin was poured into the mold under vacuum for 7- 10 minutes and allowed to sit or be left for 8 hours and then demolded.
• Sample cutting The demolded sample was cut at least 1.5 mm in depth with a normal cutting speed of 375 rpm.
• Sample polishing At least three samples were polished by a grinder/polisher (Model
• SEM and EDX peak analysis indicated the presence of SiC on magnesia and magnesia silicate in a refractory brick composition according to embodiments of the present disclosure.
• Example five Experiments in Example five were performed to obtain an appropriate SiC particle size that results in the most desirable property of a refractory brick having a composition in accordance with present disclosure.
• Refractory brick specimens in example five were prepared by having an identical amount of SiC (i.e. at SiC of 5% by weight) and varying SiC particle size from fine to coarse grain (i.e. fine grain at the particle size range of 10 ⁇ - 5 mm versus coarse grain at the particle size larger than 5 millimeter).
• Two refractory brick properties namely modulus of rupture (MOR) and cold crushing strength (CCS) were measured by a standard technique known in the art.
• Table 3 depicting the results of experiments in example 5 demonstrates that, comparing at an identical SiC amount, both refractory brick properties; more specifically, modulus of rupture (MOR) and cold crushing strength (CCS) of a refractory brick with fine SiC particle (i.e. particle size of 10 ⁇ - 5 mm) having a composition in accordance with the present disclosure are substantially higher than those of a refractory brick with coarse SiC particle (i.e. particle size of > 5 mm). More particularly, decreasing the particle size of SiC from a coarse to fine range can significantly or very significantly increase MOR and CCS of the refractory brick by approximately 4 fold.
• MOR modulus of rupture
• CCS cold crushing strength

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• 2015
  • 2015-12-29 EP EP15910980.0A patent/EP3224221A4/de not_active Withdrawn
  • 2015-12-29 CN CN201580030636.3A patent/CN107207355A/zh active Pending
  • 2015-12-29 BR BR112017001900A patent/BR112017001900A2/pt not_active Application Discontinuation
  • 2015-12-29 WO PCT/TH2015/000098 patent/WO2017116313A1/en active Application Filing

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