Carbon-free Al_(2)O_(3)-MgO dense bricks were produced by the pressing method,using tabular alumina,white fused alumina,alumina micro-powder as main raw materials,and inorganic powder as the binder.The comprehensive p...Carbon-free Al_(2)O_(3)-MgO dense bricks were produced by the pressing method,using tabular alumina,white fused alumina,alumina micro-powder as main raw materials,and inorganic powder as the binder.The comprehensive properties and performance in steel ladle side wall were made a comparison between Al_(2)O_(3)-MgO dense bricks and precast blocks.The results show that Al_(2)O_(3)-MgO dense bricks exhibit high dense structure and strength,as well as superior thermal shock resistance and better penetration and corrosion resistance to slag than precast blocks.While replacing precast blocks with dense bricks in 250 t steel ladle side wall in some domestic steel mills,the thickness of the metamorphic layer from slag penetration and the corrosion rate decrease evidently.The damage of dense bricks during service is mainly caused by the corrosion from molten steel and slag,and the structure spalling of the metamorphic layer also plays an important role.展开更多
Dense corundum-mullite brick for blast furnace ceramic pad was prepared using white fused corundum and tabular corundum as aggregates,andalusite fine powder,sillimanite fine powder,zircon sand powder and Guangxi soil ...Dense corundum-mullite brick for blast furnace ceramic pad was prepared using white fused corundum and tabular corundum as aggregates,andalusite fine powder,sillimanite fine powder,zircon sand powder and Guangxi soil as the matrix,and phosphate as the binder,introducing different amounts ofα-alumina micropowder,tabular corundum fine powder and fused corundum powder.The properties of the prepared brick were studied.The results show that,the brick with 10 mass%of tabular corundum fine powder fired at 1560℃for 3 h in a tunnel kiln has the bulk density of 3.08 g·cm^(-3),the apparent porosity of 13.2%,the cold compressive strength of 178 MPa,the molten iron corrosion rate of 0.6%,the slag corrosion rate of 6.4%,the alkali resistance strength decreasing rate of 7.5%,and the thermal shock resistance of 32 cycles,which is both dense and of good thermal shock resistance.The slag resistance simulation test was performed,which proved that the prepared corundum-mullite brick is better than those currently supplied in the market.展开更多
The paper aims at investigating whether corundum bricks can be used for the bottom, of the direct reduction furnace of high phosphorus oolitic hematite. The reducing materials including high phosphorus oolitic hemati...The paper aims at investigating whether corundum bricks can be used for the bottom, of the direct reduction furnace of high phosphorus oolitic hematite. The reducing materials including high phosphorus oolitic hematite, bitumite, Ca（OH） 2 and Na2CO3 at a mass ratio of 1：0. 15：0. 15：0. 03 were mixed and pressed into carbon containing cylindrical specimens with the size of Ф15 mm × 20 mm. The specimens were placed on the corundum bricks and reduced in a high temperature tube furnace at 1 200 ℃ for 40, 60, 80, 140 and 220 min, respective- ly. The corrosion and penetration resistance of corundum. bricks to high phosphorus oolitic hematite reducing materials were analyzed with XRD, SEM and EDS. It shows that the reducing slag formed in the reduction process corrodes the surface of corundum bricks to form a product layer of anorthite and hercynite, retarding the further corrosion of the reducing slag; the reducing slag which has penetrated into the interior of the brick goes through the gaps between the particles and generates anorthite and hercynite, filling the gaps and hindering the reducing slag penetration.展开更多
The paper presents a new method to synthesize β-Sialon bonded corundum brick (β-SBCB) from Al-Si alloy directly and easily under 1430℃ , the volume expansion of reaction between Al powder and Nitrogen can help to e...The paper presents a new method to synthesize β-Sialon bonded corundum brick (β-SBCB) from Al-Si alloy directly and easily under 1430℃ , the volume expansion of reaction between Al powder and Nitrogen can help to establish the fast diffusion channel in Al-Si alloy; the suitable crystal seed of Si3N4 is helpful to the fast synthesis of β-Sialon.展开更多
The paper describes the ries with high thermal shock development of brick seresistance and low creep rate for hot blast stove, including research target and research plan on the basis of analysis on how to enhance the...The paper describes the ries with high thermal shock development of brick seresistance and low creep rate for hot blast stove, including research target and research plan on the basis of analysis on how to enhance the thermal shock resistance and to lower creep rate of the bricks. Efforts have been made on the selection of starting materials such as corundum, mullite, andalusite and sillimanite etc., together with some measures taken on multi-grade formulation, homogenizing of the matrix of bricks and addition of some special additives. The results indicated that the bricks were with characteristics such as higher thermal shock resistance of 〉 30 cycles under quenching in water from 1000℃, and creep rate of 0. 2 under 1400℃ for 20 -50hrs with load of 0.2 MPa. Now a series of products of this kind have been developed and produced. The application of the products in Wuhan Iron and Steel Co. showed very prospective results. Now most of domestic large sized blast furnaces say ≥- 1000m^3, including those of Baoshan Iron and Steel Co. , have selected the series products made by Gongyi No. 5 Refractories Head Factory（GYWN） for their hot blast stoves.展开更多
The manufacture of clean steel needs high performance carbon-free bricks for ladle lining.Based on long term application experiences of the prefab Al_(2)O_(3)-MgO blocks,unburnt Al_(2)O_(3)-MgO brick has been develope...The manufacture of clean steel needs high performance carbon-free bricks for ladle lining.Based on long term application experiences of the prefab Al_(2)O_(3)-MgO blocks,unburnt Al_(2)O_(3)-MgO brick has been developed by pressing a mix of alumina,spinel and magnesia as major raw materials and Al_(2)O_(3)-MgO gel powder as binder.In addition to low open porosity and high strength,the unburnt Al_(2)O_(3)-MgO brick shows superior corrosion resistance and thermal shock resistance to the prefab block.Field trials in a 300t steel ladle have indicated the residual lining of unburnt Al_(2)O_(3)-MgO bricks showed smooth surface without large spalling and seldom steel infiltration,consequently longer service life than the prefab blocks.The reliable,unburnt Al_(2)O_(3)-MgO bricks have more advantages of high efficiency,energy-saving and eco-friendly production.It will be one of the best options for ladle lining in the manufacture of high-purity steel.展开更多
为了满足生产低碳钢和超低碳钢的技术要求,以棕刚玉、板状刚玉、电熔镁铝尖晶石粉为原料,电熔镁砂粉和α-氧化铝微粉为添加剂,络合镁铝溶胶为结合剂,研制出了机压成型免烧刚玉-尖晶石无碳砖,并进行了实验。试验结果表明:当电熔镁砂粉和...为了满足生产低碳钢和超低碳钢的技术要求,以棕刚玉、板状刚玉、电熔镁铝尖晶石粉为原料,电熔镁砂粉和α-氧化铝微粉为添加剂,络合镁铝溶胶为结合剂,研制出了机压成型免烧刚玉-尖晶石无碳砖,并进行了实验。试验结果表明:当电熔镁砂粉和α-氧化铝微粉加入量分别为3%和8%时,试验砖的性能最佳。该砖在太钢90 t LF钢包熔池及包底部位使用,其寿命达到105炉。展开更多
文摘Carbon-free Al_(2)O_(3)-MgO dense bricks were produced by the pressing method,using tabular alumina,white fused alumina,alumina micro-powder as main raw materials,and inorganic powder as the binder.The comprehensive properties and performance in steel ladle side wall were made a comparison between Al_(2)O_(3)-MgO dense bricks and precast blocks.The results show that Al_(2)O_(3)-MgO dense bricks exhibit high dense structure and strength,as well as superior thermal shock resistance and better penetration and corrosion resistance to slag than precast blocks.While replacing precast blocks with dense bricks in 250 t steel ladle side wall in some domestic steel mills,the thickness of the metamorphic layer from slag penetration and the corrosion rate decrease evidently.The damage of dense bricks during service is mainly caused by the corrosion from molten steel and slag,and the structure spalling of the metamorphic layer also plays an important role.
文摘Dense corundum-mullite brick for blast furnace ceramic pad was prepared using white fused corundum and tabular corundum as aggregates,andalusite fine powder,sillimanite fine powder,zircon sand powder and Guangxi soil as the matrix,and phosphate as the binder,introducing different amounts ofα-alumina micropowder,tabular corundum fine powder and fused corundum powder.The properties of the prepared brick were studied.The results show that,the brick with 10 mass%of tabular corundum fine powder fired at 1560℃for 3 h in a tunnel kiln has the bulk density of 3.08 g·cm^(-3),the apparent porosity of 13.2%,the cold compressive strength of 178 MPa,the molten iron corrosion rate of 0.6%,the slag corrosion rate of 6.4%,the alkali resistance strength decreasing rate of 7.5%,and the thermal shock resistance of 32 cycles,which is both dense and of good thermal shock resistance.The slag resistance simulation test was performed,which proved that the prepared corundum-mullite brick is better than those currently supplied in the market.
文摘The paper aims at investigating whether corundum bricks can be used for the bottom, of the direct reduction furnace of high phosphorus oolitic hematite. The reducing materials including high phosphorus oolitic hematite, bitumite, Ca（OH） 2 and Na2CO3 at a mass ratio of 1：0. 15：0. 15：0. 03 were mixed and pressed into carbon containing cylindrical specimens with the size of Ф15 mm × 20 mm. The specimens were placed on the corundum bricks and reduced in a high temperature tube furnace at 1 200 ℃ for 40, 60, 80, 140 and 220 min, respective- ly. The corrosion and penetration resistance of corundum. bricks to high phosphorus oolitic hematite reducing materials were analyzed with XRD, SEM and EDS. It shows that the reducing slag formed in the reduction process corrodes the surface of corundum bricks to form a product layer of anorthite and hercynite, retarding the further corrosion of the reducing slag; the reducing slag which has penetrated into the interior of the brick goes through the gaps between the particles and generates anorthite and hercynite, filling the gaps and hindering the reducing slag penetration.
文摘The paper presents a new method to synthesize β-Sialon bonded corundum brick (β-SBCB) from Al-Si alloy directly and easily under 1430℃ , the volume expansion of reaction between Al powder and Nitrogen can help to establish the fast diffusion channel in Al-Si alloy; the suitable crystal seed of Si3N4 is helpful to the fast synthesis of β-Sialon.
基金The paper was presented at the Unitecr’05,which was held in Orlando. USA on Nov.8~11,2005
文摘The paper describes the ries with high thermal shock development of brick seresistance and low creep rate for hot blast stove, including research target and research plan on the basis of analysis on how to enhance the thermal shock resistance and to lower creep rate of the bricks. Efforts have been made on the selection of starting materials such as corundum, mullite, andalusite and sillimanite etc., together with some measures taken on multi-grade formulation, homogenizing of the matrix of bricks and addition of some special additives. The results indicated that the bricks were with characteristics such as higher thermal shock resistance of 〉 30 cycles under quenching in water from 1000℃, and creep rate of 0. 2 under 1400℃ for 20 -50hrs with load of 0.2 MPa. Now a series of products of this kind have been developed and produced. The application of the products in Wuhan Iron and Steel Co. showed very prospective results. Now most of domestic large sized blast furnaces say ≥- 1000m^3, including those of Baoshan Iron and Steel Co. , have selected the series products made by Gongyi No. 5 Refractories Head Factory（GYWN） for their hot blast stoves.
文摘The manufacture of clean steel needs high performance carbon-free bricks for ladle lining.Based on long term application experiences of the prefab Al_(2)O_(3)-MgO blocks,unburnt Al_(2)O_(3)-MgO brick has been developed by pressing a mix of alumina,spinel and magnesia as major raw materials and Al_(2)O_(3)-MgO gel powder as binder.In addition to low open porosity and high strength,the unburnt Al_(2)O_(3)-MgO brick shows superior corrosion resistance and thermal shock resistance to the prefab block.Field trials in a 300t steel ladle have indicated the residual lining of unburnt Al_(2)O_(3)-MgO bricks showed smooth surface without large spalling and seldom steel infiltration,consequently longer service life than the prefab blocks.The reliable,unburnt Al_(2)O_(3)-MgO bricks have more advantages of high efficiency,energy-saving and eco-friendly production.It will be one of the best options for ladle lining in the manufacture of high-purity steel.
文摘为了满足生产低碳钢和超低碳钢的技术要求,以棕刚玉、板状刚玉、电熔镁铝尖晶石粉为原料,电熔镁砂粉和α-氧化铝微粉为添加剂,络合镁铝溶胶为结合剂,研制出了机压成型免烧刚玉-尖晶石无碳砖,并进行了实验。试验结果表明:当电熔镁砂粉和α-氧化铝微粉加入量分别为3%和8%时,试验砖的性能最佳。该砖在太钢90 t LF钢包熔池及包底部位使用,其寿命达到105炉。
