The microstructure and slag erosion fractal dimension of reaction interface of β-Sialon-Al2O3 brick used in 300 Mt iron ladle of Baosteel have been studied by SEM and XRD. The results indicated that β-Sialon-Al2O3 b...The microstructure and slag erosion fractal dimension of reaction interface of β-Sialon-Al2O3 brick used in 300 Mt iron ladle of Baosteel have been studied by SEM and XRD. The results indicated that β-Sialon-Al2O3 brick exhibited excellent slag resistance. The main wear mechanism of β-Sialon-Al2O3 brick is mainly from the spalling caused by thermal mechanical stress and attacked by slag secondly.展开更多
The state-of-art of magnesia-chrome refractories from direct-bonded magnesia chrome brick to fused-grain rebounded magnesia chrome brick for P-S converter is dis-cribed. The Cr2O3 content of the brick is continually i...The state-of-art of magnesia-chrome refractories from direct-bonded magnesia chrome brick to fused-grain rebounded magnesia chrome brick for P-S converter is dis-cribed. The Cr2O3 content of the brick is continually increased with the reduction of the impurity content of brick , the pre-synthetic raw material it applied and the operating condition of convener is optimized so that the service life of convener is largely enhanced.展开更多
This paper describes developments of high quality magnesite-chrome bricks used for secondary steelmaking furnaces,mainly including direct-bond-ed magnesite-chrome brick,fully synthesized(co-clinker) magnesite-chrome ...This paper describes developments of high quality magnesite-chrome bricks used for secondary steelmaking furnaces,mainly including direct-bond-ed magnesite-chrome brick,fully synthesized(co-clinker) magnesite-chrome brick,semi-rebonded magnesite-chrome brick and fused grain rebonded magnesite-chroe brick,Investigations have also been conducted on the effects of various chromites on the properties of the direct bonded magnesite-chrome brick,effects of different sesquioxides (CrO3,Al3O3,Fe2O3) on the properties of the fully synthe-sized(co-clinker) magnesite-hrome brick and ef-fects of ZrO2,Cr-Fe alloy,ultra-fine powders on the properties of the fused grain rebonded brick and the semi-rebonded magnesite-chrome brick ,Applica-tions of the bricks in various secondary steelmaking furnaces have been briefly introduced as well.展开更多
This paper reviews the history of development and production of silica bricks at Luoyang Refrac-tories(Group) Co.,Ltd,(Former Luoyang Refrac-tories Factory). Through the improvement and in-troducing technology from a...This paper reviews the history of development and production of silica bricks at Luoyang Refrac-tories(Group) Co.,Ltd,(Former Luoyang Refrac-tories Factory). Through the improvement and in-troducing technology from abroad the company's management and quality standard on silica bricks production has reached a higher level.The physical and chemical specifications,as well as the appear-ance of silica bricks for coke ovens,hot blast stoves and glass kilns have reached the advanced interna-tional level.Now the company has become producing base and main exporting base various kinds of silica bricks in China.展开更多
The paper describes the reaction between car-bon-containing refractories,magnesia-chrome re-fractories and matte,converter slag.The results show that carbon-containing refractories have good resistance to matte and co...The paper describes the reaction between car-bon-containing refractories,magnesia-chrome re-fractories and matte,converter slag.The results show that carbon-containing refractories have good resistance to matte and converter slag in nitrogen at-mosphere,The practical results are unsuitable for converter,high performace magnesia chrome re-fractories are promising materials.Newly devel-oped high quality direct bonding magnesia chrome,rebonded co-clinker magnesia chrome,semi-rebonded magnesia chrome,fused cast magnesia chrome used in smelting furances are introduced briefly.展开更多
As coke oven becoming larger,silica brick for coke oven is required to be of high uqality,Luoyang Refractories(Grop)Co.Ltd.(LRCO) has re-searched the mineralizer which contains Ca^2+,R^+,Al^3+,F^-,emphatically and pro...As coke oven becoming larger,silica brick for coke oven is required to be of high uqality,Luoyang Refractories(Grop)Co.Ltd.(LRCO) has re-searched the mineralizer which contains Ca^2+,R^+,Al^3+,F^-,emphatically and proposed the principle of composite mineralizer basd on the properties of raw materials used .High performance silia brick which is characterized by low thermal expansion rate,good high temperature properties,residual quartz<0.5%,true density 2.31,and high bulk density silica brick for carbonization room with apparent porosity 13% ,bulk density l.96 g/cm^3 have been developed and produced successfully by LR-CO.The quality of the bricks has reached the inter-national advenced level.展开更多
The application results of Semi-rebonded Magnesite-Chrome bricks at RH lower vessl of the NKK Corporation Keihin Works have been analysed.The results indicate that the main reasons that cause the damage of the refract...The application results of Semi-rebonded Magnesite-Chrome bricks at RH lower vessl of the NKK Corporation Keihin Works have been analysed.The results indicate that the main reasons that cause the damage of the refractory bricks include chemical at-tack of slag to the Semi-rebonded Magnesite-Chrome bricks;penetration of molten steel and slagn into the bricks;and thermal spalling due to teperature fluctuation during steel making operation. The re-sulits of multiple effection of these factors lead to alternative action of erosion(chemicl attack and penetration) and spalling (thermal spalling and structure peeling) resulting in the damage of the brick,In order to improve the performance of the bricks,it is necessary to promote the resistance to ero-sion and thermal shock resistance as well as to keep the aurate dimensions of the brick .The measures to improve the resistance to erosion of magnesite-chrome bricks taken by the researchers mainly in-clude:lowering the contents of impurities in the bricks (mainly including SiO2,CaO,and next Fe2O3 and Al2O3);promoting the extent of direct bond of the brick;forming a large amount of magnesia-chrome composite spinel well-distributed in the bricks through adding a large amount of synthe-sized materials ;enhancing the resistance to erosion by adding a little amount of high-effective addi-tives,Improvement of thermal shock resistance of the bricks is mainly through introducing some addi-tive to make a certain amount of micro-cracks occur-ing in the brick so as to obtain the effect of increase toughness or through formation of second high tem-perture solid phse in the brick by adopting addi-tive,In ddition,it is needed to improve the quality of the brick appearance and ensure accurate dimen-sions of the brick ,The purpose of this paper is to describe the further improvement of the service life of refactory brick by the measures taken on the basis of the nalysis results to the used bricks.展开更多
Appliction of MgO0-Cr2O3 brick composed of MgO>72%,Cr2O3>14.8%-168.69%,with porosity 13%-14%,compressive strength 33.0-43.8 MPa, flexure strength 11.9-16.5 MPa and refractoriness under load ≥1750℃ in an assem...Appliction of MgO0-Cr2O3 brick composed of MgO>72%,Cr2O3>14.8%-168.69%,with porosity 13%-14%,compressive strength 33.0-43.8 MPa, flexure strength 11.9-16.5 MPa and refractoriness under load ≥1750℃ in an assemble snorkel of 300t RH furnace in Baoskhan Iron & Steel Company (Baosteel)Showed good results of average service life of 106.6 heats,maximum 119 heats.Petrologi-cal analysis and visual examination were also done to the residual brick to investigate the wear mecha-nism.展开更多
Low-creep rate brick H1SS and H2SS have been studied in Luoyang Refractories Co., Ltd.on the basis of former results using different grade synthetic mullite and natural sillimanite concen-trate,Good microstructure and...Low-creep rate brick H1SS and H2SS have been studied in Luoyang Refractories Co., Ltd.on the basis of former results using different grade synthetic mullite and natural sillimanite concen-trate,Good microstructure and high temperature properties can be obtained by using high quality raw material and reasonable proportioning and technology.The creep values of H1SS and H2SS are less han 0.5% at 1400℃ and 0.45％ at 1350℃。展开更多
Using Al2O3-MgO castable in large ladle can avoid containation of molten steel from carbon-containing refractories and increas ladle servic life remarkably,The addition of magnesia and fine powder,the effect of grain ...Using Al2O3-MgO castable in large ladle can avoid containation of molten steel from carbon-containing refractories and increas ladle servic life remarkably,The addition of magnesia and fine powder,the effect of grain size on the proper-ties of the castable,especially linear change and structure spalling have been studied,Castable pro-dued for large ladle with small weare rate has got good applicatio result.展开更多
The paper describes the process of producing high quality magnesite-chrome bricks for VOD re-fining furnace,The service life reaches 14 heats,average life 12 heats.The studies show that the wear of the magnesity-chrom...The paper describes the process of producing high quality magnesite-chrome bricks for VOD re-fining furnace,The service life reaches 14 heats,average life 12 heats.The studies show that the wear of the magnesity-chrome bricks is mainly due to chemical corrosion,thermal spalling induced by thermal shock and the corrosion aroused from accumulation of molten materials in transition zone.展开更多
文摘The microstructure and slag erosion fractal dimension of reaction interface of β-Sialon-Al2O3 brick used in 300 Mt iron ladle of Baosteel have been studied by SEM and XRD. The results indicated that β-Sialon-Al2O3 brick exhibited excellent slag resistance. The main wear mechanism of β-Sialon-Al2O3 brick is mainly from the spalling caused by thermal mechanical stress and attacked by slag secondly.
文摘The state-of-art of magnesia-chrome refractories from direct-bonded magnesia chrome brick to fused-grain rebounded magnesia chrome brick for P-S converter is dis-cribed. The Cr2O3 content of the brick is continually increased with the reduction of the impurity content of brick , the pre-synthetic raw material it applied and the operating condition of convener is optimized so that the service life of convener is largely enhanced.
文摘This paper describes developments of high quality magnesite-chrome bricks used for secondary steelmaking furnaces,mainly including direct-bond-ed magnesite-chrome brick,fully synthesized(co-clinker) magnesite-chrome brick,semi-rebonded magnesite-chrome brick and fused grain rebonded magnesite-chroe brick,Investigations have also been conducted on the effects of various chromites on the properties of the direct bonded magnesite-chrome brick,effects of different sesquioxides (CrO3,Al3O3,Fe2O3) on the properties of the fully synthe-sized(co-clinker) magnesite-hrome brick and ef-fects of ZrO2,Cr-Fe alloy,ultra-fine powders on the properties of the fused grain rebonded brick and the semi-rebonded magnesite-chrome brick ,Applica-tions of the bricks in various secondary steelmaking furnaces have been briefly introduced as well.
文摘This paper reviews the history of development and production of silica bricks at Luoyang Refrac-tories(Group) Co.,Ltd,(Former Luoyang Refrac-tories Factory). Through the improvement and in-troducing technology from abroad the company's management and quality standard on silica bricks production has reached a higher level.The physical and chemical specifications,as well as the appear-ance of silica bricks for coke ovens,hot blast stoves and glass kilns have reached the advanced interna-tional level.Now the company has become producing base and main exporting base various kinds of silica bricks in China.
文摘The paper describes the reaction between car-bon-containing refractories,magnesia-chrome re-fractories and matte,converter slag.The results show that carbon-containing refractories have good resistance to matte and converter slag in nitrogen at-mosphere,The practical results are unsuitable for converter,high performace magnesia chrome re-fractories are promising materials.Newly devel-oped high quality direct bonding magnesia chrome,rebonded co-clinker magnesia chrome,semi-rebonded magnesia chrome,fused cast magnesia chrome used in smelting furances are introduced briefly.
文摘As coke oven becoming larger,silica brick for coke oven is required to be of high uqality,Luoyang Refractories(Grop)Co.Ltd.(LRCO) has re-searched the mineralizer which contains Ca^2+,R^+,Al^3+,F^-,emphatically and proposed the principle of composite mineralizer basd on the properties of raw materials used .High performance silia brick which is characterized by low thermal expansion rate,good high temperature properties,residual quartz<0.5%,true density 2.31,and high bulk density silica brick for carbonization room with apparent porosity 13% ,bulk density l.96 g/cm^3 have been developed and produced successfully by LR-CO.The quality of the bricks has reached the inter-national advenced level.
文摘The application results of Semi-rebonded Magnesite-Chrome bricks at RH lower vessl of the NKK Corporation Keihin Works have been analysed.The results indicate that the main reasons that cause the damage of the refractory bricks include chemical at-tack of slag to the Semi-rebonded Magnesite-Chrome bricks;penetration of molten steel and slagn into the bricks;and thermal spalling due to teperature fluctuation during steel making operation. The re-sulits of multiple effection of these factors lead to alternative action of erosion(chemicl attack and penetration) and spalling (thermal spalling and structure peeling) resulting in the damage of the brick,In order to improve the performance of the bricks,it is necessary to promote the resistance to ero-sion and thermal shock resistance as well as to keep the aurate dimensions of the brick .The measures to improve the resistance to erosion of magnesite-chrome bricks taken by the researchers mainly in-clude:lowering the contents of impurities in the bricks (mainly including SiO2,CaO,and next Fe2O3 and Al2O3);promoting the extent of direct bond of the brick;forming a large amount of magnesia-chrome composite spinel well-distributed in the bricks through adding a large amount of synthe-sized materials ;enhancing the resistance to erosion by adding a little amount of high-effective addi-tives,Improvement of thermal shock resistance of the bricks is mainly through introducing some addi-tive to make a certain amount of micro-cracks occur-ing in the brick so as to obtain the effect of increase toughness or through formation of second high tem-perture solid phse in the brick by adopting addi-tive,In ddition,it is needed to improve the quality of the brick appearance and ensure accurate dimen-sions of the brick ,The purpose of this paper is to describe the further improvement of the service life of refactory brick by the measures taken on the basis of the nalysis results to the used bricks.
文摘Appliction of MgO0-Cr2O3 brick composed of MgO>72%,Cr2O3>14.8%-168.69%,with porosity 13%-14%,compressive strength 33.0-43.8 MPa, flexure strength 11.9-16.5 MPa and refractoriness under load ≥1750℃ in an assemble snorkel of 300t RH furnace in Baoskhan Iron & Steel Company (Baosteel)Showed good results of average service life of 106.6 heats,maximum 119 heats.Petrologi-cal analysis and visual examination were also done to the residual brick to investigate the wear mecha-nism.
文摘Low-creep rate brick H1SS and H2SS have been studied in Luoyang Refractories Co., Ltd.on the basis of former results using different grade synthetic mullite and natural sillimanite concen-trate,Good microstructure and high temperature properties can be obtained by using high quality raw material and reasonable proportioning and technology.The creep values of H1SS and H2SS are less han 0.5% at 1400℃ and 0.45％ at 1350℃。
文摘Using Al2O3-MgO castable in large ladle can avoid containation of molten steel from carbon-containing refractories and increas ladle servic life remarkably,The addition of magnesia and fine powder,the effect of grain size on the proper-ties of the castable,especially linear change and structure spalling have been studied,Castable pro-dued for large ladle with small weare rate has got good applicatio result.
文摘The paper describes the process of producing high quality magnesite-chrome bricks for VOD re-fining furnace,The service life reaches 14 heats,average life 12 heats.The studies show that the wear of the magnesity-chrome bricks is mainly due to chemical corrosion,thermal spalling induced by thermal shock and the corrosion aroused from accumulation of molten materials in transition zone.
