A mathematical model which describes the fluid flow in a gas stirred original ladle and CAS OB ladle was introduced. The fluid field analysis was obtained through mathematical simulation. In order to decrease the lad...A mathematical model which describes the fluid flow in a gas stirred original ladle and CAS OB ladle was introduced. The fluid field analysis was obtained through mathematical simulation. In order to decrease the ladle refractory wearing and increase the heating speed of liquid steel, some measures should be adopted. The result shows that the flow fields in CAS OB ladle and original ladle are different. With a fixed gas flow rate, the flow field is related to the plug position and the snorkel depth. When the nozzle is located at 0 45 r , where r is the radius of ladle bottom, the fluid field predicted by water modeling is quite satisfactory for improving the quality of liquid steel.展开更多
Phosphate coatings are partially dissolved in the cathodic area during the cathode-electrophoretic painting processes causing the result that the coatings adhesion, corrosion protection, alkaline resistance are decrea...Phosphate coatings are partially dissolved in the cathodic area during the cathode-electrophoretic painting processes causing the result that the coatings adhesion, corrosion protection, alkaline resistance are decreased. Furthermore, the service life of the coated production will be shortened. The addition of Ni2+, Mn2+ to the phosphating bath to improve the corrosion stability, alkaline resistance, as well as the adhesion of coating layers is studied in the article. These heavy metals do not only catalyse the surface reactions but generate a more corrosion resistant surface. We perfected the trecation phosphate solution by reducing the sludge, accelerating the phosphating reactions, improving corrosion protection and alkaline resistance. More even and finer grain structures, excellent corrosion resistance were obtained compared to the traditional phosphating technique.展开更多
The effects of several processing parame-ters on size and distributions of mullite powders were studied in wet grinding with an attrition mill.The results show that there is an optimum initial slurry density,and also ...The effects of several processing parame-ters on size and distributions of mullite powders were studied in wet grinding with an attrition mill.The results show that there is an optimum initial slurry density,and also it has little rela-tionship with the media charge ratio.The size distributions of processed mullite are dependent on the grinding time and indepentdent of initial pulp density,Under given conditions,the larger the media charge ration is ,the finer the ground particle size will be.展开更多
The structure and oxidation behaviors of pitch carbon,resin carbon and their mixture re-sultant carbon have been investigated.The results indicate that the pitch carbon has relative higher true specific gravity,well d...The structure and oxidation behaviors of pitch carbon,resin carbon and their mixture re-sultant carbon have been investigated.The results indicate that the pitch carbon has relative higher true specific gravity,well developed crystalline and better oxidation resistance than resin carbon,With 20%-35% resin added to pitch,the structure of the resultant carbon can be modified and oxidation resistance will be improved significantly.展开更多
The structure and oxidation resistance of five kinds of phenol formaldehyde resin-based carbons have been studied.The effects of heating treatment conditions(HTC) of the resins on the crystal structure and microstruct...The structure and oxidation resistance of five kinds of phenol formaldehyde resin-based carbons have been studied.The effects of heating treatment conditions(HTC) of the resins on the crystal structure and microstructure have been investigated,and the relationships between structure and oxidation resistance of the carbon have also been investigated.The results indicated that the HTC have great influence on the microstructure,but little effet can be found on the crystal structure of the carbons,It is found micropore model of the carbon accords with the parallel palne model.The research results also indicated that the oxidtion resistance of the carbons is strongly depended on the factors such as speific surface area,micropore distribution,opening micropore volume etc,the crystal struce-ture has little effect on the oxidation resistance of the carbon.展开更多
Mullite-corundum bricks and kiln furni-ture with high creep resistance and good thermal shock resistance were fabricated based on low cost raw materials,the approaches of introducing some additives and optimisig,chem...Mullite-corundum bricks and kiln furni-ture with high creep resistance and good thermal shock resistance were fabricated based on low cost raw materials,the approaches of introducing some additives and optimisig,chemical composition and partical size were mployed to produce a high temperature matrix phase with high creep resistance and good thermal shock resistance.展开更多
基金Item Sponsored by National Natural Science Foundation of China(59874018)
文摘A mathematical model which describes the fluid flow in a gas stirred original ladle and CAS OB ladle was introduced. The fluid field analysis was obtained through mathematical simulation. In order to decrease the ladle refractory wearing and increase the heating speed of liquid steel, some measures should be adopted. The result shows that the flow fields in CAS OB ladle and original ladle are different. With a fixed gas flow rate, the flow field is related to the plug position and the snorkel depth. When the nozzle is located at 0 45 r , where r is the radius of ladle bottom, the fluid field predicted by water modeling is quite satisfactory for improving the quality of liquid steel.
文摘Phosphate coatings are partially dissolved in the cathodic area during the cathode-electrophoretic painting processes causing the result that the coatings adhesion, corrosion protection, alkaline resistance are decreased. Furthermore, the service life of the coated production will be shortened. The addition of Ni2+, Mn2+ to the phosphating bath to improve the corrosion stability, alkaline resistance, as well as the adhesion of coating layers is studied in the article. These heavy metals do not only catalyse the surface reactions but generate a more corrosion resistant surface. We perfected the trecation phosphate solution by reducing the sludge, accelerating the phosphating reactions, improving corrosion protection and alkaline resistance. More even and finer grain structures, excellent corrosion resistance were obtained compared to the traditional phosphating technique.
文摘The effects of several processing parame-ters on size and distributions of mullite powders were studied in wet grinding with an attrition mill.The results show that there is an optimum initial slurry density,and also it has little rela-tionship with the media charge ratio.The size distributions of processed mullite are dependent on the grinding time and indepentdent of initial pulp density,Under given conditions,the larger the media charge ration is ,the finer the ground particle size will be.
文摘The structure and oxidation behaviors of pitch carbon,resin carbon and their mixture re-sultant carbon have been investigated.The results indicate that the pitch carbon has relative higher true specific gravity,well developed crystalline and better oxidation resistance than resin carbon,With 20%-35% resin added to pitch,the structure of the resultant carbon can be modified and oxidation resistance will be improved significantly.
文摘The structure and oxidation resistance of five kinds of phenol formaldehyde resin-based carbons have been studied.The effects of heating treatment conditions(HTC) of the resins on the crystal structure and microstructure have been investigated,and the relationships between structure and oxidation resistance of the carbon have also been investigated.The results indicated that the HTC have great influence on the microstructure,but little effet can be found on the crystal structure of the carbons,It is found micropore model of the carbon accords with the parallel palne model.The research results also indicated that the oxidtion resistance of the carbons is strongly depended on the factors such as speific surface area,micropore distribution,opening micropore volume etc,the crystal struce-ture has little effect on the oxidation resistance of the carbon.
文摘Mullite-corundum bricks and kiln furni-ture with high creep resistance and good thermal shock resistance were fabricated based on low cost raw materials,the approaches of introducing some additives and optimisig,chemical composition and partical size were mployed to produce a high temperature matrix phase with high creep resistance and good thermal shock resistance.
