The present paper is aimed at recycling of coal ash and blast furnace slag to produce mineral wool. Considering the mineralogical constitutions of coal ash and blast furnace slag, the primary quaternary slag compositi...The present paper is aimed at recycling of coal ash and blast furnace slag to produce mineral wool. Considering the mineralogical constitutions of coal ash and blast furnace slag, the primary quaternary slag compositions of CaO-SiO2-MgO-Al2O3 with basicity (mass ratio of CaO to SiO2 ) ranging from 0.5 to 0.9 and alumina ranging from 5% to 20% were investigated through a rotating cylinder method. The experimental results indicated that the viscosities decreased with increasing basicity above the liquidus temperature, and increased with increasing alumina content, and the maximum values were reached and as the alumina content was 20%, followed by the decrease with further increasing alumina content due to its amphoteric behavior. The amphoteric behavior of Al2O3 also performed in the relationship between viscosity and non-bridging oxygen per tetrahedrally-eoordinated atom (NBO/T), and the viscosities decreased with increasing the NBO/T except the slag with a basicity 0.5 and Al2O3 20 % which have a low NBO/T value and a low viscosity than others.展开更多
The effects of minor alloying elements(antimony,boron) on the recrystallization and oxidation of Mn-containing interstitial free(IF) steels were investigated using confocal scanning laser microscope(CSLM) under ...The effects of minor alloying elements(antimony,boron) on the recrystallization and oxidation of Mn-containing interstitial free(IF) steels were investigated using confocal scanning laser microscope(CSLM) under controlled atmosphere of 95% Ar and 5% H2(volume percent) at different temperatures.The results indicated that oxidation and recrystallization were primarily controlled by the grain boundaries,which moved due to release of the stored energy or acted as the fast path diffusion of alloying elements.It was found that the addition of antimony suppressed both surface oxidation and internal oxidation,whereas boron addition accelerated surface oxidation but decreased internal oxidation.The reasons caused were that the alloying elements of antimony or boron were known to segregate on the surfaces or grain boundaries to occupy the surface adsorption sites,which were expected to be less catalytic than bare iron on the transportation of alloying elements.The recrystallization was also retarded through adding minor antimony and boron elements.The oxidation kinetics of formation of grain boundary oxides were studied through calculating the areas along grain boundaries,and it was found that the areas parabolically increased with increasing time.展开更多
基金Item Sponsored by National Natural Science Foundation of China (50874013)National Key Technology Research and Development Programof China (2007BAB15B04)Program for New Century Excellent Talents in University of China(NCET-07-0071, NCET-08-0723)
文摘The present paper is aimed at recycling of coal ash and blast furnace slag to produce mineral wool. Considering the mineralogical constitutions of coal ash and blast furnace slag, the primary quaternary slag compositions of CaO-SiO2-MgO-Al2O3 with basicity (mass ratio of CaO to SiO2 ) ranging from 0.5 to 0.9 and alumina ranging from 5% to 20% were investigated through a rotating cylinder method. The experimental results indicated that the viscosities decreased with increasing basicity above the liquidus temperature, and increased with increasing alumina content, and the maximum values were reached and as the alumina content was 20%, followed by the decrease with further increasing alumina content due to its amphoteric behavior. The amphoteric behavior of Al2O3 also performed in the relationship between viscosity and non-bridging oxygen per tetrahedrally-eoordinated atom (NBO/T), and the viscosities decreased with increasing the NBO/T except the slag with a basicity 0.5 and Al2O3 20 % which have a low NBO/T value and a low viscosity than others.
基金Item Sponsored by National Natural Science Foundation of China(50902003,51172003)National Key Technology Research and Development Program in 12th Five-Year Plan of China(2010BAE00316,2011BAB02B05)
文摘The effects of minor alloying elements(antimony,boron) on the recrystallization and oxidation of Mn-containing interstitial free(IF) steels were investigated using confocal scanning laser microscope(CSLM) under controlled atmosphere of 95% Ar and 5% H2(volume percent) at different temperatures.The results indicated that oxidation and recrystallization were primarily controlled by the grain boundaries,which moved due to release of the stored energy or acted as the fast path diffusion of alloying elements.It was found that the addition of antimony suppressed both surface oxidation and internal oxidation,whereas boron addition accelerated surface oxidation but decreased internal oxidation.The reasons caused were that the alloying elements of antimony or boron were known to segregate on the surfaces or grain boundaries to occupy the surface adsorption sites,which were expected to be less catalytic than bare iron on the transportation of alloying elements.The recrystallization was also retarded through adding minor antimony and boron elements.The oxidation kinetics of formation of grain boundary oxides were studied through calculating the areas along grain boundaries,and it was found that the areas parabolically increased with increasing time.