The evaporation coefficients alpha(i) of impurity elements Al, Cu, Cr, Co, Fe, Ni, Si in liquid scandium metal of purity 99.9% were measured at 1550 degrees C and 6.7 x 10(-3) Pa. The separating coefficients beta(i) a...The evaporation coefficients alpha(i) of impurity elements Al, Cu, Cr, Co, Fe, Ni, Si in liquid scandium metal of purity 99.9% were measured at 1550 degrees C and 6.7 x 10(-3) Pa. The separating coefficients beta(i) and activity coefficients gamma(i)(o) of these impurity elements were calculated and the separation possibility between these impurity elements and Sc was discussed from thermodynamics. Then the new technology in preparation of high purity scandium metal was proposed and its purification mechanism was discussed.展开更多
A thermodynamic calculation method on metallic thermoreduction during preparation of aluminum rare metal alloys was presented. Taking preparation of aluminum scandium master alloys using aluminum and magnesium thermor...A thermodynamic calculation method on metallic thermoreduction during preparation of aluminum rare metal alloys was presented. Taking preparation of aluminum scandium master alloys using aluminum and magnesium thermoreduction of scandiumchloride as an example, this method was applied and the results were testified by experiment. [展开更多
The new preparation method of scandium bearing master alloys, in which scandium oxide was fluorinated by reaction with NH 4HF 2 and then reduced by aluminum magnesium in fused salt containing alkali and alkaline f...The new preparation method of scandium bearing master alloys, in which scandium oxide was fluorinated by reaction with NH 4HF 2 and then reduced by aluminum magnesium in fused salt containing alkali and alkaline fluoride under atmosphere, was studied. The effect of sorts of metallic reductive and technique conditions such as reducing temperature and time on the recovery of Sc was discussed. When the liquid aluminum magnesium was used as the reductive agent, the all recovery exceeds 80% and the concentration of Sc in master alloy prepared exceeds 1.9%. The best reducing reaction temperature and time are 1100 K and 40 min respectively. The newly produced Sc from reduction combines with Al to produce the stable compound Al 3Sc, so the reduction progress is sustained and the recovery of Sc is increased.展开更多
The active mechanisms of rare earth element erbium ( Er ) in part of aluminum alloys were investigated. Based on the investigation of the effect of the unitary rare earth elements (Er, La, Y, Ce, Nd, Gd, and Sc) and t...The active mechanisms of rare earth element erbium ( Er ) in part of aluminum alloys were investigated. Based on the investigation of the effect of the unitary rare earth elements (Er, La, Y, Ce, Nd, Gd, and Sc) and the transition element zirconium on the aluminum alloys, it is concluded that, with Er alloyed, high purity aluminum and Al Mg alloys are featured with refined grain structure, superior heat stability and even higher hardness or tensile strength with unchanged ductility; but Er is not beneficial to the mechanical property of Al Cu alloy, so is Sc. It may also be concluded, to most of the aluminum alloys, Er can be an effective alloying element, like Sc; and for the lower price of Er, the cost of modifying aluminum alloys by Er will be reduced.展开更多
文摘The evaporation coefficients alpha(i) of impurity elements Al, Cu, Cr, Co, Fe, Ni, Si in liquid scandium metal of purity 99.9% were measured at 1550 degrees C and 6.7 x 10(-3) Pa. The separating coefficients beta(i) and activity coefficients gamma(i)(o) of these impurity elements were calculated and the separation possibility between these impurity elements and Sc was discussed from thermodynamics. Then the new technology in preparation of high purity scandium metal was proposed and its purification mechanism was discussed.
文摘A thermodynamic calculation method on metallic thermoreduction during preparation of aluminum rare metal alloys was presented. Taking preparation of aluminum scandium master alloys using aluminum and magnesium thermoreduction of scandiumchloride as an example, this method was applied and the results were testified by experiment. [
文摘The new preparation method of scandium bearing master alloys, in which scandium oxide was fluorinated by reaction with NH 4HF 2 and then reduced by aluminum magnesium in fused salt containing alkali and alkaline fluoride under atmosphere, was studied. The effect of sorts of metallic reductive and technique conditions such as reducing temperature and time on the recovery of Sc was discussed. When the liquid aluminum magnesium was used as the reductive agent, the all recovery exceeds 80% and the concentration of Sc in master alloy prepared exceeds 1.9%. The best reducing reaction temperature and time are 1100 K and 40 min respectively. The newly produced Sc from reduction combines with Al to produce the stable compound Al 3Sc, so the reduction progress is sustained and the recovery of Sc is increased.
文摘The active mechanisms of rare earth element erbium ( Er ) in part of aluminum alloys were investigated. Based on the investigation of the effect of the unitary rare earth elements (Er, La, Y, Ce, Nd, Gd, and Sc) and the transition element zirconium on the aluminum alloys, it is concluded that, with Er alloyed, high purity aluminum and Al Mg alloys are featured with refined grain structure, superior heat stability and even higher hardness or tensile strength with unchanged ductility; but Er is not beneficial to the mechanical property of Al Cu alloy, so is Sc. It may also be concluded, to most of the aluminum alloys, Er can be an effective alloying element, like Sc; and for the lower price of Er, the cost of modifying aluminum alloys by Er will be reduced.
