![]() It is known that by pounding of materials rate of chemical processes increases as well as activity of reacting components. Influence of material grain size on its dissolving rate diffusion of the refractory metal atoms into the boundary diffusion layer.Ī number of kinetics researches were performed on dissolution of Fe, Si, Cu, Ti, Co, Cr, V, Mo, W etc. diffusion of the refractory metal atoms in the interrnetallic layer and transfer into melt,ģ. breaking of the atomic bonds in the crystalline lattice of the refractory metal and formation of the interrnetallic compound layer,Ģ. If the limitation stage of process is diffusion through the intermetallic layer.ĭissolution process of refractory metals in aluminum consists of three stages:ġ. Time of alloying element dissolution is short and dependant on melt stirring rate, Driving force thatĭetermines dissolving kinetics is difference between free enthalpy of the element in the crystalline lattice and free enthalpy in the liquid state.įormation of solid intermetallic layer forgoes dissolution of transition metals in aluminum, thus significantly lowering the solubility of these metals in aluminum.ĭiffusion mobility of Al nMe m complex is very small. ![]() Melting point, dissolving is even slower ( Ti, Zr).ĭissolving of metals in melt consists of destroying of their crystalline lattice and transferring of the atoms in the metallic bath. Melting point than aluminum ( Fe, Be etc.) dissolving is slow and it is necessary to additional heat the melt. ![]() If dissolving metal has significantly higher Mg, Zn, Cu and Li dissolve well, without any difficulties in aluminum. Metals are well dissolved in aluminum if they are close to Al in periodic table of elements, isomorphic and not different in atom diameter more chemical properties (electronegativeness).size of component atom diameter change, and,.similarity of crystalline packing of elements in metal-solvent and dissolving metal,.Solubility of elements is dependant from three factors: Kinetics and mechanism of dissolving of metals in molten aluminum Mechanism and kinetics of interactions of pure metal and its compounds with molten aluminum and principles of interaction of molten aluminum with gaseous For understanding of physical and chemical essence of master-alloys production process, it is necessary to research Choice of process for master-alloy production is dependant from several factors: production capacity, demanded quality, Is needed to this issue, which includes analysis of theoretical background and practical ways of alloys and master-alloys production.Įvery deviation from an optimal regime of alloying with refractory metals will cause significant loss in alloying elements while smelting and shortening Master-alloy could be considered as an alloying element and the process and the technology of their production should be carefully controlled.Įven though master-alloys are for very long time used for the production of aluminum alloys there isn't enough data on them. Production of high quality semi-finished products and castings based on aluminum depends on quality of raw materials, especially master-alloys and alloyingĮlements.
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