Complex of research and development work aimed at implementation of jewellery palladium based alloys technology has been carried out at JSC Krastsvetmet. A range of palladium alloys jewellery fabrication has been orga...Complex of research and development work aimed at implementation of jewellery palladium based alloys technology has been carried out at JSC Krastsvetmet. A range of palladium alloys jewellery fabrication has been organized. Compositions of a number of jewellery palladium alloys grade 850, 900, 950 and 990 have been proposed, their production and application in jewellery manufacture has been organized. To produce palladium alloys induction melting in inert atmosphere and melt pouring into a copper mould has been used. The ingots heat treatment conditions, as well as semi-finished jewelry plastic deformation parameters have been determined.展开更多
The internal oxidation behavior of Pd-40Ag-1RE (RE = Sm, Eu, Gd, Y) alloy wires has been studied in air at 800 °C 1200°C. The dependence of internal oxidation depth ξ on reaction time t can be expressed as ...The internal oxidation behavior of Pd-40Ag-1RE (RE = Sm, Eu, Gd, Y) alloy wires has been studied in air at 800 °C 1200°C. The dependence of internal oxidation depth ξ on reaction time t can be expressed as ξ = Ktn, the reaction index n = 0.50 approximately 0.75. The higher the oxidation temperature is, the larger the n value is. It means that the internal oxidation of wire sampls at high temperature deviates from parabola rule observed on plate sample. The activation energies of the studied alloys range over 120 approximately 160 kJ/mol. The internal oxidation process is controlled by the bulk diffusion of oxygen.展开更多
This paper has selected the amino-carboxylic complexing agent EDTA and KCl as the competing ligands of palladium and platinum. Their first-and second-derivative spectra with the zero-point method have been simultaneou...This paper has selected the amino-carboxylic complexing agent EDTA and KCl as the competing ligands of palladium and platinum. Their first-and second-derivative spectra with the zero-point method have been simultaneously determined. This method is simple and rapid, and moderate turbidity does not affect the determination.展开更多
文摘Complex of research and development work aimed at implementation of jewellery palladium based alloys technology has been carried out at JSC Krastsvetmet. A range of palladium alloys jewellery fabrication has been organized. Compositions of a number of jewellery palladium alloys grade 850, 900, 950 and 990 have been proposed, their production and application in jewellery manufacture has been organized. To produce palladium alloys induction melting in inert atmosphere and melt pouring into a copper mould has been used. The ingots heat treatment conditions, as well as semi-finished jewelry plastic deformation parameters have been determined.
文摘The internal oxidation behavior of Pd-40Ag-1RE (RE = Sm, Eu, Gd, Y) alloy wires has been studied in air at 800 °C 1200°C. The dependence of internal oxidation depth ξ on reaction time t can be expressed as ξ = Ktn, the reaction index n = 0.50 approximately 0.75. The higher the oxidation temperature is, the larger the n value is. It means that the internal oxidation of wire sampls at high temperature deviates from parabola rule observed on plate sample. The activation energies of the studied alloys range over 120 approximately 160 kJ/mol. The internal oxidation process is controlled by the bulk diffusion of oxygen.
基金This research item is aided financially by the National Funds of Sciences
文摘This paper has selected the amino-carboxylic complexing agent EDTA and KCl as the competing ligands of palladium and platinum. Their first-and second-derivative spectra with the zero-point method have been simultaneously determined. This method is simple and rapid, and moderate turbidity does not affect the determination.
