The return of equilibrium of structure state of supersaturated solid solutions of lead-cadmium-Bismuth-silver alloys has been studied by different techniques: hardness, micro-hardness, microscopy and X-ray diffraction. Two structural states were considered: raw casting alloy and rehomogenized alloy. We studied alloys Pb2%Cd1%Bi and Pb3,2%Cd2%Bi to which we added the following concentrations by weight of silver to elaborate our alloys: 0,07% Ag, 0,15% Ag, 0, 2% Ag and 0,3% Ag. The explored temperatures are: 20°C and 80°C. Overall, the influence of silver resides in a slight increase in hardness. For the alloy Pb2%Cd3%Bi0,07%Ag, the microstructure is characterized by the formation of Ag5Cd8 compound during solidification.

The study of the return to equilibrium state of PbCdBiSn and PbCdBiMg alloys has been studied. Indeed, two structural states were considered: raw casting alloy and rehomogenized alloy. The experimental temperatures are 20°C and 80°C. The latter temperature was selected because it corresponds to the temperature of ripening of battery grids and extreme temperature for operating a battery. We studied the kinetics of Pb2%Cd1%Bi0,5%Sn and Pb2%Cd1%Bi2%Mg. The activation energy of the alloy without tin remains less than the one with tin and approximate to that with Magnesium.

Abstract:The study of the return to equilibrium state of PbCdBiSn and PbCdBiMg alloys has been studied. Indeed, two structural states were considered: raw casting alloy and rehomogenized alloy. The experimental temperatures are 20°C and 80°C. The latter temperature was selected because it corresponds to the temperature of ripening of battery grids and extreme temperature for operating a battery. We studied the kinetics of Pb2%Cd1%Bi0,5%Sn and Pb2%Cd1%Bi2%Mg. The activation energy of the alloy without tin remains less than the one with tin and approximate to that with Magnesium.

The solid-liquid equilibria of the quasi quaternary system H2O Zn(NO3)2,6H2O Cu(NO3)2,3H2O-NH4NO3 were studied at 25°C by using a synthetic method based on conductivity measurements.Three isoplethic sections has been established at 25°C and the stable solid phases which appear are:NH4NO3 (IV), Zn(NO3)2,6H2O, Cu(NO3)2,3H2O and metastable Cu(NO3),2.5H2O.Neither double salts, nor mixed crystals are observed at these temperature and composition range.

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