RESEARCH ON COPPER RECOVERY FROM SLEDGE FROM SUSPENDED COPPER CONCENTRATE REDUCTION PROCESS

The research on the dispersal of slag from the slurry process was carried out in a laboratory resistance furnace. Before declaring, the slag contained 13.62% copper. In the processes of reduction of slag samples with calcium carbide in the form of carbide with activating additives Na2CO3 and CaF2, the content of copper in the slag was reduced to a level of 0.28–0.63% Cu. The polymetallic melt formed after the decoupling of the slag contained 78.55–84.9% Cu, 10.8–16.48% Pb, and 0.08–0.39% Fe

The Study of the Tensile Strength of AlSi21CuNiMg Silumin in the Final Stage of Solidification and the Initial Stage of Cooling

The paper presents the results of tensile strength tests of AlSi21CuNiMg silumin made on a test stand. Silumin was under examination in an unmodified state and after modification with AlCu19P1.4 master alloy in quantity of 0.2% in relation to the mass of the alloy. Using a scanning microscope, the surface fractures obtained from tensile tests were tested. The structure and profiles of fractures were examined using an optical microscope. Modification of the tested silumin resulted in a favorable fragmentation and regular distribution of the crystals of the primary silicon in the alloy structure, which led to an almost twofold increase in the strength of the silumin samples at the final solidification stage from 3.5 to 6.6 MPa. As a result of these changes, the resistance of silumin to hot cracks should increase, which is of great importance when casting hypereutectic silumin in a metal mould that strongly inhibits the shrinkage of the castings

RESEARCH ON INFLUENCE OF MODIFICATION ON STRUCTURE AND MECHANICAL PROPERTIES OF MANGANESE-IRON BRASS CuZn40Mn3Fe

Research on the modification of manganese-iron brass CuZn40Mn3Fe with the use of variable additions of titanium and boron have shown that these additives cause fragmentation (refinement) of the structures (grains and precipitates of phase a) and an increase in the amount of precipitations of phase a in the brass structure. As a result of this modification, growth in the brass impact resistance (from 40 J/cm2 to 46–48 J/cm2) and tensile strength (from 400 MPa to 509 MPa) are achieved

Hard Inclusions in Armature Brass

The influence of the chemical composition of selected armature brasses on the formation of hard inclusions was investigated. In metallographic studies using optical microscopy and scanning electron microscopy with X-ray microanalysis (EDS), it was found that hard inclusions attain sizes ranging from several hundred nanometers to several micrometers. Investigations of samples that were taken from metallurgical pigs of armature brass of various chemical compositions have shown that the contribution of components such as iron and silicon have a decisive influence on the formation of hard inclusions. These components have a dominant share in hard inclusions (60–76 wt.% Fe and 10.6–17.4 wt.% Si). In much smaller quantities there are also elements such as manganese, phosphorus, nickel and chromium. The chemical composition of hard inclusions varies. The number and size of hard inclusions depends on the contribution of iron and silicon brass. In the brass sample with 0.31 wt.% Fe and 0.08 wt.% Si, 1183 inclusions per square millimeters were identified, while in the brass sample with 0.21 wt.% Fe and 0.11 wt.% Si the amount of hard inclusions was reduced to 933 inclusions per square millimeters. In the brass sample with reduced iron content up to 0.08 wt.% and silicon up to 0.006 wt.%, no hard inclusions were identified

RESEARCH INTO OXIDE INCLUSIONS IN SILICON BRONZE CuSi3Zn3MnFe WITH THE USE OF X-RAY MICROANALYSIS

This paper presents the results of X-ray microanalysis oxide inclusions in silicon bronze in terms of selection microadditions deoxidizers-modifying. On the basis of the oxides present in the alloy, it was found that the most appropriate microadditive is zirconium

INFLUENCE OF TIME ON MODIFICATION EFFECT OF SILUMIN AlSi11 WITH STRONTIUM AND BORON

Studies on the effect of time on the modification of AlSi11 silumin with variable strontium micro additives in the form of an AlSr10 master alloy and boron in an AlB4 master alloy were investigated. The results showed that the strontium micro additive resulted in a satisfactory improvement in the a(Al) + b(Si) eutectic and an increase in tensile strength (Rm) and unit elongation (A5); this is also the case two hours after adding the modifier. The simultaneous modification of silumin with AlB4 and AlSr10 causes a strong fragmentation of the alloy grains and significant improvement in Rm and A5 (also two hours after adding the modifiers)