THE INFLUENCE OF SELECTED ALLOYING ELEMENTS ON THE MICROSTRUCTURE, SELECTED MECHANICAL AND TECHNOLOGICAL PROPERTIES OF BRASSES

The research aimed at assessing the influence of alloying elements, such as aluminium, silicon, nickel as well as lead and bismuth on the chosen alloys of Cu-Zn. Microstructures were examined with the help of optical and scanning microscopy with X-ray microanalysis. The properties of the received alloys were determined with regard to changes in the chosen mechanical parameters, namely  R m , A 5 , HB, also, machinability changes were assessed as well as proclivity to hot  fracturing  of Cu-Zn alloys with additives of lead and bismuth. The results indicate the possibility of obtaining, within the alloys analysed, very high mechanical properties: R m up to 700 MPa, hardness within the range of 130 – 180 HB and A 5 from 3 to 30 %. Also, in the case of the researched alloys, the machining and hot fracturing results  look promising.