Copper-zinc alloys are widely used as contact carrier materials in switching devices for electrical power engineering because of their high electrical conductivity, the higher mechanical strength combined with good formability compared to pure copper (<xr id="tab:Physical_Properties_of_ Selected_Copper_Zinc_Alloys"/><!--(Tab. 5.7)--> and <xr id="tab:Mechanical_Properties_of_Selected_Copper_Zinc_Alloys"/><!--(Tab. 5.8)-->), and at the same time their reasonable economic costs. Especially suitable are the brasses with up to 37 wt% Zn content which are according to the phase diagram all made up from the &alpha; -phase of the CuZn system (<xr id="fig:Phase_diagram_of_copper_zinc_for_the_range_of_0_60_wt_zinc"/><!--(Fig. 5.5)-->). It is important to note the strong dependence of the electrical conductivity and mechanical strength on the zinc content (<xr id="fig:Mechanical_properties_of_brass_ depending_on_the_copper_content_after_cold_working_of_0_and_50"/><!--(Fig. 5.6)-->).