Copper and copper alloys are widely used in various applications due to its excellent thermal and electrical conductivity, corrosion resistance, good strength and ease of fabrication. Alloying copper with other elements gives copper alloys different microstructure and properties. In this study, binary Cu-X alloys (X = Si, Zr, Ti and Ag) with alloying element up to 2 wt% were manufactured by arc-melting high-purity elements using vacuum arc melting system, aiming at investigating the influence of the alloying element content on the microstructure and mechanical properties. 

Binary Cu-X ingots with a diameter of approximately 25 mm and thickness of 8 mm were homogenized at 900 ^oC for 6 h, then cold rolled into 1 mm plates. The cold-rolled plates were annealed at temperatures from 200 to 700 ^oC for 0.5 h in a vacuum tube furnace. The changes in microstructure were analyzed through an optical microscope and scanning electron microscope with energy dispersive X-ray spectroscopy. The changes in mechanical properties were evaluated through tensile and Vickers hardness tests. Si, Zr, Ti and Ag elements form solid solution, intermetallic compound, precipitates and solute-rich phase, respectively. The effects of increasing alloying element on microstructure and mechanical properties will be discussed for each binary copper alloy.