الفهرس 
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Abstract
In our knowledge no more available research covered the studying of microstructure, hardness and electrochemical corrosion behavior of high copper-based alloys. The aim of our research was to study microstructure, hardness and electrochemical corrosion behavior of high copper based alloys (Cu98X2 where X=Sn or Al or Ni or Mn or Ge). Also to study the effect of annealing at different temperature, 500, 600 and 700 C, for two hours on microstructure, hardness and electrochemical corrosion behavior of high copper based alloys. This research was done because modified copper (high copper based alloys) are used in structural parts and friction materials. To verify these aims: The commercial Cu98X2 where X= Sn or Al or Ni or Mn or Ge alloys were used. Shimadzu x–ray diffractometer (Dx–30, Japan), scanning electron microscope (JEOL JSM-6510LV, Japan) and EDX analysis were used to identify microstructure of used alloys. The digital Vickers micro-hardness tester, (Model-FM-7- Japan), was used to measure Vickers hardness of used alloys. The polarization studies were performed using Gamry Potentiostat/Galvanostat with a Gamry framework system based on ESA300. Gamry applications include software DC105 for corrosion measurements, and Echem Analyst version 5.5 software packages for data fitting. Our work concluded that: Internal lattice microstrain, Vickers hardness and the corrosion rate in 0.25 M HCl of copper increased after adding Ge or Mn or Al or Sn or Ni metal. Crystal size of copper decreased after adding small ratio from alloying elements. Variation occurred in melting temperature, the shape and position of endothermal peak of copper after adding Ge or Mn or Al or Sn or Ni elements. There is a change in matrix structure (peak intensity, began base line and position, 2θ) of Cu98Mn2, Cu98Sn2, Cu98Ge2 alloys after annealed at 500, 600 and 700 C for 2 hours. Lattice microstrain of Cu98Mn2, Cu98Sn2 and Cu98Ge2 alloys varied after annealed at 500, 600 and 700 C for 2 hours. Vickers hardness and corrosion rate of Cu98Mn2, Cu98Sn2 and Cu98Ge2 alloys increased after annealing. Strength (hardness) of copper improved after adding alloying elements and annealing and that is useful for structural parts and friction materials.