Studies on Oxidation Behavior of a Three-Phase Cu-20Ni20Cr-2Si Alloy at 900 ℃ in 0.1MPa Pure O_2

Oxidation behavior of Cu-20Ni-20Cr-2Si alloy was studied at 900 ℃ in 0.1 MPa pure oxygen.Results show that the alloy is composed of three phases.The oxidation kinetics deviates from the parabolic rate law and its instantaneous parabolic rate decreases continuously with time.The present Cu-20Ni-20Cr-2Si alloy is different from the previous Cu-20Ni-20Cr alloy that formed complex scales containing various components and their mixed oxides.On the contrary,it formed a continuous Cr2O3 layer because the adding Si to Cu-20Ni-20Cr alloy decreases the critical concentration of forming reactive component oxides and is able to form the reactive component oxides on the alloy surface easily.