Zone Formation and Precipitation in Cu-Be Alloys during Ageing under Irradiation

抄録

The ageing characteristics of Cu-Be alloys were studied through measurements of the electrical resistance during neutron irradiation with fluxes of 1.5×10¹¹n_f and 2.3×10²n_th/cm²•sec in the temperature range of 100° to 160°C. The resistance of super-saturated specimens incteased rapidly during the initial period, reached a maximum (ρmax), and then decreased slowly. During high temperature irradiation the rate of the resistance change was larger for all specimens and the time to reach the ρmax, was much shorter than during thermal ageing at the same temperature. The reason is that the G. P. zone formation and the precipitation of γ' phases in Cu-Be alloys is accelerated markedly by irradiation. Based on experimental activation energies for the process, the acceleration mechanism is discussed.