Step Annealing法によるCu-0.3%Cr合金の析出および復元挙動の研究
1973 年 37 巻 10 号 p. 1094-1100
詳細
1973 年 37 巻 10 号 p. 1094-1100
The precipitation and reversion processes of Cu-0.28 wt% Cr alloys were determined from the electrical resistivity change during step annealing of as-quenched and pre-aged samples.
The results obtained are summarized as follows:
(1) The precipitation process is separated into two parts by the reversion process taking place in the intermediate temperature region.
(2) The activation energies of the two precipitation processes were nearly equal and 1.45∼1.42 eV.
(3) The reversion of low temperature precipitates is not complete but partial.
(4) The apparent amount of reversion decreases rapidly as the pre-ageing temperature rises. At a constant pre-ageing temperature, it increases first with ageing time and then decreases after passing through its maximum point.
(5) In the case of high temperature pre-ageing for a short time, such as at 500°C and 600°C for 2 min, the reversion of low temperature precipitates is observed.
(6) The activation energy obtained from the isothermal reversion curves is about 1.83 eV, and its process seems to be described by the first order equation.
