抄録
The internal friction introduced by the static compression was compared with that introduced by the impact compression in the commercially pure aluminium. Generally speaking, the internal friction was decreased to a constant value with the standing time at room temperature.
For the initial range of the standing time at room temperature, the internal friction introduced by the impact compression was greater than that introduced by the static compression, but in the later half of the standing time the former was decreased swiftly rather than the latter.
The variation with cold-working level of the internal friction introduced by cold-compressin was given by the difference between the observations on the static compressed specimens and on the impact compressed specimens.
The internal friction introduced by compression was first increased with the cold-compression level, up to some small levels, any 15% reduction of area, in agreement with the expected behavior.
In the measurements for the 15% reduced specimen after standing at room temperature for around 100 minutes, the internal friction introduced by impact compression was greater than that by the static compression as much as a few times.
There results were phenomenologically explaind.
