| dc.description |
The effect of ageing below 200°C on the hysteresis loss in
a-iron containing nitrogen has been investigated. The extent to
which nitrogen is removed from solid solution during ageing, and the
domain boundary hindrance developed, was assessed by mechanical
damping, using a low-frequency inverted torsional pendulum.
Nitrogen, both in solution and as the precipitated form Fe5N, was
found to increase the resistance to domain boundary movement, the
precipitated form being the more effective in this respect. Most
of the damping changes due to ageing are developed in less than 2
hours at 150°C; a further investigation to cover this region would
need to be undertaken to establish quantitative relationships. |
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