The 0.5-2.5 mm cold rolled sheet of test magnetic pure iron is rolled by 350 mm four high reversing finishing mill from 3.5-4.5 mm hot continuous rolled plate of magnetic pure iron (% ： 0.005C

0.50 Al). Results show that the optimum annealing temperature for the magnetic pure iron sheet to get smaller coercive force is 850〜900 °C

the heating and cooling speed of annealing has no obvious influence on the coercive force ； with increasing cold-rolling deformation from 28.6% to 88.9%

the coercive force of pure iron sheet annealed at 900 ℃. increases from 29.8 A/m to 73.5 A/m

therefore the optimum cold rolling deformation to get smaller coercive force is ≤45%.