The tested magnetic pure iron (/% ： 0. 002 - 0. 004C

0. 01-0.02Si

0. 04 - 0. 05Mn

0. 005S

0. 006 - 0. 009P

0. 41 - 1. 16Al) is melted by 200 kg vacuum induction furnace

hot-rolled to 6. 0 mm plate and cold- rolled to 3. 0 mm sheet. The effect of aluminium content (0. 41% - 1. 16% Al) and magnetic-performance annealing temperature (900 -1 050 ℃) on coercive force of cold-rolled sheet has been studied. Results show that with increasing aluminium content the grain size of pure iron increases and its coercive force decreases; properly increasing aluminium content in pure iron is available to increase grain size of annealed sheet and decrease coercive force of sheet; as the aluminium content is up to 1. 16%

by annealed at 1 050 ℃ the coercive force of pure iron may decrease to 16 A/m.