Annealing method of copper-aluminum interface eutectic material

An annealing method of a copper-aluminum interface eutectic material comprises the following steps that (1) a copper-aluminum interface eutectic plate blank formed after cast rolling is put into an annealing furnace, and the annealing furnace is vacuumized and then filled with nitrogen; (2) the plate blank is heated to 250-300 DEG C along with the furnace, heat preservation is conducted for 2-5 h, then furnace cooling is conducted to 50-20 DEG C, and the plate blank is taken out; (3) the plate blank obtained after primary annealing is introduced into a cold rolling mill to be subjected to primary cold rolling, the reduction rate ranges from 40% to 60%, then the rolled composite plate is subjected to secondary annealing, the annealing temperature ranges from 300 DEG C to 350 DEG C, and the annealing time ranges from 1 h to 3 h; and (4) the composite board subjected to secondary annealing is introduced into a cold rolling mill to be subjected to finish rolling for 2-5 times, the reduction rate of each time is 8