Preparation method of micro order niobium foil

The invention discloses a preparation method of a micro order niobium foil. According to the method, three rolling process reversible type rolling is performed on a niobium belt by utilizing a Sendzimir twenty-roller cold rolling machine, the obtained niobium foil is cleaned, and subjected to edge splitting and heat treatment after each rolling process reversible type rolling, and finally, the micro order niobium foil is obtained. According to the method, three rolling process rolling is performed on the niobium belt with the width being 100 mm to 120 mm and the thickness being 0.15 mm to 0.2mm by adopting the Sendzimir twenty-roller cold rolling machine. Due to the beneficial effects that the Sendzimir twenty-roller cold rolling machine is large in rolling force and high in rolling precision, by designing a reasonable rolling process, the thickness precision of the micro order niobium foil is greatly guaranteed; meanwhile, through a reasonable annealing process, the structure internal stress of the niobium f