Method for preparing high-flatness metal foil suitable for making metal mask

A method for preparing a metal foil suitable for making a metal mask, comprising the following steps:

• S101, forming a raw metal coarse foil, wherein a material of the formed metal coarse foil is one of invar alloy, iron-nickel alloy, iron-nickel-manganese alloy, iron-nickel-cobalt alloy and iron-cobalt-chromium alloy;
• S102, precision rolling:
• rolling the raw metal coarse foil at least once into a metal foil with a required precision thickness and a flat surface, wherein the metal foil manufactured and formed after precision rolling is 5 μm to 5 mm;
• S103, final heat treatment:
• performing, by a heat treatment device, heat treatment at least once on the metal foil experiencing the precision rolling according to a preset temperature and a preset time;
• S104, tension leveling:
• performing tension leveling at least once on the metal foil experiencing the rolling and the heat treatment using a tension leveler;
• and
• S105, obtaining a metal foil after completion of the tension leveling, and forming a rolled metal foil in a continuous forming process.