Preparation method of ultra-high-purity aluminum alloy material and extrusion cracking device of aluminum melt oxidation film under vacuum condition of ultra-high-purity aluminum alloy material

The invention discloses a preparation method of an ultra-high-purity aluminum alloy material and an extrusion cracking device of an aluminum melt oxidation film under a vacuum condition. The method comprises the following steps: preparing a graphite smelting cylinder, a graphite piston, a steel counterweight and a graphite forming mold; preparing a bottom plate and a panel; preparing a stepped cylinder and the like; assembling and debugging an extrusion cracking device; preparing materials; setting a program; and purifying and smelting the aluminum alloy material. The content of inclusions in the obtained aluminum alloy material is smaller than or equal to 0.1%, the size of the inclusions is smaller than or equal to 10 micrometers, and the detection result shows that the hydrogen content is smaller than or equal to 0.10 cm < 3 >/100 g.Al. The extrusion cracking device adopts a vacuum furnace, comprises a graphite smelting cylinder, a graphite piston, a steel counterweight, a graphite forming die, a bottom pla