Die-casting technique for manufacturing aluminum alloy step treads in vacuum state

The invention discloses a die-casting technique for manufacturing aluminum alloy step treads in the vacuum state. The die-casting technique comprises the steps of firstly, improving a die, secondly, cleaning the die, thirdly, setting a pouring system, fourthly, setting a vacuum-pumping system, fifthly, selecting aluminum-magnesium alloy materials, sixthly, melting alloy, seventhly, preheating the die, eighthly, conducting pouring and pressure injection, ninthly, opening the die and drawing a core, tenthly, conducting surface treatment and eleventhly, conducting dipping cooling treatment. The die-casting technique is simple in steps and high in practicability. By the adoption of the die-casting technique, the pressure-resisting and skid-proof step treads can be manufactured, and the service life of each step tread is prolonged; and by improving a sprue gate, the pouring uniformity of molten metal is further improved, it is avoided that the molten metal accumulates and cannot smoothly enter a cavity for die cas