a casting process in which the cavity in a foundry mold is filled with liquid metal in a vacuum. In this process the metal that is forced into the mold is freed of its gases, resulting in thin-walled, dense, and high-quality castings. Various methods are used in the production of shaped castings by this process: vacuum suction of the metal into a mold that is located above the melt, after which crystallization takes place at atmospheric pressure or increased pressure; vacuum suction of the metal using metallostatic pressure (the mold is placed under the metal); vacuum pressure die casting (on a pressure die-casting machine using evacuated pressure-cast molds), or vacuum-centrifugal casting. Vacuum casting is commonly used in combination with vacuum smelting for the production of shaped castings from special steels and alloys. Depending on the method, the vacuum may be in the range from 40 to 0.3 newtons per sq m (0.3 to 2 × 10^-3 mm of mercury).