Low pressure die casting, LPDC, is a process in which a ceramic tube is connected to a steel die above and extends into a furnace of molten metal below. The furnace is then pressurized to fill the part by forcing fluid up through the sprue. Once the casting has solidified the air pressure is reduced allowing the rest of the metal still in liquid form in the tube to recede back into the furnace. Low pressure die casting is used for high production rates, thicker parts up to 2.5 mm, for better surface quality, and when high temperature heat treatment is needed to improve strength.