PROCESS FOR PREPARING MOLTEN METALS FOR CASTING AT A LOW TO ZERO SUPERHEAT TEMPERATURE

摘要

A process for preparing molten metals for casting at a low to zero superheat temperature involves the steps of placing a heat extracting probe into the melt and at the same time vigorous convection is applied to assure nearly uniform cooling of the melt. Then, the heat extraction probe is rapidly removed when a low or zero superheat temperature is reached. Finally, the rapidly cooled melt is quickly transferred to a mold for casting into parts or a shot sleeve for injection into a die cavity. The process may be carried out so as that small amounts of solid form in part of the melt. In this case, a key aspect of the invention is to carry out the process rapidly in order to maintain the particles in a fine, dispersed state that will not impede flow and will improve the quality of the metal parts produced. Cost of the metal parts produced is lowered due to longer die life and shorter cycle time.

主权项

1. A method for preparing molten metals for casting at low to zero superheat temperatures, said method comprises:
(a) having a melt of a metal or alloy that is initially above the liquidus temperature in a container from which heat extraction is low to zero; (b) placing at least one heat extraction probe into the melt to remove a controlled amount of heat and applying vigorous convection to the melt to assure nearly uniform cooling of the melt to a low superheat temperature; (c) removing the heat extraction probe from the cooled melt when the desired temperature is reached, in order to substantially stop further cooling; and (d) transferring the cooled melt into a secondary container for casting.