METHOD OF CONTROLLING METALLURGICAL STRUCTURE OF CAST ALUMINUM

摘要

A method is disclosed for controlling the metallurgical structure of cast metals containing nonmetallic second phase structures. The method comprises (1) prior to making casting of the metal, determining a mathematical value associated with the rate of temperature change at liquidus recalescence and a value associated with the rate of temperature change at the eutectic arrest of a measured cooling curve for a sample of the metal melt; (2) comparing the determined values obtained with previously gathered values of the same type that have been correlated to known metallurgical structures; and (3) if the determined values are different than previously gathered values for a desired structure, add modifying and/or refining agents to promote a metallurgical structure change in the melt.