In a lubricant composition suitable for use in the manufacture of aluminum
alloys comprising lubricant base selected from the group consisting of
solid lubricants, liquid lubricants, grease lubricants, emulsion
lubricants, and dispersion lubricants, the improvement wherein the
lubricant composition further comprises: an effective amount of water and
surfactant or water and a compound comprising phosphates, borates,
fluorides, and silicates. It is believed that mixing oil with water and
surfactant or one of these compounds provides a method for uniformly
distributing the surface oxide at the meniscus for casting applications,
thereby reducing vertical fold formation that lead to cracks in aluminum
ingots. In addition, the mixture promotes uniform heat transfer around
the mold allowing the solidifying aluminum alloy to stay in contact with
the mold longer and form stronger ingot shells. A process for continuous
or semi-continuous casting of aluminum alloys via the use of this
lubricant composition is also disclosed.