Abstract: An electric immersion heating apparatus is provided which includes a first tubular electrode which holds a semiconductor substance such as glass or borate lithium oxide therein. Immersed in the semiconductor is at least one other second electrode whose polarity differs from the polarity of the first electrode. The electric current passing through the electrodes heats up the semiconductor material whose heat is thermally transferred through the first electrode into a material, such as aluminum, to be melted. The first electrode may constitute a graphitic ungrounded casing. The heated semiconductor or liquid resistor maintains a uniform temperature, and uniformly transmits heat. The apparatus makes practical 100-200 kilowatts per square foot of surface area times 3-4 feet of immersion depth.

Abstract: A method and system for heat treating metallic substances, especially alloys, and the products obtained thereby. The alloy is subjected to solution heat treating in a fluid media, after which it is quenched in a fluid quenching media. This is followed by natural aging, and a two step artificial aging process. The total time for the process is less than that of conventional techniques, and yet the final resulting alloy has superior physical and mechanical properties. Optionally, ultrasonic treatment can be used in one or more of the steps of the method.