Hanbing Xu

Degassing of Aluminum Alloys Using Ultrasonic Vibration

The research was intended to lead to a better fundamental understanding of the effect of ultrasonic energy on the degassing of liquid metals and to develop practical approaches for the ultrasonic degassing of alloys. The goals of the project described here were to evaluate core principles, establish a quantitative basis for the ultrasonic degassing of aluminum alloy melts, and demonstrate the application of ultrsaonic processing during ingot casting and foundry shape casting.

Accelerated method for testing soldering tendency of core pins

Abstract An accelerated method for testing die soldering has been proposed and tested. High intensity ultrasonic vibration has been applied through a core pin to molten aluminium in order to simulate service conditions under die casting. Such conditions include high pressure and high impingement speed of molten metal on the pin. Soldering tendency of H-13 steel pins with or without commercial coatings was tested using this accelerated method. The experimental results indicate that soldering occurs within a few minutes of testing using this new method, much faster than that using the conventional methods. The coating failure mechanism identified in this new method is identical to that observed in the conventional methods, suggesting that the new method is suitable for testing soldering tendency of core pins under die casting conditions.

Ultrasonic Degassing of Molten Aluminum under Reduced Pressure

Ultrasonic degassing, an environmentally clean and cheap technique, is an efficient way of degassing in a static volume melt. Vacuum degassing has also been tested a beneficial and clean method in producing high quality products. Combination of these two techniques will make degassing more efficient. An experimental device which combines the vacuum degassing and ultrasonic degassing has been built in Oak Ridge National Laboratory recently. Parametric studies have been carried out to investigate the efficacy of the ultrasonic degassing of molten Aluminum alloy under reduced pressure. This article reports the initial experimental results on ultrasonic degassing under reduced pressure.