Abstract: This disclosure relates to a method of producing a bubbled metal foam, wherein adjusting the size of the bubbles takes place simultaneously with forming the bubbles by the use of oscillations induced by longitudinal waves within a formation region of the bubbles. In this way, a decrease in bubble size which can be caused in an uncontrolled or chaotic manner after the bubbles are created can be avoided. The oscillations are produced along a free surface of a metal melt to provide surface foaming.

Abstract: The invention relates to a method of producing a bubbled metal foam, wherein adjusting the size of the bubbles takes place simultaneously with forming the bubbles by means of oscillations induced by longitudinal waves within the formation region of the bubbles. In this way, a decrease in bubble size which can be effected in an uncontrolled way after said bubbles had been created can be avoided.

Abstract: Various illustrative embodiments of an apparatus and method for reducing the dissolved hydrogen content of a molten metal alloy are provided. The disclosed embodiments can be utilized for the processing of molten metal alloys such as aluminum, and more particularly, for the removal of dissolved hydrogen from molten metal alloys such as aluminum. Gas permeable diffusers can be employed that are wettable by molten metal. When used as gas injectors, either in combination with ultrasonic oscillation or without, the gas permeable wettable diffusers can provide a high density of ultrafine inert gas bubbles that can be used to rapidly and efficiently reduce the level of dissolved hydrogen within the molten metal.