Influence of the method of out-of-furnace melt treatment on hydrogen content in 5083 aluminum alloy

Abstract

The work was carried out in laboratory conditions at the semicontinuous ingot casting installation (SICI) in the casting laboratory of the Siberian Federal University. The article presents the results of comparative studies of the dynamics of aluminum saturation with hydrogen over the entire hardware and technological scheme. The article gives a schematic diagram of the semicontinuous ingot-casting unit. Studies were carried out using a single- and two-stage aluminum melt filtration system with the use of ceramic foam filters with an alumosilicate binder bonded with stabilized borosilicate glass. The results of investigations of the ceramic foam filter heating temperature influence (less than 500 oC and higher than 500 oC) on hydrogen concentration in an aluminum alloy are presented. The hydrogen content studies have been carried out during complex passing of aluminum melt through a single- or two-stage filtration by a ceramic foam filter. The paper presents the results obtained by applying a degassing unit that operates on the principle of the molten metal inert gas blowing (argon). During the study, it was found that the average hydrogen concentration in an aluminum alloy before passing through a ceramic foam filter was 0.19 cm3/100 g Al, and that after passing through the filtration system with ceramic foam filters was 0.185 cm3/100 g Al. The paper shows that the ceramic foam filter heating degree does not affect the aluminum alloy saturation with hydrogen. In the course of the work, it was found that the most significant effect of reducing hydrogen concentration could be achieved by blowing aluminum with inert gas (argon) along with filtration by a ceramic foam filter (CFF), which was confirmed by a series of experiments. The research was carried out in the context a regional competition for the best projects of interdisciplinary fundamental scientific research conducted by the RFBR, the Government of the Krasnoyarsk Territory, the Regional Foundation and enterprises operating in the Krasnoyarsk Territory, as well as organizations participating in the Yenisey Siberia complex investment project (No. 20-48-242916).