Recycling of aluminum alloy scrap obtained from delaminated fibre metal laminates (FMLs) was
studied through high temperature refining in the presence of a salt flux. The aluminum alloy scrap contains
approximately mass fraction w(Cu) = 4.4%, w(Mg) = 1.1% and w(Mn) = 0.6% (2024 aluminum alloy). The
main objective of this research is to obtain a high metal yield, while maintaining its original alloy compositions.
The work focuses on the metal yield and quality of recycled Al alloy under different refining conditions. The
NaCl-KCl salt system was selected as the major components of flux in the Al alloy recycling. Two different flux
compositions were employed at NaCl to KCl mass ratios of 44:56 and 70:30 respectively, based on either the
eutectic composition, or the European preference. Different additives were introduced into the NaCl-KCl system
to study the effect of flux component on recycling result. Although burning and oxidation loss of the alloying
elements during re-melting and refining take place as the drawbacks of conventional refining process, the problems
can be solved to a large extent by using an appropriate salt flux. Experimental results indicate that Mg in the
alloy gets lost when adding cryolite in the NaCl-KCl salt system, though the metal yield can reach as high as
98%. However, by adding w(MgF2) = 5% into the NaCl-KCl salt system (instead of using cryolite) all alloying
elements were well controlled to its original composition with a metal yield of almost 98%.
ZHU Guo-liang1,2 (祝国梁), XIAO Yan-ping1,3 (肖艳萍), YANG Yong-xiang1,3,4 (杨永祥)
. Recycling of Aluminum from Fibre Metal Laminates[J]. Journal of Shanghai Jiaotong University(Science), 2012
, 17(3)
: 263
-267
.
DOI: 10.1007/s12204-012-1265-1
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