Al-5%Mg 合金中の極微量ナトリウムの起源およびその高温延性に及ぼす影響 Sources of a trace amoutn of sodium, and its effect on hot ductility of an Al-5 mass%Mg alloy
This work was performed to clarify the sources of trace sodium which caused a high temperature embrittlement of an Al–5 mass%Mg alloy. Various kinds of Al–5 mass%Mg alloys were prepared by using different raw materials and crucibles. Then, sodium contents of the Al–Mg alloys were analyzed with GD–MS. It was proved that sodium was introduced from the 99.97% purity magnesium. Further, it turned out that sodium was also brought from the 99% purity alumina crucible. Hot ductility of these alloys increased with decrease in the sodium content. From sets of experiments, it is clarified that the high temperature embrittlement of an coarse-grained Al–5 mass%Mg alloy disappears when the sodium content is decreased to 0.01 ppm.
軽金属 48(8), 371-374, 1998-08
The Japan Institute of Light Metals