溶湯直接圧延法によるAl-Cu超塑性合金薄板の製造 Production of Al-Cu superplastic sheets by means of the melt direct rolling
In order to clarify the possibility of simple and novel process to produce superplastic thin sheet, melt direct rolling of Al–Cu alloys was investigated. Sound strips of Al–6%∼20%Cu alloys were successfully produced from molten state by the melt direct rolling process. 47%∼64% of rolling reduction was applied to the materials during melt direct rolling. Fine θ (Al<sub>2</sub>Cu) particles were distributed in the deformed matrix, though the distribution of θ phase was quite inhomogeneous through thickness location in the melt direct-rolled strips: θ (Cu) concentrated near the surface to show inverse segregation. The Al–Cu melt direct-rolled strips were provided for tensile tests at 520°C. Although elongation of the Al–6%–15%Cu melt direct-rolled strips was not large and hardly depended on strain rate, elongation of the Al–20%Cu strip largely depended on strain rate and showed the maximum value of 354% at a strain rate of 4.2 × 10<sup>−3</sup>s<sup>−1</sup>. At the strain rates where large elongation appeared, the strain rate sensitivity (<i>m</i>-value) reached up to 0.32. It could be concluded that it is possible to produce the supelplastic sheets of Al–20%Cu directly from molten state by means of the melt direct rolling.
軽金属 49(8), 395-400, 1999-08-30
The Japan Institute of Light Metals