FIB 加工により製作したダイヤモンド金型を用いた超高圧塑性加工

Abstract

This study is conducted to carry out the compression forming of aluminum films using a diamond mold in atmosphere and vacuum without the use of lubricant, in order to evaluate the transcription quality and metallographic structure of such films formed under the two conditions. In the diamond mold, three-dimensional microcavities are formed on the culets of a pair of diamond anvils, using a focused ion beam (FIB) system. Ultrahigh-pressure can be applied to the culets. A high-pressure plastic forming of an aluminum film was carried out using the fabricated diamond mold. The transcription quality of the aluminum film formed in atmosphere was poor because air remained in the mold. In contrast, when plastic forming was carried out in vacuum, the transcription quality of the aluminum film formed was good, because the amount of air remaining in the diamond mold was minimized. It was also confirmed that the average grain size of the aluminum film, which was 20-30 µm when a conventional diamond die was used, was reduced to 1 µm or less after the high-pressure plastic forming. It is considered that an equivalent strain of 4 or more was generated as a result of applying high-pressure, and that the forming conditions were the same as those under a strong strain.