Materials science research on histrical changing of materials and techniques of anciet metal wire

本研究旨在揭示日本考古遗址出土的一条古代金丝的材料和制造工艺，并探讨其在日本的历史。日本生产的现代金线是由薄金面的基膜制成的。它与古代的金丝完全不同。日本出土的古代金线是一种条绞式金线。这是“铁丝”的一种，用来指代由金属线制成的饰品。由于这种金丝的成分超过95%的金和4%的银，材料足够柔软，使它变得很细。扫描电子显微镜的观察告诉我们这根导线的细节。首先，制作了厚度约为15μm的金箔。用一种剪刀或剪刀从铝箔上剪下约300μm宽的窄条。将一条细长的带材扭曲成直径约150μm的圆形截面细小的中空管，单个接缝在钢丝周围呈螺旋状运行。中空钢丝容易变形。虽然它最初是以丝线为核心的想法，但有机材料的痕迹完全消失了。发现了由分层金箔制成的特殊金耳环。这项技术被称为“金箔分层技术”。非常有趣的是，薄薄的金箔是日本出土的古代金丝的第一个重要阶段。

This research focuses to reveal the materials and the manufacture technology of an ancient gold wire excavated in an archaeological site in Japan, and also treats its history in Japan. Japan produces modern gold thread, which is made of the base film with thin gold surface. It is totally different from ancient gold wire. Ancient gold thread excavated in Japan was a strip-twisting wire type. This is the one of"filigrees", which is used injewelry to designate ornaments made from metal wires. Since the compositions of this gold wire were over 95 % gold and 4% silver, the material was soft enough to make it thin. The SEM observation tells us the details of this wire. Firstly, a gold foil, about 15μm in thickness, was made. Narrow strips, about 300μm in the width, were cut out from the foil with a kind of shears or scissors. Finely, a strip was twisted into a fine hollow tube with a round cross-section, which had a diameter of about 150μm. A single seam runs in a helix around the wire. The hollow wire shows deformation easily. Although it is an idea that it originally had silk threads as a core inside, the traces of organic materials were totally disappeared. The special gold earring made by layered gold foils was discovered. This technique was named "gold foil layering technique". It is very interesting thin gold foil was the first important stage of ancient gold wire excavated in Japan.