CONSERVATION TREATMENT OF INLAID OBJECT BY PLASMA

在日本古墓中发现的许多镶嵌文物上都有像两把著名的国宝剑这样的铭文。因此，它们为研究历史提供了丰富的数据。近年来，大量的铭文陆续出土，其中大部分铭文都经过除锈、除垢等处理，获得了较好的学术研究成果。传统的除锈方法存在着使字体笔画变形，从而丢失工艺数据的风险。采用氢等离子体去除嵌体表面的锈层是一种有效的方法，避免了这一风险。通过对嵌体表面锈层的X射线衍射分析，发现氢等离子体和氧等离子体的除锈效果优于氧等离子体。通过观察锈样的变化，找出最佳处理条件。结果如下：H ...更多信息 高频率：13.56MHz，高频输出：2KW温度：约200 ℃气体注入量：氮气：400 ml/min，氢气：400 ml/min，氩气：200 ml/min还发现了锈层如何变得足够脆而被刮除的机理。氢氧化铁和磁铁矿等三价金属的锈通过与氢等离子体反应而被减少，锈层体积的变化，再加上在减压状态下加热的作用，使锈层变得易碎。用等离子体处理锈层后，通过用竹棒仔细地去除易碎的锈层，同时用立体显微镜观察它们，可以揭开镶嵌物。该方法对镶嵌线条无损伤，最适合于出土文物的镶嵌铭文处理。通过一系列的试验，该方法已完全确立为一种实用方法，并已有10多个应用于保护处理的实例。少

Many of the inlaid artifacts found at ancient tomb in Japan have inscription like a two famous national treasure swords. As such, they supply a wealth of data for studying history. In recent years, a lot of objects with inscriptions have been unearthed one after another, and most of their inscriptions have been successfully read by removing rust and other dirt with rewarding great results in academic research. The conventional method of scraping off rust The layrs, however, has a risk of distorting the strokes of charactrs somewhat and there by losing data of manufacturing processes.Using hydrogen plasma to remove rust layrs from the surfaces of inlay is an effective method free from such a risk.Rust examples taken off inlays were analyzed by X-ray diffraction, and it was found that the rust teratment with hydrogen plasma and oxygen plasma, the rust examples were examined to find out the optimum comditions of treatment through observation of their change. The results were as follows :H … More igh frequency : 13.56MHz,High frequency output : 2kWTemperature : About 200ﾟCInjection amounts of gases :Nitrogen : 400ml/min, Hydrogen : 400ml/min, Argon : 200ml/minThe mechanism of how rust layrs become friable enough to be scrapped off has also been found. Rust of trivalent metal such as iron hydroxide and magnetite is reduced through reaction with hydrogen plasma, and a resultant change in the volume of the rust layrs, coupled with the effect due to heating under a state of pressure redaution, contributes to the friable of the rust layrs.After treating the rust layrs with plasma, it became possible to uncover the inlays by carefully removing the friable layrs of rust with a bamboo stick while observing them with a stereomicroscope. This method is free from any harm to inlaid lines and consequently best-suited for processing the inlaid inscriptions of excavated artifacts. The method has come tobe established fully as a practical method through a series of experiments, and there are already more than 10 actual examples of its application for conservation treatment. Less