Abstract: Three ancient Chinese iron coins dating to the first half of the Song Dynasty ( 960-1279AD) unearthed from Shaanxi province are analyzed by time-of-flight neutron diffractionnon-destructively at the ISIS spallation neutron source of the Rutherford Appleton Laboratory, UK. A time-of-flight (TOF) neutron diffractometer GEM was used to measure the phase composition of metal matrix and corrosion products quantitatively, which reveals the iron coins consist of ferrite, cementite, Fe₃P and goethite. No texture was observed from the diffraction patterns of three coins. This work indicates that metal-working technology and deterioration of ancient Chinese iron artifacts can be revealed by TOF neutron diffraction non-destructively and quantitatively, which will be a powerful archaeometrical approach for studying Chinese cultural heritage in future.

Key words: neutron diffraction, Song Dynasty iron coin, time of flight

摘要： 利用飞行时间法中子衍射技术( time of flight neutron diffraction) 对 3 枚陕西出土的宋代铁钱进行了无损的相分析, 采用英国卢瑟福实验室的高分辨率中子衍射仪 GEM( General Materials Diffractometer) , 定量地揭示了铁钱的相组成、合金成分与主要锈蚀产物的成分。分析结果表明铁钱的主要物相为铁素体、渗碳体( 还含有 Fe₃P), 主要锈蚀产物为棕黄色针铁矿(α-FeOOH) , 没有发现铁素体晶粒的织构化, 表明铁钱系铸造而成。中子衍射这种完全无损且量化的物理实验技术在中国文化遗产的科学分析与保护研究中具有广阔的应用前景。

关键词: 中子衍射, 宋代铁钱, 飞行时间法