上海青龙镇唐代铸造作坊遗址出土陶范的分析研究

上海青龙镇相传始建于公元746年,是上海地区最早的对外贸易重镇。2012年青龙镇的考古发掘中发现了 4座熔炉以及熔炉周围堆积的大量陶范、炉渣等,是上海地区首次发现的冶铸作坊遗址,遗址使用的主要年代是唐代晚期。为了解青龙镇唐代铸造作坊遗址出土陶范的制作技术,对遗址出土的陶范进行分析研究,以期揭示唐代青龙镇铸造作坊的制范技术。对陶范型腔面上残留的附着物分析主要元素是铁,表明陶范用于铸造铁器。经分析遗址中出土的陶范由三层组成:面层、背层和稻壳泥层。面层厚约1～2 mm,采用细颗粒泥料制作,致密,在铸造铁器时能确保陶范承受高温液态金属的充型压力,并得到表面光洁的铸件。背层厚约4～7 mm,该层羼入了粗颗粒物,这些羼和料可以减少陶范在干燥收缩和焙烧过程中的收缩变形。稻壳泥层厚约11～16 mm,该层羼入了一定量粗颗粒物,并羼入了大量的稻谷壳,陶范焙烧时谷壳烧失,在陶范上留下了大量的孔隙,便于铸造时型腔中气体的排出。三种不同的材质起到不同的作用,以保证成功铸造出铁器。在冶铸作坊废弃后在其上建造的一口水井内发现的铁釜、铁提梁鼎的形状与遗址中出土陶范所铸器物的形状吻合,应为该遗址所铸造器物。

Study of Tang Dynasty casting moulds from Qinglong Town in Shanghai

Qinglong Town was built in 746 AD and was the earliest foreign trade center in Shanghai. An archaeological excavation at Qinglong Town in 2012 discovered four furnaces, a large number of casting moulds and slag, etc. It was a foundry site and was used for a long time in the Tang Dynasty. From the cross section of a casting mould, there are three layers:cavity surface layer, interlayer and outer layer. Three layers have different effects. The cavity surface layer ensures a smooth casting surface. The interlayer increases the intensity of moulds and reduces the mould shrinkage and deformation in drying. The outer layer includes a lot of rice husk made for the venting of the mould cavity. The moulds indicate that the foundry workers in Qinglong Town used professional mould making technology. The foundry workers could successfully cast ironware.