Surface studies of a 2400-year old corrosion resistant ancient Indian Iron Artifact

Abstract

Surface morphology and chemical analysis of 2400 year old sickle-blade excavated in early 1940s from the ancient city Hastinapur, Uttar Pradesh, India has been carried out. The discovery of sickle blade is important archaeological evidence that demonstrates the effective role of iron in agricultural operations. Despite being buried over 2300 years, the blade has survived in good condition. Hence it became essential to determine its fabrication technique and corrosion behavior. The study is carried out in order to investigate the corrosion behavior of this ancient Indian iron. Detailed analysis of the characterization results revealed the valuable information about the production technology of the associated culture. The sickle blade is analyzed by using optical microscopy (OM), scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS), and x-ray diffractometer (XRD). Characterization results lead to the fact that the sickle blade shows heterogeneous microstructure consisting of ferrite, widmanstätten and pearlite structures which is typical of ancient Indian wrought iron produced by bloomery process. Relatively high amount of Phosphorous has been observed which may be responsible for the corrosion resistance behavior of sickle blade. The study reveal the valuable information about the technology and the materials used in the development of iron-based artifacts in India during the ancient period.