The emergence of iron production in Iran reflects both cultural development and chronological transitions from the Stone to Iron Ages. Beheshtabad Hill Chaharmahal and Bakhtiari, registered as a national heritage site in 2006, contains archaeological remains dating from the 4th–1st centuries BC and the Ilkhanid period. Excavated iron objects provide valuable historical information but face rapid deterioration due to corrosion. The aim of this study is to identify the nature of corrosion, the microstructural characteristics of the excavated artifacts from this site, and the necessary measures for their conservation and maintenance in accordance with the condition of the objects. The research methodology includes microscopic observations, (SEM), (XRD), radiography, and metallographic analysis. The results indicate that the artifacts are made of iron-based alloys with a heterogeneous structure, most likely low-carbon iron with carburized zones. Irregular lamellar ferrite and acicular microstructures were observed, which may result from secondary alteration, localized carbon enrichment, or pseudo-phase corrosion products; additionally, in some areas, a pseudo-Widmanstätten structure was identified. XRD identified goethite, reflecting an alkaline, oxygen-rich burial environment with low humidity, and lepidocrocite, which accelerated corrosion. Sediments contained silica and quartz, with corrosion penetrating deep layers and causing cracking. Conservation and restoration treatments were subsequently applied.
Technical Note:
Original Research |
Subject:
Conservation Science Received: 2024/06/8 | Accepted: 2025/11/27