The effect of metallurgical structure on the chloride-induced corrosion of archaeological wrought iron
Archaeological wrought iron artefacts are subject to damaging corrosion while in the burial environment and when subjected to environmental changes after excavation. The role of water, oxygen, and chloride corrosion accelerators are central to iron corrosion processes. Intrinsic factors such as the amount and distribution of slag in wrought iron may also play a role in corrosion processes. This study examined a range of factors that impact on understanding conservation desalination treatments to mitigate corrosion by removing chlorides. While examining the effect of slag on corrosion rate and chloride content formed the core of this project, cracking morphologies within corrosion product layers and their influence on corrosion rates measured by oxygen consumption produced outcomes of interest for designing the practicalities of treatment procedures. The slag content of the wrought iron objects examined in this study did not correlate with either their corrosion rate or their chloride content. In line with other authors, clustering of chloride around slag inclusions was identified. This confirmed slag does act as a focus for developing corrosion centres, which will offer challenges for chloride removal and
Nordgren, Eric
CC Archaeology ; Q Science (General)
The effect of metallurgical structure on the chloride-induced corrosion of archaeological wrought iron. Archaeological wrought iron artefacts are subject to damaging corrosion while in the burial environment and when subjected to environmental changes after excavation. The role of water, oxygen, and chloride corrosion accelerators are central to iron corrosion processes. Intrinsic factors such as the amount and distribution of slag in wrought iron may also play a role in corrosion processes. This study examined a range of factors that impact on understanding conservation desalination treatments to mitigate corrosion by removing chlorides. While examining the effect of slag on corrosion rate and chloride content formed the core of this project, cracking morphologies within corrosion product layers and their influence on corrosion rates measured by oxygen consumption produced outcomes of interest for designing the practicalities of treatment procedures. The slag content of the wrought iron objects examined in this study did not correlate with either their corrosion rate or their chloride content. In line with other authors, clustering of chloride around slag inclusions was identified. This confirmed slag does act as a focus for developing corrosion centres, which will offer challenges for chloride removal and
effect metallurgical structure induced corrosion archaeological wrought iron archaeological wrought iron_artefact subject damage corrosion burial_environment subject environmental_change excavation role water oxygen corrosion central iron corrosion process intrinsic factor amount distribution slag work iron may_also play_role corrosion process study examine range_factor impact conservation treatment mitigate corrosion remove examine_effect slag corrosion rate content form_core project morphology within corrosion_product layer influence corrosion rate measure oxygen consumption produce outcomes interest design practicality treatment procedure slag content work iron object examine study correlate either corrosion rate content line author cluster around slag inclusion identify confirm slag act focus develop corrosion centre offer challenge removal